Anthropogenic threats to wetland resources and its implication on carbon sequestration in Southwestern Ethiopia

Abstract

Even though wetlands have been valued for their numerous ecosystem services and hydrological, ecological and habitat functions, its services have been threatened by its sudden losses. Nevertheless, the losses along its driving factors and the effects brought due to the loss have not been scientifically investigated. The study is geared to scrutinize anthropogenic threats to wetland and its implication on carbon sequestration in southwestern Ethiopia. A combination of geospatial and socioeconomic data were utilized to attain the intended objectives. A total of 384 households were selected using simple random sampling technique from sample kebeles to assess the drivers of wetland degradation. Besides, to address the experimental work, the wetland was stratified, and soil samples were taken from three classes of wetlands viz., permanent wetlands (intact wetlands), semi disturbed wetlands and wetlands converted to agricultural land. From the total category of wetlands, 24 composite soil samples in five replications at a depth of 0-20 cm were collected. The result of Landsat imageries revealed that Wichi wetland area has been shrinking. It was 17.4% of the area in 2001, while it declined into 3.1% in 2021. There is a significant difference (p < 0.05) in soil Organic Content in between different classes of wetlands. The organic carbon content of soils converted to agricultural land is very low. In intact/undisturbed wetlands, there is better carbon content than other states of wetlands. This triggers the wetlands to lack their pristine nature. To reverse these problems, integrated problem-solving approach through collaboration of stakeholders from policy level down to grassroots community is found to be essential for sustainable wetland management in the area.