نشریه مدل سازی و مدیریت آب و خاک
سال سوم شماره 3 (پاییز 1402)

Hydrological regimes play a major role in changing the structure and function of ecological processes and river ecosystems. Significant changes in the hydrological regimes of river flow cause the spatial and temporal heterogeneity of river systems and the degradation of natural ecosystem services and threaten biodiversity. Trend analysis and change point detection are important topics in the analysis of hydrological time series. The study area in this research includes the upstream part of the Hablehroud river basin draining to the Bonekoh hydrometry station, located within the jurisdiction of the Tehran province. The Habaleroud river as the main drain of this watershed has recently encountered the pressures induced by human interventions and climate change, resulting in significant changes in its hydrological status.

In this research, using the sequential Mann-Kendall, Pettitt, Buishand Range, Buishand U, Standard Normal Homogeneity, and double mass curve tests, the significant change point in the annual discharge time series (1980–2017) of the Bonekoh hydrometry station at the outlet of the Hableroud watershed was detected. Then, using the Indicators of Hydrologic Alteration (IHA), the alterations in the hydrological condition in the period after the change point (Altered flow regime) compared to the period before the change point (the natural flow regime) were analyzed using the daily observed discharge data of the Hableroud watershed.

According to the research results, in the mid-1990s, a statistically significant change point in the annual discharge time series of the Bonekoh hydrometry station occurred, and most of the hydrological indicators show a deterioration in the condition of the Habaleroud watershed flow regime. Whereas for most of the hydrological indicators, after the change point, the frequency of the low values category has increased and the frequencies of the middle and high values categories, have decreased. These reductions have not only occurred for high extreme values, but also for low extreme values. In addition, the mean monthly discharge for all months of the year and the base flow of the basin have decreased. Both the frequency and duration of low-flow pulses have increased. On the contrary, both the frequency and duration of the high-flow pulses have decreased. For this reason, the frequency and magnitude of high extreme events such as medium and large floods have decreased. The long-term trend analysis indicated that 25 out of the 33 IHA have experienced a statistically significant decreasing trend. Therefore, the mean annual discharge of the watershed at the Bonekoh station has declined from 8.43 m3/s during the pre-impact period to 5.43 m3/s during the post-impact period, which is equivalent to about 35 % decline in the watershed outflow. While the watershed’s mean annual precipitation shows a negligible long-term increasing trend. Therefore, it seems that human interventions across the watershed play a major role in the hydrologic regime alteration of the watershed.

In the Benkoh hydrometric station in the mid-1990s, the hydrological regime of the basin has changed significantly. Then, using special software, the hydrological change indicators and key environmental flow indicators were analyzed in the periods before and after the change point. Unfortunately, most of the hydrological indicators show a downward trend in the Habaleroud river flow. So that the average discharge has decreased in all months of the year. Base current values are reduced. Both the frequency and duration of minimum current pulses are increased. On the contrary, both the frequency and duration of maximum current pulses are reduced. For this reason, the frequency and magnitude of extreme events such as medium and large floods have decreased. The results of the analysis of the trend of several indicators of the environmental flow also indicate the regressive course in the ecohydrological conditions of the Hableroud watershed. So that the minimum monthly flows for all months of the year show a downward trend. On the one hand, the continuity and frequency of periods of water shortage has increased, and on the other hand, the frequency of high flow pulses has decreased. The consequence of these changes will be creating tension and threatening riverside plant and animal communities that live in the flood plains of rivers and provide many ecological services. On the other hand, with the destruction of these riverside communities, the hydraulic conditions of the floodplains have changed and the vulnerability of river ecosystems and infrastructure facilities around the river increases against possible floods and causes a lot of damage. With the continuation of the existing process of managing water resources of the basin, stakeholders and beneficiaries of the basin will face many challenges in the future. Due to the fact that the average annual rainfall of Hableroud basin does not show a decreasing trend, it seems that human interventions are one of the main factors affecting the hydrological changes of this basin. Therefore, it is suggested that the main focus of management policies and measures should be focused on the management and optimization of human interventions in Hableroud watershed. In other words, instead of focusing on the top-down management approach and (hard) structural engineering measures, the focus should be on the participatory management approach and (soft) management engineering measures, and the water and soil resources of this basin should be used optimally and in accordance with the principles of sustainable development, so that at the same time Reducing the conflicts between the beneficiaries and the stakeholders upstream and downstream of the watershed (social challenges and threats) which currently occurred on a larger scale between the two provinces of Tehran and Semnan, and also preventing these conflicts from occurring on a smaller scale between the smaller communities upstream and downstream in The extension of waterways and rivers in the basin prevented the occurrence and spread of diverse environmental challenges and threats and vulnerability to natural hazards such as sudden floods and droughts. Also, it is suggested that the future changes in discharge of the studied watershed should be predicted according to the results of climate change models and land use changes, and suitable solutions should be formulated and implemented in order to deal with or adapt to these changes.

In determining the evapotranspiration (ET) of a crop species, factors such as type, crop density, growth stage, climate of the region, physicochemical characteristics and soil fertility, have a significant effect. Therefore, it has a significant complexity. In recent years, new technologies are used to estimate ET, such as surface energy balance algorithm for land (SEBAL), which estimates actual evapotranspiration, using satellite data and some ground data. The purpose of this research is to estimate the actual ET and water requirement of Rosa damascena using SEBAL during three crop growth years in a part of the Shahrekord high plain.

The studied farm with an area of 16.38 ha is located in the Shahrekord plain, Karoun watershed. The remote sensing data included 42 cloud-free images of Landsat 7 and Landsat 8 satellites (2017, 2018, and 2019). The growth period lasted from the beginning of April to the end of November of each crop year. Images were processed in ERDAS Imagine 2015 software for radiometric correction and subsequent calculations using SEBAL algorithm. In order to estimate the actual evapotranspiration, the energy balance equation is used. For this purpose, all energy fluxes such as, Rn: the net incoming radiation flux to the considered surface, H: the sensible heat flux, G0: the soil heat flux and lET: the latent heat flux of evapotranspiration should be taken into account. The first step in the SEBAL process is to calculate the net radiation flux of the Rn. The second, soil heat flux G0 that is the rate of heat capacity in the soil and vegetation resulting from heat conduction or heat energy used to heat or cools the volume of the soil mass. The third is to calculate sensible heat flux (H) is the rate of heat loss to the air by conduction and convection phenomena, which is caused by the thermal difference. In SEBAL process, two "anchor" pixels are used to create boundary conditions for energy balance. These include as "cold (wet)" and "warm (dry)" pixels that are determined in the study area. A cold pixel is selected at the surface of open water or the surface covered by a well-watered alfalfa crop. It is assumed that the temperature of the surface and the temperature of the air near the surface are the same in this pixel. The "warm" pixel is selected in dry agricultural lands and its ET is considered zero. It is necessary for SEBAL model to establishing a linear equation between the surface temperature (Ts) and the air-surface temperature difference (dT) for each pixel using hot (dry) and cold (wet) pixels.

Based on the results of three years of research in a 16.38 hectare Golmohammadi farm in the Shahrekord plain, using the Sabal algorithm and the number of 42 images on the days of Landsat 7 and Landsat 8 satellites passing, as well as using the modified Penman-Mantith-Fao mathematical relationship. It was found that the amount of evaporation and transpiration of hollyhocks in the studied area was on average 1043.8 mm during the growth period. According to the results of other researchers, which have been conducted using lysimeter data and field studies, it necessarily requires higher costs than remote sensing methods. In this research, the ability of the Sabal algorithm (as one of the best remote sensing algorithms) to estimate evaporation And the actual transpiration and determination of the water requirement of the chrysanthemum plant with a low cost and an easy method compared to the results of other researchers, which were done with difficult and expensive lysimetric methods, were proved and it is suitable to be used for other plant species and in other geographical areas. Results showed that actual evapotranspiration value of rose crop (ETC) obtained from the SEBAL during the three years of experiment were 1089.4, 1021.3, and 1020.6 mm per growth period. In the same period, reference crop evapotranspiration (ET0) values were 1214.8, 1100.5, and 1135.5 mm during the growth period, respectively. In other words, average value for ETC was 1043.8 mm in growth period.

Based on the results of three years of research in a 16.38 hectare Golmohammadi farm in the Shahrekord plain, using the Sabal algorithm and the number of 42 images on the days of Landsat 7 and Landsat 8 satellites passing, as well as using the modified Penman-Mantith-Fao mathematical relationship. It was found that the amount of evaporation and transpiration of hollyhocks in the studied area was on average 1043.8 mm during the growth period. According to the results of other researchers, which have been conducted using lysimeter data and field studies, it necessarily requires higher costs than remote sensing methods. In this research, the ability of the Sabal algorithm (as one of the best remote sensing algorithms) to estimate evaporation And the actual transpiration and determination of the water requirement of the chrysanthemum plant with a low cost and an easy method compared to the results of other researchers, which were done with difficult and expensive lysimetric methods, were proved and it is suitable to be used for other plant species and in other geographical areas.

The importance of heavy rainfall and its consequences have caused this phenomenon to be of special importance in environmental planning and water resources management. Using statistical methods and the discharge data of the Dez river, the heavy floods of this river were extracted to identify the effective factors in their creation. Among all systems leading to heavy rains, the Sudanian system has been the main factor of moisture advection in the lower layer of the troposphere with its expansion to the north and northeast. Due to its thermal characteristics, this system has been prone to receive considerable moisture from the surrounding warm seas. This system has provided the necessary conditions for the creation of surface instabilities in most transitional systems independently and in a smaller number in the integrated state with the Mediterranean system. In the investigation of the middle layer of the troposphere in all the systems that led to the floods of 1993 and 2005, it was observed that the anticyclone cell of Arabia was established over the Arabian and Oman seas and the east of the Arabian Peninsula by moving eastward. In this situation, a very deep trough has formed in the west of Iran, and the southern end of the trough has extended to southern Sudan and northern Ethiopia. The eastward movement of high pressure in Arabia and the significant southward expansion of the Mediterranean trough and the formation of a low-altitude center over Iraq is the most suitable pattern for the heavy cloud rains in the basin.

In terms of geographic location, the Dez basin is limited between 48°10' to 50°21' east longitude and 31°34' to 33°7' north latitude. The studied area is a part of the Dez river basin, which is located almost in the middle part to the end part. After the Karun branch of one of the largest and longest Dez rivers, Dez is formed from two main branches named Caesar and Bakhtiari, and after leaving the mountainous region north of Andimeshk and Dezful, it enters the plain of Khuzestan. For comprehensive and accurate interpretation of pressure systems and assessment of their environmental effects on the earth, the maps of the earth's surface and level of 500 hPa are very efficient. In most cases, the wind direction and temperature distribution at the 500 hPa level are completely affected by the topographic arrangement of the geopotential height at the 500 hPa level. Geopotential height maps are one of the most important and efficient atmospheric maps in synoptic analysis and interpretation. Heavy rains on representative days are analyzed, interpreted, and explained. Two statistical and synoptic methods were used for a more detailed investigation of the synoptic situation of heavy rains in the Dez river basin. In the statistical part, factor analysis, which is one of the widely used statistical methods in climatology, was used, and in the synoptic part, maps of different atmospheric levels were extracted and analyzed using Gardes software for the specified days. To determine the members of each group, the correlation of the scores of each factor with the sea level pressure map in the time period (1964-2020) was calculated, and the members of each group were determined. To determine the representative days, the correlation of the SLP maps of the days of each group was used, and the day that had a high correlation with more days was selected as the representative day. To perform factor analysis, the elements of the database were transferred from the Excel environment to the S-Plus2008 software environment, and then by performing various inferential analysis calculations, the most suitable method was selected to identify the main and effective factors.

As can be seen, the heavy rains of 2013 lasted for 6 days, and the system of 2011 lasted for 7 days. Of course, as mentioned, in some systems, days before or after the end of the activity period of the main system, scattered rains, even with high intensity, have been recorded in some stations. But these scattered rains are considered local rains. The highest peak flow rate of 8556 m3 belongs to the system in February 2013. This system has lasted for 4 days. It took 31 hours to reach the peak of the flood.

In the investigation of the middle layer of the troposphere in all the systems that led to the floods of 1993 and 2005, it was observed that the Arabian anticyclone has been established over the Arabian and Oman seas and the east of the Arabian Peninsula by moving eastward. In this situation, a very deep trough has formed in the west of Iran, and the southern end of the trough has extended to southern Sudan and northern Ethiopia. Therefore, the eastward displacement of the high pressure in Arabia and the significant southward expansion of the Mediterranean trough, and the formation of a low-altitude center cut over Iraq is the most suitable pattern for heavy cloud precipitation in the Dez basin. The peak discharge of floods with a delay of 12 to 24 hours from the day of peak rainfall has created a very intense discharge system. So, the floods of 2005 with a peak discharge of 8556 m3 s-1 and the flood of 1993 with a peak discharge of 4022 m3 s-1, while they were very heavy floods, there were two study periods.

Although the exploitation of mineral resources is very useful for the country, it has a negative impact on human and plant life with its destructive effects. These destructive effects appear as pollution in the soil, which can lead to the imbalance of ecosystems and ultimately endanger human health. In addition, economic development and the expansion of industrial areas, especially coal mining mines, cause heavy metal contamination of the soil to become more severe and cause the destruction of soil resources and the deterioration of ecosystems in different regions of the world. The present study was conducted to investigate the contamination of the two elements Pb and Zn in the surface soil of the Komarzd mining area in Mazandaran province (Iran) due to coal mining.

Komarzd mines in Mazandaran province are one of the largest and oldest coal-producing areas in the central Alborz coal field. Komarzd mines are located 48 km from the southern district of Qaemshahr and 25 km from Alasht. Four indices, including CF, mCF, RI, and Igeo were calculated for 110 samples from surface soil prepared at a depth of 5-15 cm. After separating the rubble, the collected soils were kept in closed plastic bags with a unique code, and a GPS device recorded their location. The samples prepared in a dry environment were transferred to the laboratory. The ICP-MS method at 75 microns was used to analyze and measure the concentration of heavy elements in the collected samples. According to the presence of different elements measured in the region's soil and the compounds in it, two metals Zn and Pb were selected for evaluation and analysis. Sampling was randomly selected based on saved points and drilling tunnels. PCA statistical test is a type of multivariate analysis widely used in sediment, water, and soil pollution studies. Varimax Rotation is one of the most common types of PCA tests to interpret the results and contamination components of the method. This statistical method can be calculated using R and SPSS softwares.

The results showed that the ordinary kriging model is the most suitable model to show the region's concentration distribution of the two metals, PB and Zn. Also, the statistical status of the elements showed that the lowest amount of Zn for the Igeo index is equal to -0.53 and the highest value for the CF index is equal to 0.72. The amount of Pb concentration measured based on Igeo, CF, mCF, and RI indices equals 0.08, 1.03, and 213 mg/kg, respectively (RI<CF<Igeo). The results of the CF and mCF showed that the region has a low or moderate pollution status in terms of the concentration of the two determining elements; in other words, the value of this factor for Zn is less than 1 (CF<1) and the amount for Pb is (3 > CF> 1). The Igeo index showed that Zn with a concentration lower than zero is not polluted, but Pb with a value (0< Igo <1) has a non-polluted to slightly polluted state. The RI also showed that the concentration of the two elements is less than 150 mg/kg, so this index is also in the low-risk category of contamination (RI ≤ 150). By evaluating the graphs obtained from the PCA analysis, it was found that the two elements Zn and Pb in the correlation analysis graph have a good correlation and distribution, and the changes in the two axes show 47.9% and 24%, respectively, for the Igeo. This indicates the presence of environmental factors in the distribution of this element in the environment. The CF also showed that their distribution in region three negatively correlated with environmental factors. Its value for the two axes is 32.5 and 21.9 %, respectively. The correlation of the Zn element is less than -0.5, but the Pb element is more than -0.5. In general, the value of this variable is 8 and 20, respectively, based on the diagram of two minimum and maximum values. The mCF and RI indices showed that environmental factors influence the distribution of the two elements PB and Zn, and among the two elements, the distribution of the Pb element in the mCF and RI, results of 32.8 and 34.4 has the most influence from the distribution of the drilling tunnel and had environmental factors and has a lower correlation than Zn. The effect percentage of these two elements is 32.8 and 23.2%, respectively, and the two elements Zn and Pb have a good correlation and distribution with environmental changes and human factors.

According to the measurements and the results of four indices, the area is uncontaminated or has low contamination in terms of the concentration of two elements, PB and Zn. Therefore, mineral tailings and coal exploitation do not significantly affect the distribution of the mentioned elements. To improve the research results, other indices can be used to determine the role of environmental factors. Also, considering the agricultural lands and water resources of Talar River, it is better to use other elements that directly affect human health and analyze the region's conditions in terms of environmental pollution to achieve better results and accuracy. One of the main disadvantages of measuring the sources of pollution is the many problems in laboratory work and the preparation of laboratory materials. Still, with this research, it is possible to determine the existing doubts in the field of soil pollution for residents and show the impact of mining on the spread of pollutants. A suggestion to improve this research is to consider elements other than Pb and Zn in different environments such as water sources; In general, for a more detailed investigation, other elements that play a role in human health should be investigated.

Drought is considered a complex hazard, whose severity depends on the climate and weather conditions of each region. In fact, drought is caused by dry and unusual weather conditions, among other things, lead to a change in vegetation characteristics. Since this dangerous phenomenon is caused by the lack of rainfall for a long period of time, it slowly and gradually leads to a natural disaster and conquers the environment compared to other environmental hazards. Therefore, it is not noticed and taken less seriously by people and authorities. Undoubtedly, the occurrence of drought and as a result the crisis of reduction and shortage of water resources is one of the main and most important risks of the natural environment that humans have faced since the past. Therefore, it can be stated that the possibility of this natural phenomenon also exists in humid areas. Drought causes unfortunate and in some cases irreparable damage to human life as well as the natural ecosystem which is very different from other natural events such as floods, storms, and earthquakes. So that it has caused wide and big problems in the economic, social, political, and cultural fields. Therefore, the impacts it causes are not only structural and the damage it causes affects different areas. Drought is one of the destructive phenomena of the natural environment that affects a significant number of countries and causes problems. Simultaneous droughts with the period of vegetation growth cause environmental ecosystem consumption, which results in biological compounds such as land surface, soil amount, and plant growth rate, that we need proper management and planning in order to deal with this phenomenon.

In the present study, drought in Marvdasht city was analyzed using remote sensing technology and satellite imagery as a time series. For this purpose, during the statistical period of 20 years (2000-2019), out of 460 satellite imagery of land surface temperature (LST) and vegetation cover (NDVI) were used in conjunction with the MODIS sensor of Terra satellite, from which to estimate the temperature condition index (TCI) and vegetation condition index (VCI) was used. The optimal index indicating the state of drought from satellite imagery, the SPI was also used. In this way, using the rainfall data recorded by synoptic and rain gauge stations in the study area, the SPI was calculated using MATLAB software for the period of 3, 6, and 12 months. One of the other goals pursued in this study is to determine the basic and optimal index, indicating the state of drought in the study area, which is based on TCI and VCI satellite drought indices. Thus, after calculating the SPI and its intervals for each station, the points of each ground station were placed on the maps produced from TCI and VCI satellite indicators. Then, by taking the numerical value of the corresponding points for each of the years of the investigated period, the obtained values were entered into SPSS 22 software and the amount of correlation coefficients between SPI and its intervals with TCI and VCI values was calculated.

According to the drought maps extracted from the TCI, the highest amount of land area with very severe drought in 2016 was 118.90 km2, and then in 2018 with 112.25 km2, and in 2017 with an amount of 101.66 km2 has happened. On the other hand, the least amount of extreme drought area in the first place is related to 2006 with an area of 46.10 km2, and then 2002 with an area of 48.21 km2. In terms of the severe drought category, 2009 with an area of 433.71 km2 experienced the largest area and 2007 with an area of 45.78 km2 experienced the lowest amount of drought. According to the maps obtained from the TCI, a very severe drought situation is observed in the southern and southwestern parts, especially in 2016 and 2018. It is also consistent with the results of the different intervals of the SPI in 2016 and 2018. They are considered as the years in which the highest amount of drought occurred. In addition, the year 2013 has less drought than other years in all three ranges of the SPI. From the comparison of the average SPI values for the studied years with the values obtained from the two indices, TCI and VCI obtained from satellite imagery, the highest amount of correlation coefficient between TCI and six-month SPI was equal to 0.65, which indicates that the TCI satellite index is the optimal index to indicate the drought situation in Marvdasht city.

According to the maps obtained from the NDVI, the studied area has normal and semi-dense vegetation density, which is scattered in all its different areas, so it has more density in the central and northwestern parts. The results of the VCI for the studied area, in none of the years, has not faced very severe drought. In terms of medium aridity, they have experienced the highest amount of drought in 2010 with an area of 62.98 km2 and after that in 2019 with an area of 50.04 km2. In contrast, the lowest drought in this layer was in 2002 with an area of 5.09 km2. According to the maps showing the drought condition of VCI, the studied area has almost the same distribution pattern in all areas and except for a small part of the southern part of the area which has a medium drought condition, the other areas have a mild drought condition and are not dry in most areas.

Choosing an optimal decision-making method for watershed management is a problem that has always attracted the attention of researchers, and various methods have been used to achieve this goal. Participatory management is a collaborative process to participate in gathering information, making decisions, and carrying out projects that lead to solving complex social and environmental problems. As it is known, the integrated watershed management approach is a method to achieve sustainable development. Considering the existence of challenges such as floods, one of the useful approaches to solve the existing challenges is to use the approach of integrated watershed management, which is agreed upon by most of the scientific and executive community. The multidimensionality of the watershed system, its integration with socio-economic systems, and the involvement of stakeholder opinions are one of the most important components in the watershed operation and conservation. Therefore, the present study seeks to investigate the necessity of using inter-sectorial management and benefit from the consensus of the main stakeholders using game theory algorithms in 15 sub-watersheds of the Cheshmeh-Kileh Watershed in Tonekabon City. Sehezar and Dohezar rivers are the most important rivers of the Cheshmeh-Kileh Watershed which originate from the Takht-e-Soliman, Alamut, and Khashchal mountain regions. The high capacity of the riverside lands and the limitation of suitable lands in the watershed have caused many agricultural activities to be concentrated along the river, which is severely affected by floods.

In the present study, semi-structured interviews were used to collect information about the flood generation potential. The stakeholders included local stakeholders, policy makers, and the executive organization. Game theory algorithms including the Condorcet algorithm, Borda scoring, and Fallback bargaining were used to prioritize the sub-watersheds. First, the prioritization of each of the three groups was analyzed, and then the results of the consensus of the group and their comparison with the sectional decisions were examined. In this connection, first, the sample size was determined using Cochran and the opinion of the stakeholders was asked regarding the flood generation potential of the sub-watersheds. The number of interviewees in subgroups of local users, policy making institutions, and executive organizations were 75, 13, and 6 respectively. It is worth mentioning that in order to eliminate the effect of the number of interviewees in the final results; the priorities were standardized and dimensionless. In order to prioritize by the stakeholders, first, various maps of sub-watersheds, roads, and even the location of villages were prepared with appropriate quality. Then, they were asked to prioritize the sub-watersheds in terms of flood generation potential based on their personal experiences, local knowledge, technical and policy. In the group of local watershed users and residents, random sampling was done from 21 Cheshmeh-Kileh Watershed villages in Tanekabon city and Mazandaran province.

Based on the study findings, by comparing the two priorities of the stakeholders and the differences between the popular, institutional and policy-making sectors, it can be said that in the Condorcet algorithm, the rate of differences in the voting of local users with policy-making institutions, local users with the executive organization and policy-making institutions with executive organization is 33.33, 66.67, and 80 %, respectively. These differences based on Borda scoring algorithms and Fallback bargaining are 53.33, 66.67, and 93.33 %, respectively. According to the local operators, in all three algorithms based on game theory, Takht-e-Soleiman, Garmarood, and Selajanbar sub-watersheds have the highest flood generation potential in the Sehezar River. Meanwhile, Ketehroud, Holian, and Yandasht sub-watersheds have a low flood generation potential in this river. Regarding the Dohezar River, it can be said that the results of all three algorithms based on the theory of games were almost the same, and Niardareh, Khashchal, and Nosha have the highest potential, and Miankooh, Daryasar, and Golestan-Mohalleh sub-watersheds have the lowest flood generation potential. The second group of interviewees was the executive organization that used the opinions of technical and watershed management experts of the General Department of Natural Resources and Watershed Management of West Mazandaran-Nowshahr. The opinions of this department were different from those of local users. Also, in the Dohezar River, the Niardareh, Khashchal, and Nosha sub-watersheds were given the highest priority, and the Miankooh, Daryasar, and Golestan-Mahalleh sub-watersheds were the lowest priority.

Due to the fact that in the watershed system and in optimal decision-making, there is a wide variety of opinions and differences of opinion, on this basis, the conceptual basis of the application of multi-objective decision-making methods such as game theory algorithms appears. Therefore, the game theory provides an optimal compromise mode based on different opinions, at the same time, the opinions of different interest groups are considered to an acceptable extent without mixing. This basis clearly confirms the necessity of using participatory management. Because when the number of votes and interest groups increases, it becomes difficult to make a decision, and in this regard, by using multi-objective decision-making methods, a general consensus can be reached to identify the optimal pattern of prioritizing sub-watersheds. The first point is that the amount of differences in voters was the same based on two algorithms, Borda and Fallback, which, of course, the Condorcet algorithm has provided more balanced and acceptable values ​​in terms of comparison. Another point was that in all three algorithms, the amount of differences between the two local user groups and the policy-making body was less, and somehow their opinions were close to each other, and they had high differences with the executive organization. In all three algorithms, the amount of disagreement between the two local user groups and the policy-making institution was less, and in a way, their views were close to each other and had high differences with the executive organization. Also, a different prioritization was observed between the final consensus and the inter-sectorial and inter-institutional views. In general, it can be said that using the opinions of stakeholders in the watershed is fundamental for optimal and efficient decision-making and integrated watershed management, and this framework can be used in various issues in the watershed.

Soil organic matter is one of the main indicators of soil quality and soil production capacity. It provides some nutrients for plant growth and improves the physical conditions of the soil. In addition to the importance of soil organic matter from an agricultural point of view, there is a deep and close relationship between the amount of soil organic matter and the amount of carbon dioxide in the air, global warming, and desertification. In addition, due to the lack of organic matter in the soils of arid and semi-arid regions, the use of organic compounds such as animal manures is considered an important and effective management factor on soil quality and improving the physical, chemical, and fertility properties of the soil. The supply sources of organic fertilizers in Iran are very diverse, which include animal manure, green manure, and all kinds of composts including urban waste composts and sewage sludge. Different sources of organic matter and their effect on plant growth have been investigated by various researchers. One of the effective ways to produce and increase crop yield is the combined use of organic and chemical fertilizers. The use of chemical fertilizers is the fastest and most reliable way to ensure soil fertility. Still, the high costs of these fertilizers, pollution, and destruction of the environment and soil are the defects of these fertilizers. Using organic fertilizers reduces the consumption of chemical fertilizers and increases the production of crops and garden crops. According to the recommendations of the Ministry of Agriculture to use fewer chemical fertilizers and to encourage farmers to use more organic fertilizers, and considering that a major part of the nitrogen in animal manure is wasted before consumption, investigating the effect of organic fertilizers on plant growth is a special priority. Therefore, this research aimed to determine the optimal levels of organic fertilizer and nitrogen for wheat cultivation in the Khorramabad region.

A split plot experiment in a randomized complete block design with three replications was implemented in the agricultural research station of Sarab Chengai Khorramabad during the crop year 2018-2019. This station has a moderate climate, an altitude of 1171 m asl, and an average annual rainfall of 516 mm. This station has a xeric humidity regime and a thermic temperature regime. Experimental treatments were: A- Organic fertilizer as the main treatment: M1 (control), M2 (10 tons of manure ha-1), M3 (20 tons of manure ha-1), M4 (10 tons of compost ha -1), and M5 (20 tons of compost ha -1). B- Consumption of urea fertilizer based on soil test as a sub-treatment: N1 (control), N2 (100% of fertilizer recommended based on soil test), N3 (75% of fertilizer recommended based on soil test), and N4 (50% of fertilizer recommended based on soil test). The type of crops and their rotations were wheat and corn according to common rotation in the region. Chamran variety wheat was planted on 2 November and wheat was harvested on 25 June with the amount of seed used 150 kg ha-1, single grass 704 corn variety was planted on 1 July and corn was harvested on 26 October with the amount of seed used 30 kg ha-1. It was done manually. All operations, such as the method and amount of irrigation water, fighting against pests and weeds, were carried out according to the advice of agricultural experts. This experiment was carried out in the form of alternating wheat and corn.

The results showed that in wheat, the highest straw yield in N3M2 treatment increased by 57.2% compared to control, the highest grain yield in N3M1 treatment increased by 33.6% compared to control, the highest total yield in N3M2 treatment increased by 39.8% compared to control. The highest harvest index related to the N4M4 treatment is an increase of 11.3% compared to the control, the highest number of seeds in the bunch related to the N3M2 treatment is a 50% increase compared to the control, and the highest thousand seed weight is related to the N3M4 treatment, which is a 16.6% increase compared to the control and has no significant difference with N3M3 treatment. In corn, the highest fresh weight of aerial organs related to N3M1 treatment is a 34.3% increase compared to the control, the highest nitrogen concentration of N2M2 is a 16.7% increase compared to the control, the highest seed protein is related to the N2M2 treatment is 15.8% increase compared to the control. Therefore, the use of 75% nitrogen of the soil test for wheat (187.5 kg.ha-1 urea) and 100% of the soil test (200 kg ha-1 urea) for corn, as well as the use of 10 t ha-1 manure have a beneficial effect on the growth characteristics of wheat and corn. In general, for wheat, among the treatments of combined use of organic fertilizer and chemical nitrogen fertilizer, the use of 20 t.ha-1 compost fertilizer along with 50% of recommended urea fertilizer based on the soil test (M5N4 treatment) showed the greatest effect on grain yield. In the case of corn, treatment M4N4 (use of 10 t.ha-1 compost fertilizer along with 50% of recommended urea fertilizer based on soil test) had the greatest effect on fresh weight.

The results of this research showed that in wheat cultivation, the consumption of 75% nitrogen recommended in the soil test can increase yield and yield components compared to control. Combined use of organic fertilizer and nitrogen can significantly increase grain yield, straw, biological yield, the weight of 1000 seeds, harvest index, and the number of seeds in the cluster. The results regarding corn cultivation also showed that the use of 100% nitrogen according to the soil test has a higher efficiency than other treatments. Among the organic fertilizer treatments, 10 t ha-1 animal manure is recommended. Therefore, to reduce the use of chemical fertilizers and increase the quality of soil properties, to prevent the reduction of soil organic matter and the destruction of the environment, the combined use of organic and chemical fertilizers is recommended.

As a result of droughts and human interventions, the Urmia Lake basin has faced increasing unallowable withdrawal of water resources and environmental requirements share. Over the past two decades, a series of natural and human factors have gradually changed the water balance of Lake Urmia. In addition, decreases in precipitation have been the main reason for the gap between water resources and increasing water consumption in the basin, especially in the agricultural sector. In order to deal with the Urmia Lake catastrophe, a working group was formed for the Urmia Lake restoration. The working group planned and proposed solutions to reach the ecological level of the lake in three stages within 10 years through in-basin water supply and inter-basin water transfer programs. The present research, while investigating the solutions for providing the environmental water requirement of Lake Urmia using the Analytic Hierarchy Process (AHP) method, changes in the water volume of Lake Urmia in the scenarios of water transfer from the surface flow of each entering river in the lake in the years of high intensity severe to mild drought, the implementation of the approvals of the national working group to restore Urmia Lake, including a 40% reduction in agricultural consumption from the sources of dams and other rivers without dams, releasing water from dams in non-agricultural seasons, transferring water from urban wastewater and finally transferring water between the Zab basin has quantitatively been evaluated using the MODSIM simulation model. This research will help to predict the amount of transferable water in drought, normal, and drought conditions and to plan the water accounting of the Urmia catchment. 

The watershed of Lake Urmia, located in the northwest of Iran, with an area of 51,876 square kilometers, is one of the six main watersheds of the country, which is located between the provinces of West Azerbaijan, East Azerbaijan, and Kurdistan. In terms of its territorial location, the catchment area of the Zab Kochak river is in the western part of the international border with Iraq and in the catchment area of the Western Border River basin. A significant part of the Zab watershed (source of water transfer) is located outside the country and in Iraq. The route of water transfer between the basins of the Zab basin is from the place of two dams, Silweh and Kaniseeb, which after entering the Godarchai river will eventually enter the Urmia lake water body. The different solutions from the working group’s approval have been selected for developing six scenarios. Then, the Scenarios have been evaluated by the MODSIM model and AHP analysis method. The scenarios are including reducing agricultural expenses from dams in operation, saving by reducing agricultural expenses from other rivers, transferring water between basins, transferring effluent to Lake Urmia, releasing water from dams in operation to Lake Urmia. A hierarchical structure was developed with the aim of evaluating solutions to save Lake Urmia through internal sources and transfer water sources. In this structure, there are four criteria of climate, consumption, economic-social, and environmental status. Sub-criteria of drought, surface water extraction from rivers, extraction from dam sources, extraction from groundwater resources, development of agricultural lands, and ensuring the sustainability of river flow. and providing solutions for inter-basin water transfer, a 40% reduction of agricultural water consumption from surface water sources of rivers and dams, wastewater transfer, and a 40% reduction of agricultural water consumption from underground water sources in Expert Choice software, were analyzed. 

In order to evaluate the effectiveness of the defined scenarios, the simulation model was implemented for future conditions during the next 10 or 15 water years for different scenarios. The results show that the implementation of scenarios 4 and 6, will bring the largest increase in the volume of lake water, of course, with the occurrence of precipitation and proper input. Regarding the results of scenario 1 and the sameness of its results in two periods of 10 and 15 years, it can be stated because in the definition of the scenario, it is a dry year and the amount of evaporation of the lake water is more than the amount of input into the lake. There has been no increase in the lake's water volume for several consecutive years. Also, the results show that in wet and dry years, if the maximum transfer flow scenario is implemented, we will not have a flow from the Zab river to the downstream side, and it will not be accepted from the hydrodiplomacy point of view for the neighboring country in terms of influencing the use of the Dukan dam. Therefore, water diplomacy solutions are needed to reduce environmental threats. Therefore, the issue of transferring water from the Zab basin to Lake Urmia cannot be considered guaranteed in the long term due to the impossibility of reducing the outflow of water from the country to zero. 

In conclusion, in order to evaluate all scenarios to satisfy the environmental needs of Lake Urmia shows that the protection of the lake requires correcting the mistakes of the path traveled in the current and past years, and preferably with a 40% reduction in agricultural consumption from dams and other rivers, groundwater in the basin is the main supplier of Urmia Lake. Inter-basin water transfer is the next priority because the source catchment is able to transfer water in the face of droughts due to the reduction of runoff and related challenges as well as its negative economic and social effects. It will not be as much as predicted and included in the program (600 million cubic meters per year). In addition to that, water diplomacy is necessary in terms of impacting downstream transboundary uses and reducing environmental threats. The results of this research and the high costs of water supply requirements, in parallel with the investigation of controversial options and costs of inter-basin water transfer projects, macro-management of water resources towards demand and consumption management and water saving programs and the modification of water consumption patterns and the legality of the behavior of water users from within the catchment area of Lake Urmia should be low-cost, sustainable and reliable solutions.

In recent decades, the change in most land uses, regardless of the capabilities and limitations of the environment, has led to many problems such as soil degradation and pollution of aquatic ecosystems. Therefore, this study has been conducted to investigate how to reduce the effects of possible future land use changes in the Gorganrood watershed by examining the potential of lands as a solution to protect natural resources. Land management and appropriate use of natural resources in the region and the country in accordance with environmental characteristics are the basic and important principles of sustainable development. One of the basic points in land use planning is to observe the suitability of existing land uses for future utilizations. The meaning of land suitability is to match the characteristics of the land according to the type of use and activities. If the characteristics of the land can meet the needs and requirements of its use, that land will be suitable for its use. Assessing and determining land suitability involves comparing the requirements of each land use type based on the specifications and quality of each land unit. The study of ecological potential determines the appropriate type of land use for a region that can be considered as a base for sound land management. Several studies have been conducted in the field of assessing the ecological potential of the lands using geographical information system and multi-criteria evaluation methods, While, no study has been done to evaluate the ecological potential of future uses, which is an innovation of the present study. Predicting and locating potential areas can provide useful managers and tools for sustainable land management. As a result, the ineffectiveness of the one-dimensional approach and the need for comprehensiveness in adopting the best decisions and management methods, the use of different expertise, and the presentation of different management options and scenarios are necessary to choose the best scenario for land use changes in the future.

The primary step in this study is to investigate how to reduce the effects of possible future land use changes in the Gorganrood watershed by examining the potential of lands as a solution to protect natural resources. Therefore, the Land Change Model (LCM) was used to investigate the possible changes in future land use, and then, using the Geographic Information System (GIS) and multi-criteria evaluation method (weighted linear composition), the most desirable areas for agricultural use, forests and pastures were determined. Land change modeling provides the possibility of analyzing changes to plan and experimentally model future land use changes and land cover. The main stages of land change modeling in order to model and land use changes are as follows: 1) preparation of land use maps; 2) Analysis and identification of changes in land use classes (analysis of changes);3) Modeling the transfer potential of land uses; 4) Predicting land cover changes; 5) Assessment of modeling accuracy (validation); 6) Modeling transmission potential and predicting future changes. Assessing the most suitable areas for future forestry, rangeland, and agricultural uses and preparing a map of the suitability of the area for these three uses using the multi-criteria evaluation method in several stages is described according to the following steps: 1) Goal setting and determining the effective criteria, 2) Standardization of criteria (factor and limitation); 3) Weighting of factors, 4) Integration using linear combination method.

The results showed that during the study period (1990 to 2020), deforestation (279.53 km2), reduction of rangelands (542.598 km2), and agricultural development (413 km2) occurred in the Gorganrood watershed. According to the projected land use plan for 2040, the area of forest, agriculture, and rangeland will reach 1364.98, 2396.09, and 3481.1881 km2 based on the current changes. Meanwhile, based on the ecological potential (Makhdoom model), the area of forest, agriculture, and rangeland will reach 1427.54, 2258.55, and 3567.549 km2. According to the projected land use plan for 2040 under two management scenarios, the area of forest, agriculture, and rangeland in the first scenario (based on the current trend of change) by a change of -5.37, 35.8, and 8.28 km2 to 1364.98, 2396.09, and 3481.18 km2 will be reached. In this regard, reducing the area of forest lands and increasing the area of agricultural lands, rangelands and residential areas indicate that the human factor will play an important role in changing the land use of the Gorganrood watershed. Forest conservation such as afforestation, conservation of irrigated lands as well as rangelands, or limiting agricultural development in sloping lands or creating gardens in upstream rangelands and as a result sustainable watershed management should be adopted. Meanwhile, in the second scenario (based on ecological potential), the area of forest, agriculture, and rangeland changed by 4.27, -100.86, and 96.58 km2 to 1427.54, 2258.55, and 3567.49 km2 will be reached.

According to the results obtained during the study period, there was deforestation, loss of pastures, development of agricultural lands, and development of residential areas in the Gorganrood watershed. The assessment of land cover changes in the Gergunrood watershed showed that during the study period, the most changes were in forest cover and pasture destruction, and the largest increase was related to agricultural use, which was concentrated in the northeastern part of the watershed. The restoration arias with high priority should be determined according to changes in land cover use and in areas where changes in land cover change scenarios are predicted, preventive and protective measures should be taken considering the conditions of land use in the second scenario. Reducing the area of forest lands and increasing the area of agricultural lands, rangelands and residential areas indicate that the human factor will play an important role in changing the use of Gorganrood watershed lands. Preservation of irrigated lands as well as rangelands or limiting agricultural development in sloping lands or creating gardens in upstream rangelands and as a result sustainable watershed management should be adopted.

The effects of weathering and erosion on Quaternary rocks and deposits depend on several factors, some of which are related to the nature of the rock and other factors are related to the external environment. Investigating all of the erosive factors is difficult and complex, therefore, the effective factors should be prioritized and taken into account in order to be able to determine a statistical relationship between the erosive factors and sediment statistics. Investigating the weathering and erodability of rock units is very important because of scientific and experimental knowledge of the rock's erodability in the region and as a result, their ranking and also their resistance to erosive factors can be a great help in evaluating the erodibility of rocks and for decision-making about the erosion control project in the region. For this reason, this study was conducted with the aim of investigating the weathering and rating of the rock mass resistance of geological formations to erosion in the West Islamabad region.

In this research, the role of weathering was investigated with the Lewis Peltier method using isotemperature and isohyetal maps that were produced in the ArcGIS environment using climatic data. Various parameters can be effective in weathering processes, the most important of which are average temperature and annual precipitation, and Peltier models are also created based on these two parameters. For analyzing the resistance of stone units, the inherent characteristics of the parent materials which include mineralogical composition and texture were used. The types of stones and formations in the region were identified using geological maps and Google Earth. In the last stage, the analysis and interpretation of the results and finally the classification of rocks and formations in the study area were done using a qualitative method.

According to the Peltier diagram and the precipitation and temperature of the study area, the results showed that the prevailing regime in the area is moderate chemical weathering. Also, out of the nine morphogenetic states in the Peltier model, two semi-arid and savanna states occur in the climatic conditions of the region. The study area is diverse in terms of rainfall due to its topography condition. The highest rainfall and the lowest temperature belong to the northern part of the region, and the highest annual rainfall is about 700 mm, which is considered one of the Savan regions in terms of morphogenetic regions. The dominant feature of the Savan region can be called the activity of runoff and the moderate influence of the prevailing winds in the region. Other parts of the study area are considered as part of the semi-arid region due to rainfall and average temperature. The most important geomorphodynamic features of these areas are the influence of wind and moderate to intense running water activity. Water erosion occurs due to heavy rainfall in an area. So, if the amount of runoff is high, water and river processes can be intensive, but this situation in the diagram may be somewhat misleading because in areas with high rainfall and high temperature, this type of erosion is weak. Pelletier probably drew this diagram based on the vegetation, precipitation, and temperature condition, because in areas with high temperature and high precipitation, rich vegetation is formed, which prevents soil erosion due to the presence of foliage and an extensive root system. The erodibility of rock and sedimentary units has been divided into six classes considering lithological factors. Each of the sedimentary units that have the highest level of sensitivity and erodibility is classified in the sixth class, that is, very weak, and according to the degree of sensitivity of the units located in the next classes, it decreases with the decrease of the class number, so that the facies located in the first class has the lowest sensitivity. According to the evaluation carried out in the study area, the least erosivity is related to limestone outcrops. Dolomite sensitivity changes from one to four in different areas, and the most sensitivity is related to discontinuous debris deposits, including The types of alluvial sediments of river beds and floodplains, the alluvium and alluvial cones are related to Qt2 and have a level of sensitivity of 6. The comparison of the results of the classification method presented in this research with the amount of observed sediment yield indicated that considering other effective parameters on erosion, it can be trusted with a high and acceptable level of confidence and it can be used to rate the stone units and formations susceptibility to erosion.

As a result of weathering processes, the connected rocks will change to large and small separated materials. These materials rarely remain fixed on the slopes and they move on the slopes due to the gravity and the weight of the mass of materials or under the influence of the transport processes and are transferred to the foot of the mountain in different forms. In the West Islamabad region, due to the heavy rainfalls, mostly moderate chemical weathering occurs. Chemical weathering includes a set of chemical processes and interactions as a result of which substances in the atmosphere such as water, carbon dioxide, and oxygen show a chemical reaction against the minerals in nature, and as a result, new materials and minerals with different characteristics from the primary minerals will be created. Based on field observations and studies, dissolution is one of the most important chemical reactions common in the region. Considering that the dominant regime in the study area is chemical weathering and more than 90% of the area is in the semi-arid area, which is affected by the moderate to the severe activity of running water, as well as the inherent sensitivity of the rocks in the area to erosion, various types of erosion can be seen in the area, which makes it necessary to have suitable soil conservation programs in the region.

Drought can be considered as a dry period that lasts long enough to cause an imbalance in the hydrological situation. In the calculation of drought parameters, four characteristics of drought intensity, duration, frequency and extent are studied. In general, drought is divided into 4 main categories. The most basic type of drought is defined as meteorological drought, which is caused by a lack of precipitation, an increase in air temperature, and evaporation. In the long run, this phenomenon will lead to hydrological drought and lack of surface and underground water resources, and as a result, agricultural drought and decrease in soil moisture and loss of vegetation. Agricultural drought begins when the amount of moisture in the root of the plant decreases to such an extent that it causes wilting and ultimately the reduction of agricultural products. the severity, volume of damages, the boosting trend of drought and its negative economic, social and environmental effects can be predicted and controlled. So, damages can be Minimize the consequences. Also, remote sensing technology has made it possible to evaluate variable surface phenomena namely, drought. In recent decades, due to the nonlinear nature of the phenomena, artificial neural networks have shown the best ability in modeling and forecasting time series in hydrology and water resources engineering. On the other hand, artificial neural networks are able to identify the nonlinear relationship between input and output variables from the data structure. Drought monitoring in Iran, done through methods based on weather stations, is not accurate due to the lack of a scattered network and lack of access to timely data. Remote sensing technology, along with geographic information system, by creating appropriate spatial and temporal capabilities, has made it possible to evaluate and monitor variable surface phenomena such as drought, so that in the last two decades, the use of methods based on satellite data for Drought monitoring has become one of the first priorities of research and specialized organizations. Drought prediction in water resources systems plays an important role in reducing drought damages. In the last few decades, mathematical models have been widely used to predict drought. These models take time series into account and model processes linearly. In recent decades, due to the nonlinear nature of the phenomena, artificial neural networks have shown the most ability in modeling and forecasting time series in hydrology and water resources engineering.

In this research, a standardized precipitation index (SPI) and the normalized difference vegetation index were used to analyze the correlation in the mountainous climate of Iran. Firstly, monthly rainfall data of 88 meteorological stations from 2000 to 2018 were gathered. After performing the necessary statistical tests, the SPI values were calculated in time scales of 1-, 3-, 6-, and 12-month). Then, OLI sensor images of Landsat 8 satellite with a resolution of 30 m were used to extract the NDVI. These images were obtained from USGS on a monthly basis between 2013 and 2018. In total, 72 months were studied in the entire statistical period. After performing radiometric and atmospheric corrections, an average image was prepared every month for NDVI calculation. Then, a multi-layer perceptron (MLP) neural network was used to predict NDVI data for the next month. Last month's NDVI data and one-month SPI were used as input data to predict the next month's NDVI data during the growing season.

According to NDVI, between 2013 and 2018, May is responsible for the highest amount of vegetation density. In addition, SPI-1 shows the amounts of droughts with more intensity and accuracy than other time steps. Hence, in the mountain region of Iran SPI of the dry season takes a larger amount during the first & last months of the year while during summer, especially in October, drought is much more visible. According to SPI, the return period of droughts is 5-6 years. There is a significant correlation between monthly SPI data and NDVI in the growing season. The highest Pearson correlation coefficient between SPI & NDVI is related to SPI with a 1-month time series and the value of this correlation is much higher in April and May. So, the lack of rain in these months will cause a reduction in growing agricultural products in the spring. 

Artificial neural networks are able to identify the nonlinear relationship between input and output. In this type of simulation, even when the set has disturbance and measurement error, the neural network will be able to provide good results. If there is a change in environmental conditions over time, the neural network will be able to provide new results by adjusting new parameters. NDVI has the highest sensitivity to changes in vegetation and is more useful against atmospheric and soil effects, except in cases where there is little vegetation. In conclusion, for predicting vegetation changes during growing seasons in the pastures of the mountainous climate of Iran, using NDVI data and the monthly SPI data is an efficient process. Therefore, it can be concluded that the neural network is a capable model in relation to agricultural drought prediction.

Accurate estimation of reference evapotranspiration (ET0) is essential in water management in the agricultural sector, especially for arid and semi-arid climates. ET0 plays a vital role in the water and energy cycle and is an essential link between ecological and hydrological processes. Therefore, accurately estimating ET0 is a major issue for understanding the water cycle in continuous soil-plant-atmosphere systems. The traditional ET0 estimation methods are mainly based on physical principles, such as Priestley-Taylor, Hargreaves, and Samani, which have many limitations in accurate ET0 estimation in cases of minimum meteorological parameters (such as radiation solar, wind speed, and air temperature). Numerous studies have focused on ET0 estimation using terrestrial data. However, in the case of a lack of meteorological stations, the conventional methods of estimating ET0 using ground data will be inefficient, so remote sensing (RS) provides the possibility to fill such a gap, in such conditions, satellite images are the most effectivefor evaluating ET0 in large areas. Because satellite images have a suitable spatial and temporal resolution, the time series of satellite images can be used to estimate ET0. The successful estimation of ET0 from satellite images paved the way for its prediction using artificial intelligence models. The primary satellite imagery sources can be obtained from Landsat, Moderate Resolution Imaging Spectroradiometer (MODIS), and Global Land Surface Satellite (GLASS). Remote sensing data provides the possibility of recording more information through satellite images. Remote sensing methods can be used to extract vegetation information and different types of radiation, which help estimate ET0.

In the current research, two different agro-climatic locations including Ahvaz and Tabriz stations were selected. According to De Martonne classification method, Ahvaz was classified as dry climate and Tabriz as semi-arid climate. In this research, random forest (RF) and multi-layer perceptron (MLP) algorithms have been used to estimate monthly ET0 in Ahvaz and Tabriz stations. The input parameters were selected from Landsat 8 and MODIS satellite images in the time period of 2014 to 2021. The utilized parameters were the monthly average, Landsat Land Surface Temperature (LSTLand), MODIS Land Surface Temperature (LSTMOD), Landsat Satellite Normalized Difference Vegetation Index (NDVILand) and MODIS Normalized Difference Vegetation Index (NDVIMOD). To evaluate the accuracy of the input parameters and models, the estimated monthly ET0 was evaluated with the monthly ET0 of the FAO-Penman-Monteth equation.

The input parameters for implemented models were Landsat land surface temperature (LSTLand), MODIS land surface temperature (LSTMOD), Landsat Satellite Normalized Difference Vegetation Index (NDVILand), and MODIS Normalized Difference Vegetation Index (NDVIMOD). Six possible scenarios were defined to estimate monthly ET0. The first two scenarios were considered as a single parameter (scenarios 1 and 2) and other scenarios were evaluated with two input parameters. Scenarios 3 and 4 were evaluated based on the parameters of the Landsat satellite and MODIS sensor, respectively. In scenarios 5 and 6, monthly ET0 was estimated with Landsat and MODIS NDVI and Landsat and MODIS LST, respectively, to determine the effect of NDVI and LST values on ET0 estimation. According to the obtained results, for the MLP and RF models in Ahvaz station, the value of R2 ranges from 0.440 to 0.972 and 0.271 to 0.983, respectively. In Ahvaz station, the lowest and highest RMSE is 0.279 mm.month-1 (RF-5 model) and 1.396 mm.month-1 (RF-4 model), respectively. Additionally, in this station, the highest and lowest values of NS are 0.962 (RF-5 model) and 0.042 (RF-4 model), respectively. According to the obtained results, in estimating the monthly ET0, the best performance is related to MLP-6 (R2=0.972, RMSE=0.348, and NS=0.940) and RF-4 (R2=0.983, RMSE=0.279, and NS=0.962). The highest and lowest values of R2 in Tabriz station were 0.988 and 0.186, respectively. Moreover, MLP-4 and RF-5 models in this station have the lowest and highest RMSE, respectively. The results showed that in Tabriz station, the best performances were related to MLP-4 (R2=0.988, RMSE=0.299, and NS=0.935) and RF-4 (R2=0.979, RMSE=0.302, and NS=0.933). In addition, in this station, the RF-5 model has the weakest performance among all models with R2=0.186, RMSE=1.169, and NS=0.012.

The results showed that 1) the accuracy of monthly ET0 estimation in Ahvaz (arid climate) and Tabriz stations (semi-arid climate) with scenario 4 including LSTMOD and NDVIMOD was better than other investigated scenarios; 2) in estimating monthly ET0 using a single input parameter including LSTLand (scenario 1) and LSTMOD (scenario 2), in both Ahvaz and Tabriz stations, scenario 2 had better performance with both MLP and RF models; 3) estimation of monthly ET0 in Ahvaz and Tabriz stations has performed best with RF-4 and MLP-4 models, respectively, with LSTMOD and NDVIMOD input parameters (scenario 4); 4) in the comparison of scenario 5 (NDVILand, NDVIMOD) and scenario 6 (LSTLand, LSTMOD) in both RF and MLP models, scenario 6 has the best performance in estimating monthly ET0; and 5) in the comparison of monthly ET0 estimation in both arid and semi-arid climates, the best performance with a high correlation coefficient was obtained with the MLP model in semi-arid climates.

Crop water productivity (CWP) is defined as the crop yield produced per unit of water consumed, which can be improved by increasing the crop yield with a given water usage or reducing water usage with a given yield. Increasing CWP can thus help to alleviate the water crisis while ensuring food security. Physical productivity alone is not enough to determine the crop pattern and economic productivity should also be considered. Economic water productivity (EWP) expressed as the gross income in USS per unit of water consumed, is relevant for farmers to pursue higher net benefits. Both CWP and EWP terms are important indices for water resource managers to consider when formulating planning policies. The simultaneous consideration of CWP and EWP allows for a more comprehensive and robust exploration when planning the process for developing regional agricultural water-saving measures, such as modifying the regional cropping distribution. This allows farmers to reduce irrigation water use and shift the area of water-intensive crops to ones with efficient water use or higher economic value. Determining crop pattern-based water productivity is especially important in countries with dry climates, whose agriculture depends solely on irrigation and also has low water consumption efficiency. Therefore, instead of consuming scarce water resources, in the production of products that consume a lot of water, it is possible to produce products with lower water consumption and avoid excessive pressure on water resources. Knowledge of crop-water requirements is crucial for water resources management and planning to improve water-use efficiency. Crop water requirements in the growing period depends on the crop growth stage, cropping technique, and irrigation method. About 99 % of the water uptake by plants from soil is lost as evapotranspiration (ET), so, it can be stated that the measurement of actual crop evapotranspiration (ETc) on a daily scale for the whole vegetative cycle is equal to the water requirement of the given crop. Evapotranspiration is defined as the water lost as vapor by an unsaturated vegetative surface and it is the sum of evaporation from soil and transpiration by plants. Knowledge of the exact water loss through actual evapotranspiration is necessary for accurate and effective water management.

For this purpose, in the first stage agricultural condition of the aquifer was investigated through a questionnaire by farmers and experts. To calculate the reference crop evapotranspiration we used the Penman-Monteith equation in this study crop coefficient curves have been prepared according to the agricultural calendar of the Basht aquifer. Net water requirement is calculated from the difference between effective rainfall and evapotranspiration. Water productivity per crop ( ) (kg.m-3) is an important index for determining the agricultural production system efficiency. Water productivity is defined as the proportion of crop yield (kg.ha-1) to irrigation water consumed by crops in the field (m-3.ha-1). Likewise, water economic productivity is measured about or with the economic benefits in a monetary value of outputs over the number of necessary inputs such as water depleted. To calculate the value of each cubic meter of water, the production costs (minus the water) need to be deducted from the income and the remainder needs to be divided by the volume of water. The calculation results are calculated separately for each product. To determine the suitable pattern crop in Basht aquifer, different cropping patterns were evaluated (eight different scenarios).

Based on the results of the Penman-Monteith method, it can be concluded that the gross water requirement (the amount of net irrigation requirement divided by the irrigation efficiency) in dominant crops of aquifer including rice, alfalfa, citrus, watermelon, corn, wheat, rapeseed, legumes, barley respectively were 20234, 14083, 9291, 9170, 7863, 5630, 5411, 5225, and 4821 m-3 ha, respectively. The amount of effective precipitation that provided a part of the crop’s water requirement through soil moisture (green water) for water crops such as Rice and Corn is close to zero. Autumn crops such as canola, citrus fruits, and cereals use green water. To determine the amount of irrigation per hectare of the current crop pattern of the aquifer, the hydro module of each crop was determined. As it is clear from hydromodule, the average required water flow (l s-1 ha-1) for rice, alfalfa, citrus, watermelon, corn, rapeseed, wheat, beans, and barley, equaled 0.63, 0.44, 0.29, 0.29, 0.24, 0.18, 0.17, 0.16 and 0.15 (l s-1 ha-1) respectively. In total, the amount of water consumed by the agricultural products in the aquifer's Basht is 45 millm3, that approximately equivalent to one m3 m-2 of the aquifer cultivation area and this amount is much more than the aquifer agriculture programmable water. The economic productivity of the aquifer’s current cultivation is 45,000 IRR m-3, on average. Also, most aquifer products' physical productivity was less than one. the comparison of different patterns showed that scenarios eight and twohad the highest and lowest amount of water consumption, 45 and 22 millm3, respectively.

The crop pattern will be influenced by parameters such as climatic compatibility of products, water, and soil potentials, needs, interests of agriculture producers, and production income. In the Basht aquifer, the availability of water and the amount of water consumed is one of the most important factors in choosing the cultivation pattern. In the current situation, due to the high temperature and increasing evaporation rate, and the use of seasonal rainfall, crops that spend their growth period in autumn and winter should be included in the cultivation pattern. The simultaneity of water requirements for crops planted together is one of the important parameters in choosing the cultivation pattern. In the Basht aquifer, the water requirement of corn, alfalfa, cucumber, and tomatoes coincide with the citrus water requirement during the time of high water consumption, and the cultivation of one of them may create water limitations for the other crop. In contrast, the cultivation of wheat, barley, and canola have a very small overlap with the citrus irrigation times. Choosing a combination of citrus, wheat, barley, and canola will optimize the cultivation pattern.

Although micronutrients are required by plants in small amounts, they play an important role in plant growth and development. Plant structure, plant enzyme system, formation and degradation of proteins, and production of plant hormones such as gibberellic acid and chlorophyll are affected by micronutrients including iron and zinc. The soil of most regions of Iran has an alkaline pH and is poor in terms of micronutrients, which has occurred as a result of lack of rainfall, a lot of salts such as carbonates and bicarbonates, unfavorable management of irrigation, destruction of vegetation, fallow, indiscriminate plowing, etc. Therefore, organic fertilizers enriched with micronutrients are suitable alternatives due to their high amounts of organic matter content, and their role in improving soil properties. Organic fertilizers have high amounts of macronutrients such as nitrogen and potassium but the amount of their micronutrients is relatively low. Therefore, mixing iron and zinc metals with the organic fertilizer induces the increased available iron and zinc in the organic fertilizer. The increase in the available concentration of iron and zinc can be due to reduction conditions by the organic fertilizer induced. Adding enriched fertilizers with iron and zinc metal scrap to the soil, while eliminating iron and zinc deficiency, reduces the cost of producing chemical fertilizers and their import, and prevents environmental pollution caused by the consumption of these fertilizers and the accumulation of metal scraps. Considering that the effect of fertilizers enriched with metal iron and zinc on the soil has not been studied so far, in this research, the effect of cow manure compost enriched with iron and zinc metal scraps on the concentrations of iron and zinc in soils with different textures was investigated.

In order to investigate the effect of cow manure compost enriched with iron and zinc metal particles on the amount of iron and zinc in soils with different textures, an experiment was carried out in the form of split plots-factorial in a completely randomized block design. The main factor includes soil texture in three types heavy, medium, and light texture. The secondary factors include iron-enriched cow manure compost and zinc-enriched cow manure compost in two levels of zero and 30 t ha-1. At first, the produced cow manure compost was passed through a two mm sieve to remove extra materials (gravel and straw pieces). For enrichment, two percent of iron and zinc scraps were added to 100 gr of dry matter of cow manure compost that was saturated in plastic containers and kept for 60 days under laboratory and moisture conditions. After the enrichment process, the cow manure compost with iron and zinc metal scraps of two percent was added to the soils with field moisture capacity in plastic containers after 60 days. Then, the soils were sampled and the available iron and zinc concentrations of the soils were measured.

The results showed that the use of iron-enriched cow manure compost led to an increase of available iron in different soil textures so that it reached 24.16 mg kg-1 in the heavy soil texture, which was 3.8 times greater than the control treatment in the same texture. Also, the addition of zinc-enriched cow manure compost could increase available iron up to 21.51 mg kg-1. Since this treatment contains highly soluble zinc, the soluble zinc can be placed on the surface of the soil colloids and thus increase the available iron. Cow manure compost treatment enriched with zinc also caused a 3499 % increase in available zinc in the heavy soil texture compared to the control treatment in the same soil texture. The reason for this increase in available iron and zinc can be related to the formation of chelate and complex with soil organic matter components. The interaction effect of cow manure compost enriched with iron and zinc caused a significant increase of available zinc in the soil compared to the application of these fertilizers alone, and the concentration of available zinc in the heavy soil texture reached 70.87 mg kg-1. This can be attributed to the high amount of zinc in zinc-enriched fertilizer (4538.7 mg kg-1) and the synergistic effect of iron-enriched fertilizer, which had a double effect on the chelation of zinc elements with organic matter in the soil.

Based on the results of this experiment, the application of 30 tons per hectare of cow manure compost enriched with iron and zinc metal scraps increased the amount of available iron and zinc in the soil, especially in the heavy soil texture. This issue is probably due to the higher content of organic substances and as a result of increasing their chelation rate with soil organic components. Therefore, it is recommended to use organic fertilizers enriched with iron and zinc along with metal scraps to solve the deficiency of these elements and improve the chemical properties of the soil according to environmental and economic considerations. Also, due to the addition of significant amounts of available iron and zinc to the soil by enriched cow manure compost, it is recommended to consume fewer amounts of enriched manure.

Flood has been one of the natural disasters in the world in the past decades, which has had many economic, social and environmental consequences. In recent years, the increase in population and the lack of attention to the capacities of the environment and the improper use of resources have caused the spread of damages, and this problem reveals the necessity of applying efficient management for mitigating flood damages. Therefore, flood zoning, which includes determining the range of flood progress and its height, and also the characteristics of floods in different return periods, is very important. Since Ferdowsi University of Mashhad is one of the largest and most important scientific centers in the country and is located at the bottom of several large urban basins, this research was conducted with the aim of assessing the flood risk in the campus of Ferdowsi University of Mashhad.

In this study, in order to investigate the characteristics of floods entering the campus of the university, the inlets flows to the campus of Ferdowsi University of Mashhad, which include the 4 main inlet branches of Ab_o Bargh, Pazhuhesh, Loizan and Chahar Cheshme were investigated. Due to the urban development, conversion of natural lands into residential surfaces and encroachment of watercourses in the studied area, disturbance of the natural channels and the reduction of their capacity has been occurred which has been effective in the hydrologic and hydraulic behavior of these areas. For this purpose, the map obtained from Mashhad District 9 municipality was reviewed and revised with the help of field observations, slope direction, topography of the area, the use of Google Earth satellite images and geographic information system (Arc Gis software), and the changes and also the real borders for the related catchment was identified . The inflow data generated based on the amount of precipitation in the upstream area of the Ferdowsi University of Mashhad campus, including discharges with return periods of 25 and 50 years, were collected from Razavi Khorasan Regional Water Company. The input flows to each channel were calculated based on the upstream area of that channel based on the values of the total area of the upstream basin, based on Krieger's second equation.Then, using the HEC-RAS model and the HEC-GeoRAS extension, floods with different return periods were zoned and simulated in the channels inside the campus, and problematic areas were identified.In the present research, in order to collect the required data, it was necessary to have field visits on the study area to make the necessary measurements in addition to data obtained from the relevant organizations. In this regard, to measure the parameters of slope, width and height of water transmission channels as well as the roughness of the channels in the campus of Ferdowsi University of Mashhad, several sections of these channels were observed and evaluated in different branches. for these measurements, different tools such as inclinometer, jalon and geological meter were used.

The results showed that the canals in the studied area have the ability to transfer floods with a return period of two and ten years, but with the increase of the return period, it becomes flooded due to the low height of the bridges in some sections. Based on these results, in the area of the final outlet of the campus and also the Ab_o Bargh canal, , floods with a return period of 25 years and above will cause some problems due to the presence of various obstacles. Also in parts of the Pazhuhesh channel, floods with a return period of 50 years and above would cause damage.Considering the importance and location of the campus of Ferdowsi University of Mashhad and the possibility of damage caused by discharges of more than 10 years floods in this area, in this research various scenarios were proposed for the exit section of the campus to increase the capacity of the channel for floods with different return periods. These 5 scenarios which have been proposed and tested in this research are as follows:• First scenario: removing the protection bars of the bridge opening. The second scenario: reopening one of the blocked openings of the bridge on the exit section.Third scenario: reopening one of the openings together with removing protective bars. Fourth scenario: repening both blocked openings of the bridge on the exit section.  Fifth scenario: reopening both blocked openings together with removing protective bars.According to the results obtained from flood zoning in this research, at the water entrance of Ab_o Bargh, discharges with return periods of 25 years and above, and also in parts of the Pazhuhesh area, discharges with return periods of 50 years and above have the potential to cause damage. Therefore, it is suggested that by constructing a protective wall on the left and right banks of these areas, the transfer capacity of these parts should be increased and adapted for discharges with return period up to 50 years. For this purpose, the considered protective wall in these sections has a height of 1.5 meters and is considered to be 0.5 meters away from the left and right banks. With the construction of these walls, discharge with a return period of 50 years has the ability to pass without causing damage.

Assessment of the results showed Examination of sections and modeling results show that all sections have the ability to pass floods with a return period of up to 10 years.also that it is possible to prevent the risk of flooding in the campus of Ferdowsi University of Mashhad by modifying sections in the outlet of the campus and creating a protective wall in the areas of Ab_o Bargh and Pazhuhesh canals to prevent the risk of flooding until the return period of 50 years. According to the obtained results, the largest area of the flooding in different return periods in campus of the Ferdowsi University of Mashhad is related to the final exit section of the campus.

Flood is one of the most important threats to human society, which has increased in recent decades with the increase in population and climate change. Therefore, studying the features of the basins, which are related to the level of flooding, can help in the correct management of this riskWatersheds are different in morphological characteristics, so they have different hydrological reactions in the same climatic and environmental conditions. The stability of the morphometric characteristics of the sub-basins has made them used in flood studies. So that the investigation of the morphometric factors of the basins can be of great help to the management and prioritization of flood sub-basins.In this research, an attempt has been made to introduce and prioritize flood-prone sub-basin using morphometric data in the environment of the geographic information system in the north of Birjand Plain, using the maximum entropy method and VIKOR decision-making model.

Location of Birjand plain This plain is located in longitude 58 degrees 45 minutes to 59 degrees 30 seconds and latitude 32 degrees 30 seconds to 33 degrees. The area of Birjand Plain watershed is 3155 square kilometers, of which 1045 square kilometers are plains (33%) and the rest are highlands.In this research, morphometric factors (13 factors), entropy method and VIKOR decision making method were used to prioritize 22 watershed sub-basins in the north of Birjand Plain. Since the morphological factors of the aquifer basin have different effects on the processes of runoff formation, there is a need to determine the effects of the parameters, which Shannon's entropy method is used in this research. In the following, using the VIKOR method, sub-areas are prioritized.

Morphometric factors are important in identifying and determining flood risk areas. The effect of morphometric factors on flooding is not the same, so it is necessary to determine the importance of each parameter. Shannon's entropy method was used to determine the impact of different morphometric factors (14 parameters) on flooding in the northern Birjand plain watershed (Table 2, row 2). The results showed that the index of the Vf parameter with a relative importance of 0.51 had the greatest impact on flooding and prioritization, which is consistent with the results of Shirani and Chavoshi (2017), Rahmati et al. (2014) and Amiri et all (2017) does not match, and it is consistent with the results of Beheshti Javid et al. (2017) that different areas are different in terms of flooding and are influenced by morphometric factors and land cover. The indicators of channel maintenance and meandering index of the river had the least impact on the flooding of the sub-basins of the studied area.In prioritizing the flooding of sub-basins, all factors are not the same in terms of influence, so some factors have a positive effect and some have a negative effect on flooding, for example, the more the amount of drainage density increases, the more it has a positive effect and causes an increase in flooding. It is possible that if the parameter of the channel maintenance index is lower, the flooding will be more. This attitude and point of view has not been seen in many studies, but in this research, the nature of the parameters was determined based on the opinions of experts and previous studies. In this study, the increase of basin asymmetry indices, tissue ratio index, channel maintenance index, and valley width to height ratio index have a negative effect, that is, with their increase, there is less flooding, and other factors have a positive effect, that is, with their increase, flooding and runoff production also increases, which is consistent with the research of Esmaili et al (2016).

Watershed projects are one of the most important strategies for flood control. The implementation of watershed projects for flood control requires the determination of flood producing areas and their prioritization. Considering the lack of sufficient hydrometric stations at the level of the sub-basins and the lack of recorded statistics and information about floods in the country's watersheds, it is practically impossible to infer the severity of sub-basin floods from the available data alone. Therefore, it is appropriate to use methods such as morphometric factors that require less hydrometric and quantitative data. There are various methods for determining the amount of runoff and prioritizing sub-basins in terms of flooding, and most of these methods are based on graphical methods and the use of empirical formulas, statistical analysis of flood data, and basin separation. In this research, 14 morphometric parameters were used to prioritize floods in the north of Birjand Plain, because the morphometric characteristics of each watershed sub-basin is like its fingerprint, and it is possible to prioritize sub-basins for flood control based on that. In this research, subareas 9, 22, and 14 were prioritized 1 to 3, respectively, based on morphometric criteria.

Water scarcity due to climate change and a growing water demand in different consumption sectors is a major environmental crisis that drives arable lands to the state of degradation, especially in dry regions. Artificial recharge of groundwater (ARG) through floodwater spreading (FWS) which is a potential measure for reversing this emerging trend is investigated in this research. Floodwater harvesting has become an increasingly important technique to improve water security and caused a renewed interest in research and implementation. According to the diverse objectives and methods of implementing artificial recharge of groundwater (ARG) systems, various factors need to be considered when choosing a method for quantifying recharge. Therefore, the rate of aquifer recharge is one of the most difficult items to measure in groundwater (GW) resources evaluation . In soil water balance method (and in Zero Flux Plane method as well), soil water movement is inferred by measuring the changes in water content of the soil profile by gravimetric sampling or automatic devices. These methods have not been proven satisfactory in low flow conditions, as there is often insufficient resolution to detect movement of small quantities of water. Therefore, other methods, based on hydraulic conductivity, potential gradients and directly calculated water fluxes for unsaturated flow were developed. The Buckingham-Darcy law can be used under the steady flow condition where water contents and fluxes change with depth but do not vary as a function of time . It has been employed in arid and semiarid conditions for recharge estimation . or for assessing the exchange flow between surface water reservoir and GW. The method requires measurements or estimates of the vertical total head gradient and the unsaturated hydraulic conductivity at the ambient soil water content following the Buckingham-Darcy equation . The overall objective of this research is to evaluate a floodwater spreading system that was installed in 1981 at the Gareh Bygone Plain, southern Iran for recharging the groundwater table. To assess artificial recharge of groundwater through turbid floodwater spreading, three wells, ~30 m deep, were dug in a 37-year-old recharge basin in planted Acacia forest, bare soil and pasture land uses, respectively. Soil hydraulic parameters of the vadose zone layers (30 m thickness) were measured in the field and laboratory. One well was equipped with pre-calibrated TDR sensors throughout the well profile for measuring the changes in soil water content along the vadose zone. The volumetric soil-water content was measured continuously from August 2010 to May 2019 with closer temporal increments after floodwater spreading events. Rainfall, ponding water depth, and its duration were also measured. Recharge through the vadose zone was assessed by soil-water balance (SWB) method, as measured in the field as well as by calibrating Hydrus-1D (H1D) model through inverse solution. Results showed that the wetting front was interrupted at a layer with fine soil accumulation over a coarse textured gravely layer at the depth of ~4 m. The large differences in hydraulic conductivity of the two successive layers seemed to cause transformation of the wetting front water movement into fingering flow. The changes in downward water flux complicated TDR measurement after the depth of 4 m. however, noticeable but temporarily changes in the soil water content were detected in some of the layers below the 4 m was evidence for fingering flow after the flood events. Validation of the simulated flow by the H1D model vs the observed by SWB (with RMSE 3.45; R2 0.994) showed that the model performed well in flux estimation and. Recharge ratio was calculated for the 2010 to 2019 events as 26 to 84 average 55% for all events and 63 to 84 average 75% for large impounded floodwater in the basin, respectively. Although a reliable set of data is obtained for calculating recharge at the very location of this study, up-scaling of the results for the entire floodwater systems and for the other flooding events with extreme volumes and flow rate needs extended investigation period and thorough identification of the underlying layers. The determined hydraulic properties of the RLs obtained in this study will be utilized in the future research works in the FWS systems in our study site. The contributions of this thesis can be summarized as: a) development of approaches for application, calibration and validation of existing models with limited available data, b) incorporation of new concepts into the models used, c) generating a unique and robust field data set to support the modelling approaches, and d) provision of new information in the context of floodwater harvesting and its impact on groundwater recharge. Floodwater harvesting, especially in the form of FWS, is an emerging issue in water management in dry regions, which needs better understanding and evaluation of its impact on the surrounding environment. Small scale but nature friendly water management plans, such as FWS systems, are seriously criticized, since there are numerous methods, which are more attractive in terms of investments and money return to investors. However, they are rarely investigated. This study provided quantitative evidences that proves the effectiveness of FWS systems.

Agriculture has played a vital role in the economy, life, and culture in the civil history of Iranians. In recent years, this sector is the largest consumer of freshwater resources in this country. One of the adaptive ways to deal with the water shortage is the optimal use of water (Emami et al, 2020). In the production process of a commodity, different sources of water may be used, and the type of water supply source can play a significant role in the analysis of virtual water trade (Mircholi et al, 2016). In the period of 2016-2018, previous research covered by the Moghan irrigation network has been conducted in the field of physical and economic water productivity indicators estimation of crops. Also, in previous studies, only Benefit Per Drop (BPD) and Net Benefit Per Drop (NBPD) indices have been used to estimate the economic productivity of agricultural water. Therefore, in this research, the agricultural year 2020-2021 was studied in order to investigate the physical and economical water productivity indicators of crops covered by the Moghan irrigation network.

The Moghan plain is located in the northwestern part of Iran, on the west side of the Caspian Sea, and north of Ardabil province, on the border between Iran and the Republic of Azerbaijan. The total area of the Moghan watershed is more than 5545 square kilometers (Sookhtanlou, 2019). The altitude of the region is 50 to 600 meters above sea level and its climate is semi-arid and moderate (Azizizohan et al, 2021). Most of the agricultural farm covered by Moghan's irrigation and drainage network is devoted to cultivating crops such as wheat, barley, seed corn, fodder corn, soybean, rapeseed, rice, tomato, cotton, sugar beet, and peanut. In this research, these products' virtual water content and physical and economic water productivity are investigated.
In this research, in order to complete the previous studies in the aforementioned field, the virtual water content of the studied products has also been investigated. In addition to the BPD and NBPD index, the Unit Virtual Water Value (UWV) index has been studied to further investigate the Moghan irrigation network economic efficiency of water crops.

The content of gray virtual water, blue virtual water, green virtual water, and white virtual water of the studied crops, sugar beet, tomato, and fodder corn, have the lowest content of gray virtual water among crops. Among the studied crops, fodder corn, tomato, and sugar beet products, respectively, have the highest physical water productivity, and rice, soybean, cotton, and peanut respectively have the lowest physical water productivity. The amount of physical water productivity calculated in this research for all the jointly studied crops except tomato, canola, and seed corn is lower than the amount of physical water productivity estimated by Farahza et al (2020).Regarding gross value index per unit of irrigation volume among the studied crops tomatoes, peanuts, fodder corn, barley, and wheat, respectively have the; highest, moreover peanut, tomato, cotton, fodder corn, and sugar beet products, respectively, have the highest net value index per unit of irrigation volume among the studied crops, however, barley, wheat, rice, and grain corn, respectively, have the lowest net value index per unit of irrigation volume among the studied crops. In addition, tomatoes, peanuts, fodder corn, wheat, and barley have the highest index of value per virtual water unit among the studied crops, respectively, while rice has the lowest value index per virtual water unit among the studied crops.According to the BPD index, tomatoes, peanuts, fodder corn, barley, and wheat are the first to fifth priorities for cultivation in the Moghan Plain. The first to fifth priorities for cultivation in the Moghan plain according to the NBPD index are peanuts, tomatoes, cotton, fodder corn, and sugar beet, and based on the UWV index, tomatoes, peanuts, fodder corn, wheat, and barley are the first to fifth priorities.

In the current research, the content of virtual water and the amount of physical and economic water productivity of crops covered by the Moghan irrigation network were calculated. The most important results of this research are presented below.The Crop Per Drop (CPD) index of rice shows the last level in the crop year 2019-2019 due to the amount of water consumed and significant cost. Also, in the analysis of BPD and NBPD index, this product has the lowest and ninth priority, respectively, and in the current water shortage conditions in the Moghan plain, there is a need to review the cultivation of this product. Tomatoes and fodder corn have good productivity in all three indices of CPD, BPD and NBPD in the crop year of 1399-1400. In fact, while tomato does not have a low water requirement, measuring the performance of this product shows the high net and gross profit obtained according to the cost of planting and harvesting.The amount of UWV index of wheat, rapeseed, soybean, rice, fodder corn, seed corn, tomato, barley, sugar beet, cotton, and peanut products is 24269, 15644, 18894, 9956, 36279, 17362, 50073, 23010, 21748, 19403 and 45718 rials per cubic meter, respectively. The proposed approaches and models of this research are different depending on whether the index of physical productivity or economic productivity of water is considered in planning and policy-making.

Watermelon is a popular fruit that is cultivated in greenhouses and on the ground, and water and fertilizer, as two essential factors for the growth of the product, significantly affect the yield of crops. However, water resources are scarce and irrational irrigation and use of fertilizers are common. This caused environmental pollution and waste of resources and also affects the growth and absorption of nutrients. Plant absorption, therefore, affects the yield and quality of the product. China is the first producer of this product in the world with the production of 67% of the total watermelon crop. The next ranks with less than 4% of world production are held by Turkey, Iran, Brazil and Egypt. According to FAO statistics, Iran ranks third in the world in watermelon production. In Iran, 91,000 hectares are cultivated with watermelon, of which 85,400 hectares are irrigated.Considering the special attention given to the watermelon plant as one of the high consumption options in the cultivation pattern, it was necessary to conduct a research in this field to investigate the amount of water required and reduce its yield under deficit irrigation.

In this study, Charleston variety watermelon was grown with a density of 8000 plants per hectare on June 8, 1401 in the soil and water research farm in Alborz province. Also, Crimson Sweet cultivar with a density of 11,000 thousand plants per hectare was cultivated on January 4, 1400 in the southern research center of Kerman province.In this regard, a research was conducted in the form of randomized block design in 4 full irrigation treatments, 75% of water requirement, 50% of water requirement and 30% of water requirement in the research farm of the Soil and Water Research Institute and Kerman Research Center. After applying deficite irrigations in different treatments, the performance of each treatment was measured. Also, the water requirement values of watermelon were investigated using the water requirement system of the Soil and Water Research Institute of the country under standard conditions. Also, using two production functions, the sensitivity coefficients of the Charleston variety were determined.

Results and Discussion :

The results showed that the standard water requirement of watermelon in Karaj is about 488 mm and in Jiroft area of Kerman is 423 mm and it is in good agreement with the water requirement estimated by the water requirement system. On the other hand, the highest sensitivity coefficient occurred in the period of 60 to 80 days after cultivation in the middle period of growth and the recalibrated production function estimated the yield of the plant with appropriate accuracy in the applied stresses, which the statistical indicators of Charleston variety RMSE, NRMSE, MBE , d and EF were 497, 0.02, -119, 0.99 and 0.98, respectively, and the Crimson number was 568, 0.095, -536, 0.98 and 0.96 respectively, so the sensitivity coefficients and production function It is proposed to simulate the performance of both watermelon cultivars under water stress conditions. Also, the highest productivity was obtained in the low irrigation treatment of 70% and Crimson variety has higher water consumption efficiency. Therefore, this variety is recommended for watermelon cultivation with 70% less irrigation.

Conclusion:

Summarizing the results showed that the standard water requirement of watermelon in Karaj is about 488 mm and in Jiroft area of Kerman is 423 mm and it is in good agreement with the water requirement estimated by the NIAZAB system. the sensitivity coefficients and the production function presented for simulation The performance of both watermelon cultivars is suggested under water stress conditions. Also, the highest productivity was obtained in the low irrigation treatment of 70% and Crimson variety has higher water consumption efficiency. Therefore, this variety is recommended for watermelon cultivation with 70% less irrigation.Considering the special attention given to the watermelon plant as one of the high consumption options in the cultivation pattern, it was necessary to conduct a research in this field to investigate the amount of water required and reduce its yield under deficit irrigation. In this regard, a research was conducted in the form of randomized block design in 4 full irrigation treatments, 75% of water requirement, 50% of water requirement and 30% of water requirement in the research farm of the Soil and Water Research Institute and Kerman Research Center. The results showed that the standard water requirement of watermelon in Karaj is about 488 mm and in Jiroft area of Kerman is 423 mm and it is in good agreement with the water requirement estimated by the water requirement system.

Estimating the amount of irrigation water for plants is one of the important indicators of the planning of the agricultural sector, and the NIAZAB system was created to estimate the water requirement of agricultural and garden plants and has the ability to check the changes in the irrigation and irrigation water requirements of different agricultural and garden plants in the country. The purpose of this study was to compare the results of field measurement of the amount of irrigation water and sugar beet yield in field conditions with the estimation of NIAZAB system in 117 points, 16 cities in 2016. The results of comparing the field measurement results with the estimation of the NIAZAB system showed that the average amount of sugarbeet irrigation water in the field measurement method and the NIAZAB system is equal to 13088 and 13856 cubic meters per hectare, respectively, and the average yield of sugarbeet tubers in the measurement of the farm and the NIAZAB system was 71846 and 64206 kg per hectare, respectively.The average water productivity of sugar beet in field measurement method and NIAZAB system was equal to 5.8 and 4.9 kg/m3, respectively.The comparison results of the statistical analysis showed that the NIAZAB system estimates the amount of sugar beet irrigation water in the city division scale with the root mean normal error of 21% and the agreement coefficient of 0.89 compared to the field measurement and also, it estimates the yield of sugar beet tuber with a root mean normal error of 0.27% and a coefficient of agreement of 0.81 and the water productivity of sugar beet tuber with a root mean normal error of 0.34%. The efficiency coefficients of the model showed that the NIAZAB system provides acceptable results in determining the amount of irrigation water and the productivity of sugar beet water in the fields of the country. It can be concluded that the NIAZAB system has the ability to provide the amount of irrigation water required by the sugar beet plant in the whole country as well as in the agricultural field.Most of the regions of Iran are located in arid and semi-arid climates, the characteristic of this climate is dry and long seasons without rain. In these areas, the lack of water is one of the most important factors limiting the production of agricultural products, in such a situation, the competition for water is increasing with the increase in population, urbanization and industrialization, and on the other hand, the lack of water is aggravated by improper irrigation management in agriculture (Moravejalahkam et al. al., 2022). In the dry climatic conditions of the country, it will not be possible to provide water easily. Therefore, in these conditions, one of the basic solutions for the proportionality between agricultural water resources and uses, considering the economic and social importance of domestic cultivation of strategic crops, which is included in legal documents, including the Law on Increasing the Productivity of the Agricultural Sector and Natural Resources, approved by the Islamic Council of 2010 was also emphasized (APERDRI, 2016). Optimum use of water resources and management of water consumption is of particular importance for sustainable agriculture and increasing the efficiency of water consumption, and the requirement for optimal use of water resources is to know the amount of water needed to produce an economic product. Sugar beet (Beta-rulgaris) is one of the important economic products and supplies 40% of the world's sugar production (Doorenbos et al, 1979). The benefits of sugar beet cultivation are very important in the national economy and in temperate regions where most of the sugar factories are built. Currently, there are suitable conditions for sugar beet growth in many parts of the country, and the cultivation of this plant is done on a relatively large scale. According to the official statistics of Iran's Ministry of Jihad and Agriculture, the area under sugar beet cultivation in 2016 was equal to 142,821 hectares, and the average yield of sugar beet tubers in Iran was reported as 48.8 tons per hectare (Statistics of the Ministry of Jihad and Agriculture, 2016). Sugar beet is the most important source of sugar production in Iran, and sugarcane is in second place. But sugarcane is cultivated only in Khuzestan province due to special weather conditions (Rahimian and Asadi, 2019). Sugar beet is one of the crops that is cultivated on a large scale in the form of irrigation, and the supply of water required by the plant is one of the necessary factors of production (Mountonnet, 2002). The water requirement of the sugar beet plant is different based on different varieties and different regions (Kochaki, 1996). So that it is reported between 250 and 2700 mm in different regions of the world (Ebrahimi Pak 2019).The results of field measurements in 116 farms in 16 cities and eight provinces of the country with different irrigation methods and different irrigation water sources showed that the average irrigation water of sugar beet plant from the measurement method in the fields and the estimated water demand system is equal to 13088 and it was 13856 cubic meters per hectare. The results of the weighted average of sugar beet irrigation water which was estimated by the system equal to 13817.9 cubic meters per hectare and directly measured from the fields equaled 12805 cubic meters per hectare, and it can be concluded for the surface of 140 thousand hectares of sugar beet irrigated lands. The volume of irrigation water estimated by the water requirement system was 1.94 billion cubic meters and the volume of irrigation water measured in the field was equal to 1.79 billion cubic meters. The comparison of the results of the two methods showed that there is a difference of about 7.7% in the country.