Human-related landscape; Quality indicator; Soil quality; South Kivu; Wetland degradation; Degradation indicators; Environmental stress; Quality indicators; Soil degradation; Soils qualities; South kivu; Water drainage; Wetland soils; Wetlands degradation; Decision Sciences (all); Ecology, Evolution, Behavior and Systematics; Ecology
Abstract :
[en] Due to environmental stress and anthropogenic pressures, wetlands are declining and being degraded in areas with increased settlement and road construction. Although various indicators have been developed to assess ecosystem degradation, few studies have specifically addressed wetland soil degradation and its underlying drivers. In this study, we attempted to create a Wetland Soil Degradation indicator (WSDI) and identify its driving factors in a contrasting landscape characterized by significant anthropogenic changes. We selected the eastern Democratic Republic of Congo (DRC), a region where severe wetland degradation primarily caused by agriculture and brickmaking activities has been reported. We combined Geographic Information System (GIS), remote sensing approaches and soil profile analysis. For landscape change, four concentric circles from the two wetland centers were made. A WSDI was developed and refined using the minimum data set (MDS) coupled with multivariate statistical techniques to assess the level of wetland degradation. For the case study, an overall WSDI score averaged 0.52 across the two sites. Higher degradation was observed in brickmaking (0.62) compared to agriculture zones (0.52), while intact zones had a lower score (0.28). Degradation was also more severe in completely drained areas (0.72) than in partially (0.48) and intact, non-drained areas (0.28). Significant correlations were found between the level of degradation and human-related landscapes, notably the proximity to villages, rural settlements, and roads. Wetland degradation was strongly linked to road accessibility and the distance to human-related landscapes. The indicator confirmed a gradual degradation pattern, starting from the wetland edges and moving toward the center. Overall, the WSDI is essential for diagnostic purposes before developing a restoration plan to ensure sustainability and to question these critical ecosystems’ future.
Research Center/Unit :
Laplec SPHERES - ULiège Lepur : Centre de Recherche sur la Ville, le Territoire et le Milieu rural - ULiège
Chuma Basimine, Géant ; Université de Liège - ULiège > Sphères ; Université de Liège - ULiège > Département de géographie > Service de géographie rurale (Laboratoire pour l'analyse des lieux, des paysages et des campagnes européennes LAPLEC)
Gustave, Mushagalusa N.; Faculty of Agriculture and Environmental Sciences, Université Evangélique en Afrique, Bukavu, Democratic Republic Congo
Schmitz, Serge ; Université de Liège - ULiège > Département de géographie > Service de géographie rurale (Laboratoire pour l'analyse des lieux, des paysages et des campagnes européennes LAPLEC)
Language :
English
Title :
Developing an indicator for assessing wetland degradation based on soil quality, water drainage, and human-related landscape factors
Publication date :
October 2025
Journal title :
Ecological Indicators
ISSN :
1470-160X
eISSN :
1872-7034
Publisher :
Elsevier
Volume :
179
Pages :
113987
Peer reviewed :
Peer Reviewed verified by ORBi
Development Goals :
6. Clean water and sanitation 1. No poverty 11. Sustainable cities and communities 14. Life below water
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