Remote sensing-based monitoring of water hyacinth invasion dynamics and socioeconomic impacts in Lake Abaya, Ethiopia

Abstract

Water hyacinth, an invasive aquatic plant originally from the Amazon Basin, has posed a severe threat to the Lake Abaya ecosystem since 1990. This study utilized Sentinel-2A satellite imagery from 2017 to 2023 to analyse the spatiotemporal dynamics and socioeconomic impacts of water hyacinth on the lake. Employing a supervised image classification algorithm within a Quantum Geographic Information System (QGIS) environment, the research identified a steady increase in infestation during the first four years, followed by a slight decline over the final three years due to local intervention efforts. Crucially, the spatial analysis revealed that the lake's open water coverage decreased from 139,455.06 hectares to 116,094.91 hectares over the study period. This decreasing trend in the water surface area was directly linked to the invasion dynamics of the water hyacinth. Furthermore, socioeconomic assessments conducted via household surveys and focus group discussions confirmed that infestation disrupts ecological balance, degrades the environment, and reduces economic productivity of the lake ecosystem. The study concludes that the rapid expansion of farmland and settlements, coupled with the loss of critical water surface area, necessitates integrated restoration and catchment management strategies to mitigate the adverse impact of water hyacinth on both the local ecosystem and rural livelihoods of the study area.