سیستم اطلاعات جغرافیایی

Rainfall is a predominant climatic element that affects the density and location of agricultural systems as well as the choice of farming operations. The distribution, intensity, duration, and type of rainfall are very important at different stages such as cultivation, emergence, tillering, stem formation, and flowering. Kurdistan province has regular rainfall with an average rainfall of more than 500 mm per year. Therefore, Kurdistan province is one of the most prone rain-fed areas in Iran. As well his province with an area under cultivation of 120,000 hectares is one of the most important areas of chickpea growing in the country. However, the distribution of rainfall is not the same in all regions of this province, and therefore it is necessary to study the potential risk of chickpea production in Kurdistan province.

Long-term climatic data were collected from 15 stations for a period of 20 years from 1991 to 2011. The results of spatial and temporal analysis determined the climatic-agronomic indices of the suitable region and the amount of dryland chickpea production. Kurdistan province was divided into three climatic regions; High-risk or unsuitable climatic-agro-area (0.23% of the total area), medium-risk area or with relative proportion for production (59.71% of the total area), low-risk or suitable climatic-agro-area (37.96%) From the whole area).

The results of spatial and temporal analysis determined the climatic-agronomic indices of the suitable region and the amount of dryland chickpea production. Kurdistan province was divided into three climatic regions; High-risk or unsuitable climatic-agro-area (0.23% of the total area), medium-risk area or with relative proportion for production (59.71% of the total area), low-risk or suitable climate-agro-area (37.96%) From the whole area). The results of the study on the relationship between rainfall of vegetative stage and the potential of cultivation of dryland chickpeas in the region show except for a small part of Qorveh, Bijar, and Sarvabad cities which are in a weak degree. The whole region is in a very good degree in terms of supplying the required moisture, which is also due to the necessary rainfall at this time and the humidity of the storage capacity stored from the winter rains. The occurrence of suitable precipitations for the vegetative period in the whole region had the highest value compared to other developmental stages. The results of the study between the relationship between reproductive stage rainfall and cultivation potential of rainfed chickpeas in the region showed that Zarrineh station in the north of the region is weak due to unfavorable weather conditions at the beginning of the growing season and the developmental stages of the growing season in this region are delayed. At Zarrineh station, the critical reproductive stage occurs at a time of year when the probability of precipitation in Kurdistan has actually decreased and a part of the southeast of Qorveh city is one of the weak and critical areas. The rest of the province in terms of moisture supply for this stage of dryland chickpea development is in a suitable degree, which is due to the necessary rainfall in this period of development.

The results of the study show the relationship between rainfall of vegetative stage and cultivation potential of dryland chickpeas in the region, except for a small part of Qorveh, Bijar and Sarvabad counties, which are in a weak degree. The whole region is in a very good degree in terms of supplying the required moisture, which is also due to the necessary rainfall at this time and the humidity of the storage capacity stored from the winter rains. Occurrence of suitable precipitations for the vegetative period in the whole region had the highest value compared to other developmental stages.

Land use/cover change is one of the main factors in environmental changes. The changes directly affect the value of ecosystem services. The purpose of this research is to evaluate the effect of land use/land cover change in the Kashkan area on its ecosystem services. This research was carried out in three stages, including the analysis of land cover changes, prediction of changes, and carbon storage and sequestration. Landsat satellite images of TM, ETM+, and OLI sensors were used to prepare land cover maps in three periods of 1370, 1385, and 1400. In the TerrSet software environment, LCM modeler was used to predict land cover change in 1430 and ESM modeler was used for carbon storage and sequestration. Carbon storage data were extracted from IPCC emissions. Validity was evaluated using an error matrix. The results show that forest ecosystems have had the most land cover changes and the most hot spots of carbon loss are in forests. In 1370, about 44.35% of the area, equivalent to 4113.8 square kilometers, was made up of forest ecosystems, while in 1400, it decreased to 26%, equivalent to 2411.7 square kilometers. According to the future study scenario in 1430, about 1205.8 square kilometers of the area will be forest ecosystems, and between 1400 and 1430, about 158,000 mg of carbon will be released. The results can be used by environmental planners and managers to improve and protect the natural covers, especially forests, to protect ecosystem services and their continuity.

Despite the importance of mangrove forests, mismanagement and insufficient knowledge about the environmental factors affecting these ecosystems is the first step in their sustainable management. In this research we extracted the drainage structure of watersheds from the digital elevation model (DEM) by 30 meters cell size and the 81 basins on the coastline of Hormozgan province were identified and partitioned. Then 22 morphological variables for each watershed were calculated using computational methods and geographic information system software features. In the next step, the principal component analysis (PCA) used for dimension reduction and feature selection to investigate the correlation between the formation of mangrove forests and upland watersheds characteristics. Based on principal components analysis results six watershed variables identified as independent variables and entered to the regression model. The results showed 93.21% of the variance of the dependent variables explained by these six variables which including: equivalent circle diameter, time of concentration (Kirpich method), Horton coefficient, the maximum elevation and the main stream variables. The equivalent circle diameter was the first effective factor and had a direct relationship while the Kirpich time of Concentration and Gravelius or compactness coefficient were also considered as very important factors with an inverse effect on the presence and area of mangrove forests downstream. Generally, the results of this study indicated a strong systemic relationship between upstream watersheds and coastal and downstream mangrove ecosystems, and in the management and protection of these ecosystems, the characteristics of the upstream watershed should be considered.

Fires in Iran's western forests (semi-arid oak forests) are one of the main dangers in this region, which causes irreparable damage to ecosystems and the environment every year. Therefore, determining and predicting high-risk areas of fire helps to minimize the occurrence of fire and its damage by using fire risk models. The forests of Dalhu County (Kermanshah province), which are considered in the category of semi-arid oak forests, face this crisis every year and many forests prey to fire. In this research, identification and classification of high-risk areas of fire and preparation of map of high-risk areas of forest fires using Geographic Information System (GIS) and Analytical Hierarchy Process (AHP) in the forests of Dalahu County have been done. In order prepare a map of the high-risk areas of fire in the research area, influential factors such as forest cover density, Normalized Difference Vegetation Index (NDVI) evaporation (mm), slope and direction (degrees) and elevation above sea level.meter were used. The final map was grouped into five different categories of very low, low, medium, high and very high. Finally, the results showed that Dalahou's forest fires are include areas with very low risk 14.17%, low risk 32.48%, medium risk 33.43%, high risk 17.19% and very high risk 2.7%. The results of this study can be used for sustainable development policy at the levels of natural resources and environment.

With increasing population growth and increasing waste production, the need to determine the appropriate landfill for waste has increased. Therefore, the need for planning to determine the appropriate location for sanitary landfill is very important and menstrual. The use of Geographic Information System (GIS) tools and Analytic Hierarchy Process (AHP) are one of the most effective tools for selecting landfills. The purpose of this study is to locate the suitable landfill for Sahneh County. In this research, slope, distance from river, land use, distance from road, distance from fault have been used to determine the landfill. In order to locating the landfill GIS for extraction and necessary processing and from hierarchical analysis (AHP) used to measure criteria. The final weight in Analytic Hierarchy Process is given the highest score to the distance of the roads and the lowest score to the distance from the river. Based on the findings of this study, landfills in the study area can be classified into five categories. Very suitable areas for landfilling are> 20% slope, distance from roads 10000-20000 meters, distance River <6000 m, distance from fault <7000 m, land use of rocky outcrops with an area of 8139.79 hectares and 59.5% have a higher priority for landfilling in compliance with health and environmental standards and laws. Also, the analysis of the results of this study shows that areas designated for suitable landfill have highly desirable.

With the global expansion of population, rising energy consumption and the lack of renewable energy sources that are costly and polluting, the need for clean and sustainable energy such as solar energy has been increasingly taken into consideration. To evaluate land suitability for the optimal placement of photovoltaic solar power plants in Yazd province of Iran, the analytic hierarchy process (AHP) was used. A set of climatic and environmental constrains based experts' advices prepared in nine layers, estimates the potential sites for solar park installation. These constrains based on their relative importance in site evaluation extracted from AHP method, including sunshine, humidity, rainfall, evaporation, temperature, elevation, distance to access, fault and the power post. Climatic data obtained from eleven synoptic stations including fifteen-year period (2001-2016). After final mapping, the susceptible areas of photovoltaic solar power plants were determined in Yazd province. These areas located in Yazd, Bafgh, Ardakan, Meybod, Saduq and Khatam cities. After applying the privacy layer and considering the forbidden areas by conducting the field surveys, 5% of the Yazd province was considered suitable area for the construction of photovoltaic solar power plants. These areas are located in the south and south-east of Yazd, and part of the Bafg city.

This study was aimed to predict the potential distribution of Ferula ovina (Boiss) in Feridoonshar, in the western part of Isfahan province, and to produce species response curves in relation to the environmental variables using the Generalized Linear Model (GLM). The presence and absence of the species in 278 sites (including 138 presence sites & 140 absence sites) were collected using random stratified sampling. Digital elevation model was used to produce elevation classes, aspect and slope maps. Seventy soil profiles and 10 climate stations data were used to produce 31 environmental maps including climate and soil maps using kriging methods. According to the results, the presence of Ferula ovina was correlated with silt percent, average annual temperature, elevation, organic matter content, soil saturation percentage and CaCO3 content. The produced species distribution model had high accuracy, as indicated by calculated Kappa coefficient (0.79) and ROC area under curve plots (0.83). The result of this study can be, therefore, used in the rehabilitation and restoration of this valuable species in the rangeland ecosystems.

The northern coast of the Persian Gulf has undergone severe morphological changes due to its oil and gas reserves and its connection with free waters more. it is essential to determine the coastline at different times. Landlord satellite data from 1996 to 2016 was used to survey the changes in the coastal area of Asalouyeh to the Bandar Deir, and to prepare a five class including vegetation, water, man-made, rangeland and no agriculture. For each user, the area of calculation and changes were revealed and compared with the obtained data. The statistical analyzes for the 20-year were supervised by maximum likelihood and were used to determine the changes in the comparison method after classification and the maximum probability algorithm. The results showed that the area of human land was built and no agriculture increased from 1996 to 2001, and the area of vegetation, water and rangelands decreased during the period from 1996 to 2016, which coincided with the development of the South Pars oil field, and overall, the largest increase in total use was with %393. Between 1996 and 2016, vegetation use decreased by a total of %47 and a large amount of vegetation was made into human use.

Soil erosion is one of the most important issues that human is facing now. The purpose of this research is to estimate the soil erosion in Iran using the RUSLE model and use of geographic information systems (GIS) and remote sensing data (RS). In the present study, after collecting and gathering various information including the digital elevation model (DEM) layers, Statistics on weather stations and rain gauges, satellite images and soil characteristics were used as research tools and Soil erosion was estimated using the RUSLE model. The average annual values of P, K, C, LS and R factors are 0.65, 0.04 (t h MJ-1 mm-1), 0.46, 3.6 and 195 (MJ mm ha-1 y-1 h- 1), respectively. The results of this study showed that the average annual soil erosion in Iran is about 24 tons per hectare per year. Also, the results of the study showed that about 4 billion tons from soil the country eroded and partial entered the system of water in the stream and the sea which reduces the quality, water pollution, reduces of soil fertility and reduces the amount of cultivated land and ultimately leads to soil degradation.

IntroductionClimatic conditions are the most effectiveness than from the natural environment variables for agricultural production On the other hand the base of agriculture development, especially in semi-arid zone is the accurate knowledge of environmental characteristics and its management practices. Cotton (Gossypium hirsutum L.), due to the extensive roots and permeability and the ability to set the number of leaves and fruits under water stress, is a suitable crop for planting in arid and semi-arid climates. South Khorasan Province is a dry, desert and mountainous region with post-semi-arid and semi-arid climates. South Khorasan province produces 34000tons of cotton annually with 13000 hectares of irrigated cotton lands and the second position in cotton production ranking in Iran.
Materials and MethodsSouth Khorasan Province is located in the east of Iran with an area of 149,107 square kilometers and the geographical coordinates of 30 degrees and 31 minutes to 34 degrees and 53 minutes of northern latitudes and 57 degrees and 3 minutes to 57 degrees and 60 minutes of eastern longitude. This study was performed to evaluate the climatic conditions for the cultivation of cotton in the history of different cultures in South Khorasan province in a 25-year period (1990-2015). For this purpose, fifteen stations of South Khorasan province was chosen as target and modeling and spatial analysis was performed by Arc GIS. By using advantage of favorable climatic conditions at each stage of cotton growth, was prepared data layers of classification and weighting values for each of the zones. Eventually, in order to overlay layers using multi-criteria decision-making methods based on the Analytic Hierarchy Process (AHP), the final maps was prepared for each date based on the climatic factors of the cotton cultivation date in South Khorasan.
Results and DiscussionAccording to the results obtained from zonation of different cultivars, in the western and southern parts of the province, the suitable planting date will be from the first to second half of the April. This is while the planting date in the central and northern regions and some parts of the south of the province will continue from the first month of cultivate (March) to the first half of the second month until the first half of May. In the eastern parts of the province, suitable planting dates will continue from the second half of June to the first half of July. Considering the cotton ecological needs, if the plant cultivated in suitable planting date in different regions of the South Khorasan Province, there will be no growth inhibitory temperatures for this crop. The results of all cultivar maps indicate that among all planting dates from April to July, the best cultivation date was the first half to the second half of May, because they have the largest area in terms of area of suitable areas. The first half of July, due to lack of rainfall and temperature increase, is not a suitable time for flowering stage of cotton, because of it will be treated at a lower temperature when it is processed. Therefore, just with the reduction of the product. For cultivation of cotton in the first and second half of April the appropriate areas are western and southern regions of the province.
ConclusionThe results was showed that the role of temperature and precipitation as climatic factors, were difficult for any cultivation date in different regions and cultures of all dates from April to July. The best planting date from the first half and the second half of May, because of, respectively, 84,680 and 103,100 square kilometer area of the right to have the largest area. For all climatic conditions also have an important loss condition.

Increase of population, limited resources and the excessive exploitation of aquifers and surface water caused irreparable damage to the country's natural resources including groundwater resources. Contamination of groundwater has been published in numerous environmental hazards that directly affect their life. The aim of this study was to evaluate the quality of groundwater for drinking and irrigation purposes in the Saghez city, Iran. For this purpose, 188samples has been gathered from 2004 to 2012 water data and the parameters of salinity, chlorine, concentration of dissolved substances, sulfate, Nitrate, water hardness, sodium adsorption ratio were studied. Analysis of variance (ANOVA) and the LSD test was used to compare treatments and the differences between various stations respectively. For determining the most appropriate location and zoning methods for the above parameters, geographical information system (GIS) was used. Therefore, a geostatistic method of Circular Kriging, Gaussian and deterministic techniques such as inverse distance weighting, local estimator and general estimates was applied. The results showed that the quality of water in the Saghez city is appropriate and acceptable for drinking and irrigation. Spatial interpolation results according to the root mean squared error (RMSE), Mean Bias Error (MBE) and mean absolute error (MAE), among the different methods of interpolation techniques the IDW with 1 power for estimating the parameters of sulfate, sodium, chlorine and sodium absorption ratio, and the IDW with 2 power for estimating parameters of salinity, soluble solids concentration and total Hardness and the Circular Kriging method were the most appropriate methods for Nitrate.

In recent years, paying attention to groundwater and management, It's extraction due to lack of surface water and population growth, agricultural development has increased.This source is considered as one of the valuable resources of freshwater so that this source has become one of the most valuable vital resources. Groundwater extraction in recent years caused to down the level of this water. So that is reached to amount of 19.9m in the plain of qorveh since 1986,1987 until 2015.so that the plain has become one of the forbidden plains of 625 plain country. In recent years, integrating data of remote sensing (RS) and geographic information system(GIS) has increased for exploration this valuable material. So that the combination of these two has become a point in the field related to the issue of water. In this study with help of (RS) and (GIS) data potential areas of groundwater were identified. Layers that were created for site selection of aquifer in this study are as follows: geology, topography, slope, lineament, density of lineament, drainage, density of drainage, land use and vegetation of cover. At last the final map with help respective layers obtained with method of fuzzy in gis. The resulting map was divided to five groups very good, good, average, weak and very weak. The results showed the areas with good and very good potential with an area of 136461 hectare which about half the area of plains in more northern parts and accordance with alluvial lands with vegetation of cover and down slope and regions with lower potential more in southern parts and matches the slope area covered with rock solid.

Ajabshir Plain is located in the eastern Azerbaijan province and in the north-west of Iran. This plain provides the water for drinking, agriculture, and industry in Ajabshir city. In this research, regarding the hydrology and hydrogeology conditions of the study area, the vulnerability of the aquifer against the pollutants was zoned using DRASTIC and SI models and geographical information system. In DRASTIC model 7 factors including depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone and hydraulic conductivity are used to generate the vulnerability map. The vulnerability assessment of aquifer is also affected by 5 factors including depth of groundwater, net recharge, lithology of the aquifer, topography and land use in the SI model. After preparing information layers and rating in ArcGIS software, the final map of aquifer vulnerability to pollution was prepared through integrating layers. Regarding the SI vulnerability map, about 2.24% of the study area is located in very low vulnerability area, 5.27% in low vulnerability area, 45.08% in moderate to low vulnerability area, 39.09% in moderate to high vulnerability area, and 8.3% in high vulnerability area. According to the DRASTIC model, 13.4% of the study area was allocated to very low vulnerability, 55.43% to low vulnerability, 28.69% to moderate to low vulnerability, and 3.08% to moderate to high vulnerability. The evaluation of two models by TDS element indicated that SI model (correlation coefficient= 0.76) is more accurate than DRASTIC model in terms of preparing vulnerability map for the study area. Moreover, both prepared vulnerability maps showed that conservation of groundwater resources of Ajabshir plain by managers and planners is necessary to control and prevent the aquifer from pollution and its stability for the future generation.

Hydropower power generation is one of the most important sources of renewable energies. Small hydropower plants are becoming the most popular option of hydropower plants, which can be applied in small and remote places, and are able to produce cheap, clean and reliable electricity. In Iran and most developing countries, electricity transmission to remote regions for reasons such as high transmission costs and lack of proper supply of electricity, is faced with serious problems. Therefore, small hydropower plants can be considered as a suitable option to supply the power needed especially in rural and remote areas. This study aimed to study the feasibility and potential for generating electricity from small hydropower plants in the province of Kurdistan. Therefore, the catchment areas have been investigated and based on the average of tempreture, rain fall, and the catchment areas the amount of discharge is estimed. Then an appropriate locations to install hydropower plants are determined with respect to the intended technical, economic and environmental restrictions. Finally, the capacity of hydropowers is calculated. The results indicate the possibility to construct 3455 small hydropower plants in the province of Kurdistan, and finally, in the case of construction of small hydropower plants, in all the proposed areas it will be possible to produce 492 MW of electricity from hydropower in Kurdistan.

Basins leading to Tabriz plain are part of the sub-basins of Urmia Lake basin, which is located in the east Azerbaijan province and in the north-western part of Iran. The area of this basin is 5397 km2, and Agriculture is one of the main sources of income for the people, which is dependent on groundwater and surface water resources. In this study, an attempt was made to investigate the basins leading to Tabriz plain in terms of potential detection of the groundwater resources using GIS. To achieve this aim, analytic network process and relationships between climate, hydrology, geology, topology, and environmental criteria were applied. Weights of criteria were calculated by analytic network geology (0.267), precipitation (0.208), stream density (0.130), vegetation cover (0.119), distance from stream (0.076), fault density (0.054), slope (0.042), distance from fault (0.034), elevation classes (0.028), aspect (0.019), and temperature (0.018). Finally, 5 potential classes including, very high, high, moderate, low, and very low were identified in the study area. The results of the study indicated that regions with high and very high potential often correspond with low elevations and alluvial large grain sediments of fourth era and fans. Also, low and very low potential regions respectively correspond with maximum heights (due to steep slope), and marl and shale regions (due to very low penetranceand high evaporation).

Baghe-shadi in Yazd province is one the forests which is reported to be an area with high rate fire occurrence. The aim of this study was to model and map the fire risk area using geographic information system and remote sensing. In this study Analytical Hierarchy Process (AHP) with human related factors (distance from road, distance from settlements, and distance from vegetation), climatic related factors (air temperature and rainfall), and physiographic related factors (elevation, slope, aspect) were selected. Vegetation cover was estimated using Landsat OLI Normalized Difference Vegetation Index (NDVI). Weights were determined from specialists through questionnaire. Weight of each factor, elevation, slope and aspect, temperature, precipitation, distance from roads, distance from settlements and vegetation cover was achieved through multiple criteria decision making model, then areas with five susceptible classes were determined using GIS. Results showed that vegetation related factor and human related factor with weights of 0.569 and 0.204 are the most important factors respectively. In order to assess the accuracy of developed model, fire susceptibility map of was compared with the previously fired area. Result of comparison showed very high and high risk areas are corresponding to the controls area. Receiver operating charasteristic (ROC) test confirmed the high level (0.88) of accuracy of presented model.

Species distribution maps have been widely developed based on ecological niche theory together with statistical and geographical information system in plant ecology. The current study aimed to evaluate Artificial Neural Network (ANN) in mapping potential habitat of Ferula ovina Boiss in Ferydunshar rangelands، Isfahan. This is known as valuable forage and medicinal species. Environmental data (independent variables) and species occurrence data (dependent variable) were required to determine potential habitat of a given species. Some physical and chemical soil properties، climate and physiographic variables were mapped for the entire studied area using krigging and inverse distance weighting methods. F. ovina occurrence data were collected from 278 sites including 137 presence and 141 absence sites. The relationships between the studied environmental variables and F. ovina occurrence data were explored using ANN method. According to the sensitivity analysis، occurrence of F. ovina mostly correlated with silt and sand percentage، elevation slope، and organic matter. Model evaluation based on Kappa coefficient (0. 66) and Receiver operating characteristic (ROC=0. 9) showed good model fitness in relation to reality on local scales. The ANN technique enables managers to identify appropriate areas for rehabilitation practices such as direct seeding and planting.