Threat of water hyacinth (Eichhornia crassipes) on socio-economic and environmental sustainability of Koka and Ziway lakes, Ethiopia

Abstract

Invasive alien plant species cause severe socio-economic and environmental damage. In particular, the water hyacinth (Eichhornia crassipes) is an aggressive alien aquatic macrophyte that affects the socio-hydrologic and social environment in many parts of the globe. This study assessed the socio-economic and ecological impacts of the water hyacinth (WH) in Koka and Ziway Lakes in Ethiopia and recommends novel management practices. Purposive sampling design method was used to select households using systematic random sampling. The household sample size was determined with 95% confidence level. Data were collected through key informant interviews, focus group discussion and household surveys, prepared using the Kobo Toolbox which monitors data collectors online. A total of 413 households were sampled and the data were analysed through descriptive statistics and the ANOVA statistical package. At Lake Koka districts that the WH has caused 51% food insecurity by reducing food productivity, and 98.5% health distress through exposure to vector disease. At Lake Ziway districts it caused 81.6% food insecurity and 99.5% health distress. At both lakes, the WH affected the fishing industry by almost 100%. In terms of crop production, maize was significantly affected at Koka, 2 (1, = 413) = 117.01, p<.001 and cabbage was significantly affected at Ziway, 2 (1, N= 413) =6.36, p<.001. There was a statistically significant difference in annual income level, age of the household leader, and cost of recovery at household family size, F (9, 623.18) =14.38, p<.001; Wilks {Lambda}=.632, partial {eta}2=.14. Therefore, 195 (99.5%) households at Lake Koka and 215 (99.1%) at Lake Ziway illustrated the need for intervention to reduce health impacts and food insecurity. Despite the negative impact, at Lake Koka districts, 86.7% of the plant is used as cattle feed and 28.1% as fertilizer. At Lake Ziway, 42.9% of the plant is used as forage and 39.2%, as a fertilizer.