نشریه مدیریت جامع حوزه های آبخیز
سال دوم شماره 4 (پیاپی 6، زمستان 1401)

Today, the occurrence of various events such as climate change, drought, flood, land subsidence, as well as the increase in population and the subsequent increase in demand in order to meet human needs, has caused many changes in the functioning of watersheds and the interaction of different ecosystems. In other words, excessive pressure on natural resources, unprincipled use of resources, and disruption of ecological balance in different watersheds have caused disruption, reduction of balance, and change in the behavior of watersheds leading to instability. The imbalance in the functioning of watersheds has caused various hydrological, ecological, economic, and social functions to face problems, and the role of local communities has decreased in the direction of sustainable development of watersheds, which requires the study, evaluation, and fundamental management of watersheds. One of the reliable management approaches accepted by the international communities is integrated watershed management (IWM), which plays an influential role in managing natural resources by prioritizing watersheds. Therefore, this research has tried to analyze the detailed-implementation studies of the Fakhran Watershed in South Khorasan, Iran, as an example of the detailed-implementation studies of the country based on IWM.

To carry out this research, the Fakhran Watershed was first visited, and the watershed conditions were examined from the viewpoint of hydrology, erosion and sedimentation, water resources, socioeconomic and cultural status, and the potential of local communities and ecosystems. Detailed implementation studies of the Fakhran Watershed were obtained from the General Directorate of Natural Resources and Watershed Management of South Khorasan Province. They were evaluated and compared based on the IWM structure in the country.

The research results showed that cultural issues, laws related to watershed management, upstream policies affecting local communities, and modern knowledge of watershed management in the soil and water protection field still needed to be seen in these studies. In the economic aspect, despite the existence of economic strengths in the region, very general solutions have been pointed out, and the potential economic capabilities of the Fakhran Watershed, such as barberry, saffron, and jujube agricultural products, have been overlooked. The assessment of social issues also shows that the social needs of different age groups of believers, issues related to women, customs and rich culture of the region, and similar things have yet to have a place in the executive studies.

Various human activities and the occurrence of natural phenomena have caused changes in the behavior and performance of watersheds and disturbed the ecosystems’ balance. Different studies and management scenarios have been carried out by the relevant organizations to improve the watersheds' conditions, which could have led to better results. In this regard, revisiting the detailed-implementation studies of the Fakhran Watershed indicates that none of the six principles of comprehensive management, including politics, economy, society, culture, law, and knowledge, have been adequately considered in these studies. Also, the principled implementation of engineering, biological and bioengineering operations without considering the six principles of IWM cannot be employed in the future as a suitable approach to solve the problems of watershed residents. Therefore, studying watersheds and issues related to watersheds should be minutely reviewed, and the IWM approach should be extensively used to advance the goals.

Monitoring meteorological drought, as the base of other droughts, is of paramount importance in water resources management. Kohgilooyeh and Boyer Ahmad geographical location is in the western south of Iran. Since Karoun, Maroun and Zohreh, as three important rivers, originate in the upstream of this province, assessment of drought seems to be necessary for the region. This study aims to evaluate the spatial and temporal variation of meteorological drought of the province using Standard Precipitation Index (SPI) index.

To do this, SPI of 1, 3, 9, 12, 24, and 48-month timescale intervals for each station was calculated. Then statistical properties of SPI with different intervals were computed and time series of the SPIs in all of the stations were prepared and visualized. Finally, spatial maps of the SPIs were prepared and evaluated.

Assessment of statistical properties of SPI in different intervals showed that in all of the 14 stations, wet and dry periods have happened, in such a way that their occurrence was frequent in a short period of time. The location (stations) of the most severe drought and wet periods with different intervals was also determined. Results showed that not only drought trend is different in the stations, but also at one station differs in various time scales. The spatial map of province drought showed that 1, 3 and 6-month drought intensity in western regions of the province is lower than the eastern regions. The intensity of drought in western regions, and drought extent, increases as SPI time scale varies from low to high. In most of the stations, frequency and intensity of droughts decrease with time scale increasing. In the evaluated duration, 1 and 3-month drought intensity is decreasing, 9 and 12 months is increasing, and 24 and 48-month droughts are going to initiated. Short-time drought assessment (1, 3, 6 and 9 months) showed that in the Darshahi, Chitab, and Ghalea Reaisy stations, deeper short times drought events have occurred. Long-time drought (12, 24 and 48 months) assessment showed continuous and long drought events in the region.

Kohgilooyeh and Boyer Ahmad is affected by short and long-time meteorological drought in different regions, which could be an alarm for Karoun, Maroun and Zohreh rivers stakeholders. Spatial SPI maps with different intervals could be used for forecasting meteorological drought for the agriculture uses, and also livestock and industrial location selection.

The concept of "breathing the forest" in Iran was first proposed by the Environmental Protection Organization in the early 80s. Specialists in biological sciences believe that by implementing this plan, the lost parts of the forests can be restored.They say that the forests of the north need a 10-year rest period during which the industrial exploitation of the forests in this area should be stopped and managed with full supervision. On the other hand, the opponents of this idea believe that abandoning the forest under any title is contrary to conservation. From the point of view of this group, the implementation of the plan to stop exploitation means the closure of forestry projects, while they believe that forestry projects are a tool for managing forest areas.

The purpose of this research is to investigate whether the plan in question from the point of view of different stakeholders such as natural resources departments, environmental departments, and the forest dwellers have been successful or not after several years of the implementation of the plan to stop exploitation in the forests of the north of the country. In this research, data on the amount of wood smuggling, the number of land use changes and encroachment on forest areas, the number of fires, and also the amount of wood supply to the wood and paper industries of Gilan province during the two periods before the plan to stop exploitation and after the implementation of the plan to stop exploitation were collected from the General Directorate of Natural Resources of Gilan Province. Then, the data were analyzed using the comparison of averages (t-test) in SPSS software version 26.

The results showed that the plan to stop exploitation in some cases shows a significant difference based on the reduction of damage such as cases of destruction and seizure of national lands, slashing and burning, cutting saplings, and the release of national lands shows a noticeable change (P- Value≤0.5. Also, the results of this research indicated that this project did not cause a significant difference compared to the past in terms of tree and shrub cutting, firewood and wood discoveries, and the number and area of fires (P-Value≥0.5). It can be stated that based on the studies and using the background of the research, the criteria in a questionnaire were provided to the forest science and engineering experts and they were given points according to the opinion of the experts and the main factors that were above 80 % had obtained the highest score and were identified as the main effective indicators. Regarding the second question of the research, it can be said that the secondary factors were extracted from the library sources and past research background according to the main factors, and they were given points according to the opinion of the experts, and the factors that were above 80% received the highest score andwere identified as influential indicators.

This research is particularly important from the point of view of creating a perspective for decision-making for managers in the field of forest management because it examines the effectiveness of plans and decisions, and this process can be repeated periodically to help decision-making. Finally, with the implementation of the forest rest plan, any harvesting of the forest will be stopped within 10 years, with the justification that the forest can repair the damage caused by illegal harvesting during this time. What is the main content of this idea or demand is to stop wood exploitation in the form of existing forestry plans. However, what adds to the importance of this issue is that if people who are not experts in forestry introduce a solution, it is rejected from a scientific point of view. We give the right environmentalists and those who sympathize with the forest to shout that the state of the forest is not good, but it is the responsibility of the forest experts to provide the solution. Since forest management covers a wide range of economic, social, ecological, and employment issues, this issue should be dealt with more sensitively and all aspects should be taken into account in this respect. Using the opinion of experts in this field and determining the desired hierarchy, criteria, and indicators in this regard can be a good solution for this problem. In order to achieve sustainable management, it is necessary to extract and examine the opinions of experts. The results of this research, which were taken from the experts and experts in the forest field, also showed that considering all the criteria and indicators, from their point of view, any plan in the forest with the names of rest and breathing does not have a scientific basis, and a revision in this field is necessary. Although all the experts have acknowledged the existence of disadvantages in the existing plans, they have considered the solution to be updating and fixing the disadvantages of the current plans.

Introduction :

Groundwater is one of the most important natural resources in the world. In the current situation, a significant part of Iran's consumption in the drinking sector is provided by underground water sources. In the last 20 years, salinization and reduction of groundwater quality have become one of the serious environmental problems around the world. This issue adds to the importance of proper management of groundwater consumption. Proper management of groundwater consumption is not possible without having sufficient knowledge of the distribution and expansion of saline and fresh groundwater and determining the processes influencing its evolution. Atmospheric precipitation and surface water, passing through different geological formations, dissolve the salts in them. Therefore, the chemical quality of underground water depends on the type of formation that passes through its empty spaces. Also, the time the water stays in the basement has an effective role in the quality and salinity of the water, because the longer the water stays in the sediments, the saltier it becomes.Groundwater in arid and semi-arid areas, especially in Yazd province, is the main and reliable source of water supply for various uses due to low rainfall and lack or absence of surface water sources. In order to check the condition of underground water, it is necessary to check the concentration and type of solutes in the water. One of the factors affecting the quality of underground water in Yazd province is the existence of destructive geological formations. Therefore, the purpose of this research is to investigate the relationship between the quality of underground water in Yazd province and the type of formations.

Yazd province, with an area of ​​about 737.54 square kilometers, is located in the central part of Iran's central plateau, between 29 degrees and 52 minutes to 33 degrees and 27 minutes north latitude and 52 degrees and 55 minutes to 56 degrees and 37 minutes east longitude. Yazd province is bordered by Semnan and Isfahan provinces from the north and west, Khorasan Razavi province from the northeast, Kerman and South Khorasan provinces from the east, Fars province from the southwest, and Kerman from the southeast. It varies from about 666 meters above the level of the open sea (Zarin sand desert near Aqda) to 4075 meters (Shirkoh peak). The present research is about investigating the impact of geological formations and units on the quality of underground water in Yazd province based on the statistics, information, and reports available in the Geological Organization using a 1:100000 geological map. In order to check the quality of underground water samples, 217 wells and aqueducts of Yazd Region Water Company's monitoring network in July 2013, the measured parameters of cations (sodium, potassium, calcium and magnesium), anions The main elements (bicarbonate, chloride and sulfate) present in water, electrical conductivity (EC), dissolved solids (TDS), sodium absorption ratio (SAR) and pH were used. To check the quality of underground water, sampling has been done in 18 regions of Yazd province. RockWorks 14, ArcGIS 10.3 and Excel software were used to draw and prepare maps.

To check the groundwater type of 217 sampled points in Yazd province, the average data of each region was used. By using the main ions, samples of the type of underground water in each region have been obtained in such a way that by separating the ions and their amount in each region and then implementing them in the Piper diagram, the type of groundwater in the region is obtained. As it is clear in Piper's diagram, the predominant type of underground water in Yazd province is chloride+sulfate and calcium+magnesium. These types cover the largest area in the plains and playas, which have limestone and marl. There is also carbonate type in the region due to the presence of granite formation heights that have better quality water. The interesting point in this graph is that none of the samples are in the fresh water category. The Piper diagram shows that the groundwater of the studied area is located in the hard and completely hard water type due to the existence of terrace deposits and new low-altitude foothill alluvial cones, which cover about 3,383,512 hectares of the entire area of ​​the region. According to the Wilcox diagram of the study area, C2S2 and C4S2 classes have the lowest and highest shares with 0.46 percent and C3S4 and C4S4 classes with 32.26 and 56.22 percent, respectively. According to the results of the Wilcox diagram of underground water in Yazd province, the water quality of the region is too salty and unsuitable for agricultural use. The results show that the high amount of salts is one of the problems of the water that is used for irrigation in this area. High concentration of salt in irrigation water can reduce the growth of crops or even prevent the growth of some crops, which results in soil decomposition and groundwater pollution. In such water, the growth of plants and their quality will be improved by increasing irrigation for washing or using intermittent water with low salinity and good drainage.

If there is a trend of pollution and over-harvesting of the underground water table in the region, in the next few years, with the increase of TDS in the region, the condition of the water in terms of drinking will become worse. The best quality of water for drinking is in the central and southwestern regions where the normal gneiss granite formation with eye grain structure is located in the mountainous area of Shirkoh, and the further we move away from the center, the worse the water quality is. The formation of these areas is of the type of terrace deposits and alluvial cones of new foothills.

With rapid population growth and increasing demand for food, water shortage is one of the challenges of development in countries, because more than 98% of the water on the earth is salt water. In addition, the use of some fresh water sources is also limited. Such a situation will worsen with time. This limitation is more in dry and desert areas that have little rainfall and their distribution is not suitable. The country of Iran, which is located on a dry belt and its rainfall is less than a third of the global amount, is one of those areas that is facing a lot of water stress. Due to the lack of rainfall in the country and, on the other hand, the lack of scientific use of the country's natural and agricultural areas, the ground has been laid for the destruction of natural ecosystems. Accordingly, due to the limited supply of fresh water for agricultural purposes in the world, especially in dry areas, saline water is widely used to irrigate crops to provide the water needed by plants. Due to the use of saline water with a high concentration of salt, especially sodium salt in the soil, it causes a decrease in production efficiency and destruction of the physical and chemical properties of the soil. Since most of the water resources are consumed in the agricultural sector, an appropriate irrigation pattern should be used to prevent soil degradation and erosion in addition to increasing crop yields. Clay pot irrigation is one of the methods that has a better performance than other irrigation methods such as surface and drip type. This type of irrigation is suitable in dry areas that have high evaporation and transpiration and are associated with water crisis.

In order to carry out this research, first, 36 holes with a depth of 60 cm and a diameter of 50 cm were dug, and in 18 holes, a clay pot was placed with a height of 40 cm and a diameter of 5 cm, and 18 holes were selected as control and without clay pot. Three soil samples were taken from a depth of 50 cm at the beginning and at the end of the research period. Soil changes were made by irrigation with saline water and the characteristics of pH, EC, Na, SAR, organic matter, P, K, Ca, Mg and soil texture were measured. Considering that three types of water with different salinity (1200, 2200 and 3200 umho/cm) were used, three sources of water each with a volume of 200 liters were placed beside the location of implementation. By using the variety of saline water that existed in this area, bringing the EC of water to the level required for the research was done in the laboratory and stored in the relevant water sources. Cultivation of two plants, Rosa damascena and Hibiscus sabdariffa, was tested. Soil moisture (by weight) was measured monthly at a depth of 60 cm.

Examining the pH of the soil samples shows that there is not much difference in the value of this characteristic of the soil of the research area, such that the range of this characteristic varied between 8-8.4. Changes in the EC of the investigated area at the beginning of the project fluctuated between 4.4 and 5.2 mg/liter. After the implementation of the saline water plan, it has been affected, such that the range of this feature has been varying between 16.5-9.7 mg/liter. Measuring the amount of Na at the time of starting the work showed that the range of changes fluctuated between 43.3-43.85 mg/liter. Total Ca and K were measured as 19.7-24.2 mg/liter, while the amount of this feature changed between 26.5-18.4 mg/liter after the completion of the project. The amount of SAR of soil samples at the beginning of the implementation of the project was between 13-3-17, but after the implementation of the project, this range changed between 12-7-18-4. The range of total cations of the soil samples collected at the beginning of the research varied between 43.5-43.5 mg/liter. But after the end of the project, this range changed to 103.5-72.8 mg/liter. Examining the texture of the soil samples at the start of the project showed that the range of clay changes varied between 14-15%, but after the completion of the research, it changed between 10-14%. The amount of silt in the soil samples at the time of starting the project was 43-47%, while this value changed to 44-48% in the samples after the end of the plan. Examining the amount of sand in the soil samples at the beginning of the research showed that the range of changes was between 42-39%, which did not change at the end of the project.

In this research, the effect of two irrigation methods with saline water on soil moisture and physical and chemical properties was investigated. The results showed that compared to the average of all characteristics, clay pot irrigation performance was better. The work process in this irrigation method is such that the clay pot plays the role of a filter and suitable water is provided for the plant. In this type of irrigation, the transfer of water is limited to the area of ​​the plant's roots, which causes an increase in soil moisture in this area, and improves the plant's performance. In other words, the distribution of moisture in the soil during percolation clay irrigation is such that the water enters the root area of ​​the plant uniformly, which, in addition to meeting the water requirement, also reduces the temperature of the soil. But in drip irrigation, moisture is placed on the soil surface, after which the moisture spreads horizontally on the soil surface and the water does not penetrate deep into the soil. This situation causes evaporation and transpiration to increase and plant roots face water stress. Also, soil solutes cause the soil to become salty through evaporation. In addition, water salinity also increases the intensity of soil salinity, which leads to soil degradation and erosion. Therefore, for the continuation of exploitation in dry and desert areas, it is necessary to use the appropriate method of irrigation in order to sustainably exploit the land without harming its ecosystem components, including the soil. Therefore, according to the existing methods of irrigation, the clay pot type is more important than other types of methods. It can thus be concluded that due to the lack of fresh water resources in Sistan and the limited flow of water from Afghanistan and the existence of subsurface saline water sources, it is necessary to use them, that the use of clay irrigation method has a positive effect on the vegetation and the improvement of the environmental situation and the continuation of exploitation.

In recent decades, following the exploitation of groundwater, especially in areas with limited surface water and in which groundwater is the greatest resource in meeting the needs of water demands, the trend of reducing the volume of aquifers has increased. Meighan watershed, which includes Meighan wetland, is one of the most important plains of Iran that supplies a significant part of Arak city's drinking water and many agricultural wells. Since the drought causes a rapid reduction in surface flows, declines the ground water level, intensifies the wind and water erosion, changes the quality of water resources, causes ground settlement and especially, leads to the problem of salinization of drinking and irrigation water, it is necessary to evaluate the effects of drought and manage its risk.

The study area of Meighan is located in Central Iran with 2854.63 km2 area. To investigate the possible drinking water crisis in the region, water level decline of agricultural wells, and the risk of ground settlement in the groundwater measurement network, the observed groundwater level and absolute height of groundwater level data were collected in 46 piezometric wells in the statistical period of 1986-2006 and 2006-2020. For each year, an average isopieze map was drawn. Then by deducting the maximum and minimum values in each well, the amount of loss in each year was determined. These data were used to draw maps of annual decline. The reason can be the lack of proper feeding of the aquifer due to the decrease of precipitations and drought and as a result of the reduction of the aquifer storage due to the excessive exploitation.

From 1971 (the first data collection) to 2004, with the increase in the number of deep and semi-deep wells, the discharge rate of the wells has increased by a total of 531.5 mm3. In 2009, despite the increase in the number of wells, the discharge rate of wells has decreased by 153.9 mm3 in 6 years. In the last data collection in 2020, the number of wells and their discharge rate have decreased which indicates drying up of the wells due to the decline in the groundwater level in many areas of the plain which has led to the disuse of wells.Reviewing the decline maps of 1986-2006 and 2006-2020 indicate that the northern and eastern areas of the plain do not show significant changes and have a relatively constant trend. However, as it is shown in isopieze maps, in the western regions and in the south of the plain, groundwater level has had the highest decline. From 2006 to 2020, in the north and northeast, as well as in the south, west and southwest of the basin, there are areas with the highest rate of decline.

According to the analysis of rainfall data and the absolute height of groundwater level of Arak Plain, it can be concluded that the amount of rainfall does not directly affect the decline of the groundwater level. Research results indicate that before 1986, the hydraulic slope of the Arak plain aquifer conforms to the level of the plain and the Meighan playa has been a natural drainage of the plain. However, during the period of 1986-2006 with the increase and concentration of exploitation wells in the western and southwestern parts of the plain, the hydraulic slope of the aquifer has inclined towards the western regions. From 1986 to 2006, it can be concluded that the maximum groundwater level decline of 20 meters occurred in the western and southwestern areas of the basin and extended to the eastern areas of the basin. However, from 2006 to 2020, the decline classes have increased significantly, such that in the west, southwest, north and northeast of the basin, an increase in the groundwater level decline up to 70 meters has been observed.