Negar Tayebzadeh Moghadam; Bahram Malekmohammadi
Abstract
The response of water balance components as indicators of hydrological performance to stimuli such as land use change is of strategic importance. In this study, the effect of land use change on water balance components was evaluated, focusing on the relationships and change of the main indicators of ...
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The response of water balance components as indicators of hydrological performance to stimuli such as land use change is of strategic importance. In this study, the effect of land use change on water balance components was evaluated, focusing on the relationships and change of the main indicators of water yield and sediment yield. Based on this, the Markov chain model was used to predict land use in 2040. Also, the American soil and water assessment tool was developed as a base model for evaluating and estimating hydrological indicators in the Taleghan Watershed as a mountainous watershed with structural heterogeneity. The results of model showed that the increase of settlements and urban development in Taleghan watershed will result in increased runoff, increased water yield and sediment yield indicators, and more sedimentation. Land use change leads to an increase of sediment yield by 11 times until 2040. The conversion of pastures to barren lands is the most important land use change that can increase sediment yield. Also, the increase of barren lands will be the reason for the reduction of evapotranspiration in some sub-basins of this watershed. Increasing rainfall and decreasing soil permeability will increase surface runoff, and as a result, soil erosion and sediment yield will increase. In this study, exactly the sub-basins that had the highest quantitative amount of predicted water yield index also had the highest quantitative amount of sediment yield index and increased sedimentation. In this research, it was determined that land use change as a type of structural change in the land will have visible effects on the functions and hydrological responses of the watershed.
Mohsen Adeli Sardooei; Ali Asadi; Khalil Khalil; Ali Akbar Barati; Hassan Khosravi
Abstract
Evaluating of the development of crops based on water needs along with detecting and predicting land use changes will provide a clear picture of changes in water resources and anthropogenic effects of the agricultural sector for environmental planners to plan more consciously in the field of water and ...
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Evaluating of the development of crops based on water needs along with detecting and predicting land use changes will provide a clear picture of changes in water resources and anthropogenic effects of the agricultural sector for environmental planners to plan more consciously in the field of water and soil conservation, Therefore, the current study was conducted with two general objectives. The first goal was to examine land use in the past and predict land use in the future using the Land Change Modeler (LCM) and logistic regression method. Detecting land use changes was performed using Landsat satellite images including sensors of TM (1990), ETM+ (2001) and OLI (2019). The second object of the study was to examine the development trend of agricultural products in terms of water needs in the last three decades, which was examined based on databases of the Agricultural Jihad Organization (AJO). The transition potential modelling was performed based on logistic regression method and variables of digital elevation model (DEM), slope, aspect, geology, the distance from fault, the distance from road, the distance from river, distance from residential lands, NDVI and land use was predicted using Markov chain in future. Also, the trend of changes in the area under cultivation of major crops based on water needs in Jiroft plain was studied based on the data of the last three decades and the data of the National Irrigation Document, which has been less considered by researchers in land use change studies.
Leila Zandi; Reza Erfanzadeh; Hamid Joneidi-Jafari
Abstract
This study aimed to determine the effect of land use changes from rangeland to horti-agricultural lands on the most important qualitative characteristics of soil such as total soil carbon and particulate organic matter, in Salavatabad region, Sanandaj. In the present study, one rangeland, two cultivated ...
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This study aimed to determine the effect of land use changes from rangeland to horti-agricultural lands on the most important qualitative characteristics of soil such as total soil carbon and particulate organic matter, in Salavatabad region, Sanandaj. In the present study, one rangeland, two cultivated pea lands, two cultivated wheat lands and two gardens were selected in growth season in the end of spring, 2014. Forty two soil samples were taken randomly and systematically from the study region. Then, soil micro- and macro aggregates were separated using 0.25 mm and 2 mm sieves. Total soil carbon and particulate organic matter of soil samples were measured in the laboratory. The results showed that land use changes from rangeland to horti-agriculture significantly decreased total carbon and particulate organic matter in micro-aggregates. While total carbon and particulate organic matter in macro-aggregates was not changed by land use changes from rangeland to horticultural land. We suggested that if rangeland will be converted into agricultural land, horticultural land is the best for land use changes.
