The Effect of Different Land Use Management Scenarios on Soil Erosion in Givi Chay Watershed
Document Type : Original Article
Authors
1
mProfessor of Geomorphology, Department of Physical Geography, Faculty of Social Sciences, University of Mohaghegh Ardabili, Ardabil, Iran
2
Professor, Department of Physical Geography, Faculty of Social Science, University of Mohaghegh Ardabili, Ardabil, Iran.
3
PHD student, Geomorphology, University of Mohaghegh Ardabili, Ardabil, Iran.
4
AssociateProfessor, Department of Watershed Managemant Faculty, University of Mohaghegh Ardabili, Ardabil, Iran.
10.22034/gmpj.2025.482427.1525
Abstract
Introduction
Soil erosion is a global problem that seriously threatens water and soil resources. It takes over 300 years to form just one centimeter of soil (Tripani, 2001). Therefore, preventing soil erosion is vital for preserving valuable natural wealth (Morgan, 1986). Soil erosion and sediment production cause numerous environmental problems. These sediments also lead to the entry of heavy metals, nutrients, and pesticides into river channels, affecting communities in various ways. Erosion and sediment production are complex functions of various factors, including geology, climate, topography, vegetation cover, and human activities. Soil erosion is a natural physical process through which soil particles detach from their original bed and are transported to another location by an agent of transport. Since millions of years ago, particularly when humans began manipulating ecosystems, the process of erosion has intensified and turned into an environmental hazard (Esmaeili & Abdollahi, 2011).
Methodology
The study area encompasses the Givi Chai river basin, approximately 44 kilometers long, which is one of the permanent rivers in Ardabil province. The geographical coordinates of this region are as follows: - Longitude: 48° 4' 58" to 48° 40' - Latitude: 37° 57' 48" This area is located in zone 38 and features diverse land uses, including agriculture, pasture, and forest
Data Collection Necessary data, including climatic information, soil characteristics, and types of land use, were collected from local sources and weather stations Considering the diversity of land use and the possibility of reducing erosion by using cover management and conservation agriculture methods, a scenario-based approach was used to compile possible land use scenarios. In the following, based on the conditions of the studied area and also the land use situation, in addition to the existing situation scenario, six other scenarios were compiled with the aim of improving the factor of plant management and soil protection against erosion. The amount of soil erosion in each of the scenarios was determined using the G2 model and the amount of erosion was calculated in each land use and in each management scenario. After preparing the map of erosion factors in the G2 model, the soil erosion map of the study area was prepared in the GIS environment. Considering the diversity of land use and the possibility of reducing erosion using cover management methods and conservation agriculture, a scenario-based approach was used to compile possible land use scenarios. In the following, the amount of soil erosion with cell dimensions of 20 x 20 meters was compiled in each of the scenarios.
Data Analysis Data analysis was conducted using GIS software and the G2 model to identify vulnerable areas. Results The results indicated that different land uses have varying impacts on soil erosion rates. Specifically, agricultural lands experienced the highest levels of erosion, while forested areas exhibited the least erosion. Impact of Land Use Changes in land use can significantly affect soil erosion. Improper management of agricultural lands and overgrazing can lead to increased erosion. Strategies To reduce soil erosion, it is recommended to adopt sustainable agricultural practices and restore forested areasConclusion This study demonstrated that the G2 model is an effective tool for assessing soil erosion in the Givi Chai region. The results obtained can aid in management planning for soil health preservation and erosion reduction. Implementing sustainable land use management measures is essential to prevent further erosion.
Results and Discussion
The results indicated that different land uses have varying impacts on soil erosion rates. Specifically, agricultural lands experienced the highest levels of erosion, while forested areas exhibited the least erosion. Impact of Land Use Changes in land use can significantly affect soil erosion. Improper management of agricultural lands and overgrazing can lead to increased erosion. Management Strategies To reduce soil erosion, it is recommended to adopt sustainable agricultural practices and restore forested areas. Based on the scenario map of the existing situation, the values of soil erosion are between zero and 70 tons per hectare. Most of the erosion is observed in agricultural lands. Based on the obtained results, the lowest amount of erosion reduction is related to dense and medium vegetation, which is presented in the form of a scenario. By analyzing the effects of the scenario in reducing erosion, it can be concluded that if it is possible to restore medium and poor pastures and turn them into good pastures according to the conditions of the region, a significant amount of soil erosion can be reduced.
Conclusion
Soil erosion using the G2 model in Givi Chai watershed shows that this model is specifically designed to evaluate and predict soil erosion and sedimentation. The erosion values were estimated in the existing situation and six management scenarios, and the analyzed results were mentioned below, some general results that may be obtained from this model. Examining the soil erosion map shows that its average amount is 3.3 tons. Using the G2 model and combined parameters, the soil erosion rate is calculated. This step includes the use of special formulas of the G2 model, which gives weight to different factors. After calculating the erosion rate, prepare the final soil erosion map in the ArcGist environment, and this map should include high, medium and low erosion risk areas. As a result, by preparing a land use map, the amount of erosion was determined for all uses, and the results of erosion in each of the uses show that the amount of erosion has increased in most of the uses. But the highest amount of erosion and sedimentation is residential areas and agricultural land respectively. The general conclusion is that the type of land use directly affects the amount of sedimentation and improper management can lead to soil erosion and pollution of water resources. It is possible to reduce the amount of significantly reduced soil erosion and basically the combined scenario provides better results. In this regard, it is suggested that urban and agricultural planning be done in a way that uses sustainable methods, such as maintaining vegetation, using conservation agriculture techniques, and designing infrastructure to control runoff.
Soil erosion is a global problem that seriously threatens water and soil resources. It takes over 300 years to form just one centimeter of soil (Tripani, 2001). Therefore, preventing soil erosion is vital for preserving valuable natural wealth (Morgan, 1986). Soil erosion and sediment production cause numerous environmental problems. These sediments also lead to the entry of heavy metals, nutrients, and pesticides into river channels, affecting communities in various ways. Erosion and sediment production are complex functions of various factors, including geology, climate, topography, vegetation cover, and human activities. Soil erosion is a natural physical process through which soil particles detach from their original bed and are transported to another location by an agent of transport. Since millions of years ago, particularly when humans began manipulating ecosystems, the process of erosion has intensified and turned into an environmental hazard (Esmaeili & Abdollahi, 2011).
Methodology
The study area encompasses the Givi Chai river basin, approximately 44 kilometers long, which is one of the permanent rivers in Ardabil province. The geographical coordinates of this region are as follows: - Longitude: 48° 4' 58" to 48° 40' - Latitude: 37° 57' 48" This area is located in zone 38 and features diverse land uses, including agriculture, pasture, and forest
Data Collection Necessary data, including climatic information, soil characteristics, and types of land use, were collected from local sources and weather stations Considering the diversity of land use and the possibility of reducing erosion by using cover management and conservation agriculture methods, a scenario-based approach was used to compile possible land use scenarios. In the following, based on the conditions of the studied area and also the land use situation, in addition to the existing situation scenario, six other scenarios were compiled with the aim of improving the factor of plant management and soil protection against erosion. The amount of soil erosion in each of the scenarios was determined using the G2 model and the amount of erosion was calculated in each land use and in each management scenario. After preparing the map of erosion factors in the G2 model, the soil erosion map of the study area was prepared in the GIS environment. Considering the diversity of land use and the possibility of reducing erosion using cover management methods and conservation agriculture, a scenario-based approach was used to compile possible land use scenarios. In the following, the amount of soil erosion with cell dimensions of 20 x 20 meters was compiled in each of the scenarios.
Data Analysis Data analysis was conducted using GIS software and the G2 model to identify vulnerable areas. Results The results indicated that different land uses have varying impacts on soil erosion rates. Specifically, agricultural lands experienced the highest levels of erosion, while forested areas exhibited the least erosion. Impact of Land Use Changes in land use can significantly affect soil erosion. Improper management of agricultural lands and overgrazing can lead to increased erosion. Strategies To reduce soil erosion, it is recommended to adopt sustainable agricultural practices and restore forested areasConclusion This study demonstrated that the G2 model is an effective tool for assessing soil erosion in the Givi Chai region. The results obtained can aid in management planning for soil health preservation and erosion reduction. Implementing sustainable land use management measures is essential to prevent further erosion.
Results and Discussion
The results indicated that different land uses have varying impacts on soil erosion rates. Specifically, agricultural lands experienced the highest levels of erosion, while forested areas exhibited the least erosion. Impact of Land Use Changes in land use can significantly affect soil erosion. Improper management of agricultural lands and overgrazing can lead to increased erosion. Management Strategies To reduce soil erosion, it is recommended to adopt sustainable agricultural practices and restore forested areas. Based on the scenario map of the existing situation, the values of soil erosion are between zero and 70 tons per hectare. Most of the erosion is observed in agricultural lands. Based on the obtained results, the lowest amount of erosion reduction is related to dense and medium vegetation, which is presented in the form of a scenario. By analyzing the effects of the scenario in reducing erosion, it can be concluded that if it is possible to restore medium and poor pastures and turn them into good pastures according to the conditions of the region, a significant amount of soil erosion can be reduced.
Conclusion
Soil erosion using the G2 model in Givi Chai watershed shows that this model is specifically designed to evaluate and predict soil erosion and sedimentation. The erosion values were estimated in the existing situation and six management scenarios, and the analyzed results were mentioned below, some general results that may be obtained from this model. Examining the soil erosion map shows that its average amount is 3.3 tons. Using the G2 model and combined parameters, the soil erosion rate is calculated. This step includes the use of special formulas of the G2 model, which gives weight to different factors. After calculating the erosion rate, prepare the final soil erosion map in the ArcGist environment, and this map should include high, medium and low erosion risk areas. As a result, by preparing a land use map, the amount of erosion was determined for all uses, and the results of erosion in each of the uses show that the amount of erosion has increased in most of the uses. But the highest amount of erosion and sedimentation is residential areas and agricultural land respectively. The general conclusion is that the type of land use directly affects the amount of sedimentation and improper management can lead to soil erosion and pollution of water resources. It is possible to reduce the amount of significantly reduced soil erosion and basically the combined scenario provides better results. In this regard, it is suggested that urban and agricultural planning be done in a way that uses sustainable methods, such as maintaining vegetation, using conservation agriculture techniques, and designing infrastructure to control runoff.
Keywords
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