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.
Farnoosh zareii; Hamed Joneidi; Parviz karami
Abstract
This research was carried out to evaluate the effect of rangeland conversion to afforestation with Cupressuss arizonica and Celtic caucasica on soil carbon emission. In order to determine the rate of carbon and carbon dioxide emission by tele-alkaline method with a stacking chamber, monthly was performed ...
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This research was carried out to evaluate the effect of rangeland conversion to afforestation with Cupressuss arizonica and Celtic caucasica on soil carbon emission. In order to determine the rate of carbon and carbon dioxide emission by tele-alkaline method with a stacking chamber, monthly was performed with 5 replicates per treatment and for one year. The analysis of carbon dioxide emission was done by one way ANOVA and Duncan's test. The results showed that the rate of carbon emission in Cupressus arizonica, Celtise caucasica and rangeland treatments was 110.49, 104.92 and 91.22 kg/ha/month, respectively and rate of carbon dioxide emission was 406.78, 384.71 and 48.433 kg/ha/month, respectively. The rate of carbon and carbon dioxide emission in 12 months in the area under consideration was also significant at 5% error level, have been with the highest carbon and carbon dioxide emissions in October and the lowest in August. In terms of seasonal distribution, the rate of carbon and carbon dioxide emission in rangeland and Cupressus arizonica treatments was not significant, but in the Celtise caucasica treatment was significant at 5% error level, with the highest carbon and carbon dioxide emission was in autumn, spring, winter and summer, respectively. In total, C.arizonica and C.caucasica reduced about 5/5% and 18% carbon and carbon dioxide emissions, respectively, than the adjacent rangeland did. Therefore, we can reduce the rate of carbon emission by appropriate management plans such as proper land use change.
Hamed Eskandari Damaneh; Gholamreza Zehtabian; Ali Salajegheh; Mehdi Ghorbani; Hassan Khosravi
Abstract
In this study, the effect of land use changes on groundwater resources as well as monitoring of spatial and temporal changes of groundwater quantitative and qualitative parameters were assessed in west basin of Jazmoryan Wetland. Landsat satellite images of TM 2002 and OLI 2015 sensors by applying of ...
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In this study, the effect of land use changes on groundwater resources as well as monitoring of spatial and temporal changes of groundwater quantitative and qualitative parameters were assessed in west basin of Jazmoryan Wetland. Landsat satellite images of TM 2002 and OLI 2015 sensors by applying of Maximum Likelihood Method were used to investigate land use changes trend. Also, information related to wells in years of 2002 to 2015 was used to assess groundwater quantitative and qualitative parameters. To do this, zoning maps of spatial and temporal changes of groundwater quantitative and qualitative parameters were prepared using the best interpolation method in ArcGIS software. The results related to evaluation of the best interpolation method showed that Kriging method had the least error. According to the results of this study, the area of agricultural and urban land uses has been increased, while the area of ephemeral stream, dam, rangelands, bare and mountain land uses has been decreased in 1394 compared to 1381.These changes indicate the increased degradation as well as unstable conditions of the region that adversely affect groundwater resources. As a result of these changes, groundwater quality in southern parts of the study area has been declined. Among the factor causing this declined groundwater quality are construction of Jiroft dam on Halil-rood permanent river, lack of water right and expanded urban and agricultural lands which have caused decrease in groundwater quality over time.
ayoub moradi; Ali Nakafinejad; Majid Ownagh; Choghi Bairam Komaki; mehrangiz foladi mansouri
Abstract
Indiscriminate land utilization methods, forest and rangeland degradation, land abandonment and development of residential areas contribute to the changes in flow intensity, erosion rate and sedimentation. Therefore, having knowledge on the effect of land use changes on discharge flow and sediment yield ...
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Indiscriminate land utilization methods, forest and rangeland degradation, land abandonment and development of residential areas contribute to the changes in flow intensity, erosion rate and sedimentation. Therefore, having knowledge on the effect of land use changes on discharge flow and sediment yield has been found necessary. The present research aims at investigating the effects of these factors by means of the semi-distributed Soil and Water Assessment Tool (SWAT) in Galikesh watershed, Golestan province (as a tributary of the River Gorganroud), in an area covering approximately 39000 hectares. This model was used in a 27-year period for simulation, calibration, validation and optimization of the parameters affecting flow and sediment yield. Land-use maps were prepared form the Landsat imageries dated 1987, 2000 and 2013. The SUFI2 model was used for model calibration and validation. Nash-Sutcliffe (NS) index was used as the objective function during model calibration (1990-2007) for the simulation of discharge and suspended load, which resulted in 0.63 and 0.61 that could be interpreted as satisfactory compared to the standards set in previous research. To evaluate the effect of land use changes on runoff and sediment yield, all model inputs, other than land use, were assumed constant. The results demonstrated that land use changes since 1987 to 2013 have led to an increase in annual runoff height by 1.40 mm and annual sediment concentration by 2 t.ha-1.
Kamran Karimi; Gholamreza Zehtabian; Marzban Faramarzi; Hassan Khosravi
Abstract
Remote sensing is a key technology for assessing expansion and rate of land cover changes that awareness of these changes as the basic information has a special importance for various programs. In this study, land use changes were examined over the past 24 years, and the feasibility of predicting ...
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Remote sensing is a key technology for assessing expansion and rate of land cover changes that awareness of these changes as the basic information has a special importance for various programs. In this study, land use changes were examined over the past 24 years, and the feasibility of predicting it in the future was evaluated by using the Markov chain model of the Abbas Plain. Landsat TM, ETM+, and OLI satellite images for the years 1968, 2003 and 2013, respectively; along with topographic and vegetation maps of the study region were used in this research. The images for three periods were classified into five land-use classes of rangeland, agricultural land (irrigated and rain-fed)), residential land, riverbed and barren and hilly land. According to the results, agricultural land is the most dynamic land-use class in the study area and its area has followed an upward trend during the period 1968 – 2003, so that 4337 ha (7.12%) has been added to this land-use class during this period. The trend of rangeland use change has had a descending trend during the period 1968 – 2003, so that has caused its area to be decreased by 3.19% (6573.6 ha) during this period. The results obtained from Markov chain analysis in the period 1968-2003, for model calibration; the maps for the years 1968 and 2003, and its matrix for predicating land use changes of the year 2023 indicate the Kappa coefficient equal to 80 percent. Based on the obtained results, in the year 2023, 49.1 and 10.1 percent of the study region are comprised of agricultural land and rangeland, respectively.
