Sub-Watershed Prioritization for Erosion Susceptibility based On Drainage Morphometric Characters

This study finds 1D, 2D and 3D morphometric parameters of the middle-west part of Kushtia district, Bangladesh to implement groundwater potential. For this purpose, the SRTM (DEM) data were used to compute different parameters in GIS environment. The values of 1D parameters like stream order, stream length and mean bifurcation ratio was calculated as 6, 1774.72 km and 2.08 respectively. The computed values of drainage density (0.01 - 23.06 km/km2), stream frequency (1 - 5.64 per km2), drainage texture (0.25 - 0.70 km/km4), length of overland flow (0.02 - 45.05 km2/km), constant of channel maintenance (0.04 - 90.04 km2/km), circularity ratio (0.39 - 0.84), form factor (0.35), elongation ratio (0.62), relief ratio (0.00 - 1.81) and ruggedness number (0.04 - 214.72) disclose the morphometrical conditions of the study area. The results revealed from this study on drainage morphometry can be a great assistance for understanding the hydro-geomorphological character of the area.

The Tabuk province of Saudi Arabia (SA) has an arid zone, few aquifers, high groundwater salinity (seawater intrusion), and accelerated population, industrial, and agricultural development. The development of Tabuk Basin is essential for the addition of new freshwater resources and the enhancement of aquifer recharge potential. The hydrological characteristics of the drainage basin aid in the identification of watersheds, enabling the protection and management of land erosion and ground/surface water resources. This study analyzed hydro-morphometric data from the eighteen sub-basins of the Tabuk Basin using multivariate statistical approaches and coupled remote sensing (RS) and geographic information systems (GIS) for water priority determination. The results show that the four principal components(PC1-4) have a variance of90.4% concerningbifurcation ratio (Rb), ruggedness number (Rn), elongation ratio (Re), drainage density (Dd), basin relief (Bh), circularity ratio (Rc), and relief ratio (Rh). The Al Ula, Thaibah, Hamd, Dama, Al Wajh, Al Ghamra, and Azlam sub-basins showed the highest priority, indicating soil erosion and the necessity for mitigating measures to reduce infrastructure damage. Mostexposed geology (67%) exhibited strong permeability and good infiltration (sedimentary cover and Quaternary sediments). The rest(23%) showed low to medium permeability(igneous, metamorphic, and carbonate rocks). The bestpromisingsitesfor building new wells can reduce surface runoff and soil erosion through aquifer infiltration and abstraction. The aquifer potentiality map was accomplished for Al Ula, Thaibah, Hamd, and Dama drainage basins. The most prospective groundwater investigation regions were identified, coincidingwith the drilled wells that confirmed and validated the results. The estimated zones of high to very high aquifer potentiality were used to add additional wells for investment reduce soil erosion, mitigate alternatives, agriculture,urbanization, etc. The other sub-basins have a medium to low priority, with less soil erosion and aquifer recharge.

Soil wearing away or erosion is a chief agent of land loss in agricultural land and is regarded worldwide as a serious environmental hazard. This study performed watershed prioritization using morphometric parameters based on fuzzy best worse method (F-BWM) and GIS integration for Gusru Watershed, India. This study prioritizes sub-watersheds of the study area from viewpoint of soil erosion using five major parameters i.e., stream frequency (Fs), relative relief (Rr), length of overland flow (Lo), relief ratio (Rh) and drainage density (Dd). Fuzzy based Best Worse Multi-Criteria Decision-Making (F-BWM) Method was used to assigning weights to used criteria and combining them to achieve erosion susceptibility for each sub-watershed. Results showed that sub-watersheds 9, 14, and 5 were most susceptible to soil erosion and sub-watershed 3 was the least from the viewpoint of soil erosion ranking.

Investigating the geomorphological and hydrological characteristics of a watershed is essential for determining and predicting erosion potential, controlling runoff, and developing conservation strategies for land and water resources. However, such quantitative assessments were limited in the Gelda Sub-watershed. The objective of this study was to assess the morphometric characteristics of the entire Gelda Sub-Watershed, enabling the prediction of erosion potential and the identification of priorities for implementing conservation practices. For delineating the 26 sub-watershed and compute the significant morphometric parameters that directly related the hydrological and erosional response of the watershed counting bifurcation ratio, drainage density, basin relief, relief ratio, dissection index, ruggedness number, infiltration number length of over land flow and stream frequency a 12.5 m by 12.5 m resolution Digital Elevation Model (DEM) and ArcGIS 10.7 were used. For prioritizing the most vulnerable sub-watersheds via erosion, and suggesting appropriate erosion management strategies, the Composite Parameter Factor (CPF) value was employed. The results indicate that sub-watersheds, including WS-19, WS-23, WS-20, WS-22, WS-25, and WS-26, with CPF values ranging from 8.00 to 9.44, were highly vulnerable to erosion and classified as very high-priority areas requiring immediate conservation measures. High-priority areas such as WS-14, WS-2, WS-16, and WS-10 necessity appropriate intervention, whereas Medium and low-priority sub-watersheds accounting for 33.75% of the study area require moderate maintenance-level measures. Overall, 57.98% of the sub-watershed falls within very high and high priority classes, which need abrupt soil and water conservation measures like terracing, check dams, afforestation, and land-use regulation. The finding may contribute to practical applications in targeted and cost-effective soil and water preservation measures, support sustainable watershed management, boost agricultural production, and strengthen landscape resilience against degradation. Moreover, it reveals that the combined technique of morphometric analysis, combined with field verification, offers a strong and reproducible framework for sub-watershed prioritization. This approach facilitates efficient watershed management and can be extended to other Ethiopian basins and other similar landscapes to assist erosion control, enhance groundwater recharge, and encourage sustainable terrestrial management. Clinical trial number: The manuscript titled Geomorphological Analysis of Sub-Watershed for Enhancing Hydrological Assessment and Sustainable Watershed Management: A Case Study of Gelda Watershed, Tana Sub-Basin, Ethiopia, does not include a Clinical Trial Number.

Identification of the sensitive regions to soil erosion can be the foremost step in controlling the vigorous pace of soil degradation in agricultural lands. This study employs individual and ensemble models including compound factor (CF), analytical hierarchy process (AHP), and technique for order preference by similarity to ideal solution-analytical hierarchy process (TOPSIS-AHP) for identifying the regions susceptible to soil erosion in Dnyanganga watershed of India using morphometric attributes (MAs). Thirteen MAs were computed using the newly released TanDEM-X data, which is a bi-static X-band interferometric Synthetic Aperture Radar (SAR) acquisition. Weights for each of the MAs were calculated using AHP, which was employed in both AHP and TOPSIS-AHP models. The outcome of the AHP model displays that watershed slope (Sw), stream frequency (Fu), ruggedness number (Rn), and relative relief (Rr) greatly influences soil erosion in the study area. The priority ranking outcome of individual and ensemble models are compared using the Spearman correlation coefficient test (SCCT) and Kendall tau correlation coefficient test (KTCCT) to select the best model for soil erosion susceptibility mapping. The result of the non-parametric tests reveals that TOPSIS-AHP ensemble model is better in ranking alternatives than the individual models. According to TOPSIS-AHP ensemble model, the sub-watershed DNY16 is highly susceptibility to erosion, whereas DNY1 is least susceptible. Based on the ensemble model, 14.54%, 41.02%, and 44.43% of the area in Dnyanganga watershed fall under high, medium and low soil erosion susceptible classes, respectively. The results from this study will aid decision makers in better conservation planning of soil and water resources.

Global increase in demand of water resources stepped up due to climate change and increase in population, stimulates an efficient development, management and conservation of water resources by quantifying the available water within the catchment to bridge the gap between its demand and availability. Initiated at a watershed scale, it is important to quantitatively evaluate the geomorphological parameters, since all the hydrologic and geomorphic processes may be accounted and balanced within a watershed. This study presents an excellent morphometric characterization of Payppara and Tikovil sub watersheds of Meenachil basin, in the state of Kerala, India, evaluated using SRTM DEM at 30m×30m spatial resolution as input to QGIS. The important linear morphometric aspects like stream order, length of stream segments, bifurcation ratio, Rho coefficient, the areal morphometric aspects like form factor, drainage density, stream frequency, elongation ratio, length of overland flow and relief aspects like ruggedness number, watershed relief were calculated for a comprehensive understanding of the geomorphic characteristics of the watershed. The general terrain of Tikovil was found to be steep but it was relatively mild for Payppara. The gravity flow paths traced by few 4th order, 3rd order and 2nd order stream segments of Payppara were identified as potential groundwater recharge zones. The derived morphometric characteristics benefits a better understanding of the formation of erosive and permeable surface flow paths in response to precipitation, the principal input to the hydrological budget.

Morphometric parameters are important indicators to understand the hydrological and morphological behavior of river basin. In this study, GIS and remote sensing techniques were effectively used to analyze the morphometric parameters including linear, geometric, basin texture (aerial) and relief aspects of the Kal River Basin in the Raigad district, Maharashtra, India. The work outlines the significance of digital elevation model (SRTM 30m acquired from the USGS Earth Explorer) for assessment of drainage pattern and extraction of relative parameters by using QGIS 3.18 software. The findings of the study categorize Kal River Basin as a 5th order drainage basin based on Strahler order with a total area of 272.64 km². The linear aspects, stream length ratio, bifurcation ratio, and rho coefficient indicated that presence of mountain environment and plateau, dendritic drainage pattern and higher hydrologic storage during floods within the basin. In areal aspects, drainage density (1.18 km/km2), stream frequency (1.03 km2), circulatory ratio (0.19), form factor (0.38), length of overland flow (0.42) and sinuosity index (1.57) implied that area having coarse drainage texture, permeable sub-soil materials, low density of streams, highly elongated shape, younger stage of basin, high length of overland flow during intensive rainfall with more channel erosion and moderate runoff potential and the basin has meandering topology. Further the relief parameters depict geo-morphologically mature stages of the basin development, presence of rolling and gentle slopes in the basin, having complex structures of an erosion prone landscape. These findings underscore the necessity of adopting targeted soil and water conservation measures, promoting vegetation cover restoration, and implementing sustainable watershed management strategies to ensure the long-term hydrological and ecological stability of the Kal River Basin. appropriate measure structure locations for preventing the soil from getting eroded from the study area.

16 - Prioritization of Flood Inundation of Maharloo Watershed in Iran Using Morphometric Parameters Analysis and TOPSIS MCDM Model

In the present study, soil erosion prioritization of sub-watersheds of the Kulfo River basin was conducted by adopting a drainage morphometric analysis along with a statistical correlation matrix-based weighted sum approach. The drainage network extracted and sub-watershed boundaries were demarcated through GIS techniques using advanced space-borne thermal emission and reflection–digital elevation model (ASTER–DEM). The Kulfo River basin was separated into six sub-watersheds (SW-1 to SW-6), and different morphometric criteria were calculated using the standard formula. And, morphometric parameters like drainage frequency, bifurcation ratio, drainage density, form factor, circulatory ratio, drainage texture, elongation ratio, compact coefficient, and length of overland flow have been considered for sub-watershed prioritization. Based on the results, the Kulfo River basin’s sub-watersheds were categorized into five priority classes: very low, low, medium, high, and very high. The results illustrate the sub-watersheds (SW-1, SW-2, SW-3, and SW-6) that approximately 65% of the Kulfo River basin’s total area fall under the very high, high, and medium soil erosion-prone areas, respectively. Therefore, the above-mentioned four sub-watersheds can be a value for the consideration of the soil protection plan. The outcomes derived from this study will be valuable information for several partners like agriculturists, surface and groundwater wealth administrators, and decision-makers for improving the soil management process. The current research shows that ASTER–DEM data, GIS approach, and a statistical correlation matrix-based weighted sum approach are vibrant tools for watershed prioritization in data-scarce regions.

Watershed prioritization involves the identification of critical areas that are vulnerable to soil erosion and produce higher sediment yield. These areas need conservation activities on a priority basis. The soil erosion and subsequent yield from different watershed areas depend on multiple factors, so the selection of watershed based on a single factor may have the potential risk of wrong selection. The multi-criteria decision support-based analytical hierarchical process can be used conveniently for prioritization of watershed, where erosion process relies on various interdependent and spatially distributed factors. For prioritization, Bhopal Lake catchment was divided into twentyfour sub-watersheds (SW-1 to SW-24) and ten erosion hazard parameters (EHPs) were analysed for all sub-watersheds, which were used as inputs in a decision support system for the identification of erosion-prone areas. Based on susceptibility to erosion and sediment yield, the sub-watersheds were classified into five priority categories: very high, high, medium, low, and very low for the conservation and management of subwatersheds. The sub-watersheds SW-19 and SW-24 have been characterized as a very high erosion area covering about 26 km2 area, which is 7% of the total study area where immediate implementation for soil and water conservation (SWC) measures are required.

An integrated statistical-geospatial approach for the delineation of flood-vulnerable sub-basins and identification of suitable areas for flood shelters in a tropical river basin, Kerala

A systematic review of soil erosion in citrus orchards worldwide

Soil erosion is a major environmental problem that threatens world food production; it can be described as the removal of organic as well as inorganic soil surface materials by wind and water. This (e present) study aims to identify the most erosion vulnerable sub-watersheds for planning appropriate conservation intervention and restoration measures in Jedeb watershed. Revised Universal Soil Loss Equation (RUSLE) integrated with satellite remote sensing (RS) and geographical information system (GIS) has been applied to calculate potential soil loss at sub-watershed level. The parameters of RUSLE model were estimated using remote sensing data and ArcGIS software. The rainfall erosivity R-factor was found from 3209.6 to 3896.69 MJ.mm/ (ha.h), soil erodibility K-factor varies from 0.1 to 0.25 t ha h/ (ha MJ mm), Topographic (LS factor) ranging from 0.19 to 6.7, C-factor varies 0.01 to 0.25 and support practice P-factors from 0.1 to 1. The total annual soil loss potential of the study area was found 1,383,158 t/ yr from the total watershed area of 29,633 ha. Average annual soil loss at sub-watersheds level was estimated from 29.275 to72.529 t/ha/year and mean annual soil loss of the entire watershed was 46t/ha/year. The study results indicated that potential soil erosion rate in the watershed was ranged into four priority categories from high to extremely severe. Three sub-watersheds covering 22.975% of the watershed shows very severe mean soil loss rate, two sub-watersheds was found severe mean soil rate which covered 19.014%, eight sub-watershed were existed under very high mean soil loss rate covers 47.59% and Three sub-watersheds were found in the high soil loss rate and covers 10.42%. Sever and extremely severe micro watersheds demand immediate attention in terms of management and planning perspective. Soil and water conservation structure was recommended and designed based on peak runoff rate, soil type, slope of the land, land use type and soil erosion hazard . Keywords : Soil Erosion; RUSLE; GIS; Soil Conservation; Jedeb watershed; Ethiopia DOI: 10.7176/JNSR/10-9-02 Publication date: May 31 st 2020

Geo-visualization concept has been used for positioning water harvesting structures in Varekhadi watershed consisting of 26 mini watersheds, falling in Lower Tapi Basin (LTB), Surat district, Gujarat state. For prioritization of the mini watersheds, morphometric analysis was utilized by using the linear parameters such as bifurcation ratio (Rb), drainage density (Dd), stream frequency (Fu), texture ratio (T), length of overland flow (Lo) and the shape parameter such as form factor (Rf), shape factor (Bs), elongation ratio (Re), compactness constant (Cc) and circularity ratio (Rc). The different prioritization ranks were assigned after evaluation of the compound factor. 3 Dimensional (3D) Elevation Model (DEM) from Shuttle Radar Topography Mission (SRTM) and DEM from topo contour were analyzed in ArcScene 9.1 and the fly tool was utilized for the Geo-visualization of Varekhadi mini watersheds as per the priority ranks. Combining this with soil map and slope map, the best feasibility of positioning check dams in mini-watershed no. 1, 5 and 24 has been proposed, after validation of the sites.

An investigation of morphometric parameter for the Umtung River basin, situated in Meghalaya, India, employing advanced GIS and remotely sensed data. Various morphometric parameters were quantified, including basin area (224.91 km²), length (24.32 km), perimeter (147.04 km), and drainage density (1.34 km/km²). With 255 streams overall, the research showed a clearly defined stream order system up to the fifth order. Key findings indicate that the basin exhibits low stream frequency (1.13 stream/km²) and a bifurcation ratio (Rb) averaging 4.03, suggesting a complex, interconnected hydrological system with significant tributary contributions. The sinuosity index (SI) of 1.32 indicates a moderately sinuous channel morphology. An extended basin shape that is advantageous for flood management is suggested by a low form factor (0.38) and elongation ratio (0.39). With a ruggedness number (Rn) of 1.18, a relief ratio (Rr) of 35.85, and a basin relief of 872 m, relief metrics show notable topographical diversity driven by tectonic activity and differential erosion. Hypsometric analysis indicates a mature landscape characterized by concave slopes, underscoring the erosion-dominated landforms formed over geological time.