Spatial Analysis of Sediment Connectivity and Its Role in Water and Soil Resource Management (Case Study: Manjanigh Watershed, Khuzestan)
Authors
1
Assistant Professor, Department of Soil Conservation and Watershed Management Research, Khuzestan Agricultural and Natural Resource Research Center, Agricultural Research, Education and Extension Organization, Ahwaz, Iran.
2
Assistant Professor, Department of Soil Conservation and Watershed Management Research, Khuzestan Agricultural and Natural Resource Research Center, Agricultural Research, Education and Extension Organization, Khuzestan , Iran.
3
Assistant Professor, Forests and Rangelands Research Department, Khuzestan Agricultural and Natural Resources Research and Education Center, Agricultural Research Education and Extension Organization, AREEO, Ahvaz, Iran
10.22034/wmji.2025.2064664.1119
Abstract
Identifying and mapping areas with a high potential for sediment transfer is one of the key challenges in sustainable watershed management, particularly in mountainous and semi-arid regions. In this study, the Sediment Connectivity Index was employed as a quantitative, spatial, and efficient tool to analyze sediment transfer dynamics in the Manjanigh watershed, Khuzestan Province, Iran. Using digital elevation model data and Sentinel-2 satellite imagery, the vegetation cover index was derived, and subsequently, the upstream and downstream components of the SCI were calculated within the Google Earth Engine (GEE) cloud-computing environment. Spatial distribution maps of SCI were then produced. The results indicated that areas with steep slopes and sparse vegetation cover (characterized by high vegetation index values) exhibited the highest SCI values, underscoring the controlling influence of these factors. Moreover, a strong positive correlation (r = 0.84) was found between SCI values and field-measured sediment yield data, confirming the high accuracy of the index in representing the actual potential for sediment transfer. The findings of this study not only enable precise and targeted identification of critical erosion and sediment-prone areas but also demonstrate the utility of SCI as a scientific tool for optimizing the spatial planning of watershed management interventions and enhancing participatory natural resource management in similar regions. Implementing this approach can significantly contribute to the development of effective regional programs aimed at reducing soil erosion, controlling sediment, and improving water quality.
Keywords
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