http://ir.bdu.edu.et/handle/123456789/17112 2001-01-01T06:17:19Z 2001-01-01T06:17:19Z Mohammed, Ibrahim http://ir.bdu.edu.et/handle/123456789/17329 2026-09-04T08:26:56Z 2022-08-01T00:00:00Z

Ecological Condition, Ecosystem Services and Economic Valuation of Wetlands in the Lake Tana Sub-Basin, Ethiopia Mohammed, Ibrahim In the Lake Tana Sub-basin, wetlands play a significant role in providing multiple services. However, the local people have continued exploiting these resources with little interest to protect them. The resources have also attracted less attention in national and regional planning. As a result, they have started to show signs of degradation. So, to minimize further degradation and understand the current status of wetland health, frequent monitoring is required. Therefore, this study was conducted from October 2019 to August 2021 to determine the ecological status, ecosystem services, economic values and land cover changes of Shesher, Chimba, Avaji, Yitamot, Dena and Wonjeta wetlands. Household (HH) interviews using semi-structured questionnaires, field observations and focus-group discussions were used to collect primary data. The market price, replacement cost, contingent valuation and the reference methods were employed to estimate the monetary values of ecosystem services. Macroinvertebrate-based metrics and human disturbance score indices were used to determine water quality status and ecological conditions. In addition, Landsat data of 1986, 2000, 2010 and 2020 were used to determine land cover changes and predictions and land cover maps were developed using ArcGIS, and IDRISI software. Ecosystem service and water quality related data were analyzed using SPSS, PAST and MS-Excel software. The results revealed that the extent of wetland reduction during the last 34 years was 372.67 km 2 of area, while further reduction by 189.32 km 2 is expected in 2050. Regarding the ecological status, Shesher Wetland was severely impaired by human activities (HDS=89), followed by Avaji (HDS=84) and Chimba (HDS=76). Despite the poor ecological status, households benefited from wetlands through the provision of food, water, medicinal plants and raw materials. Concerning the status of ecosystem services, 55.17% of the provisioning, 10.34% regulating, 6.89% cultural and 10.34% supporting services were perceived as vulnerable. Regarding service predictions, 6.8% would remain stable, 41.37% will slightly decrease, 41.37% will decrease and 10.34% have a slightly increasing tendency in the future. Monetary wise, the six wetlands provide services that total 105,191,384.1 USD/yr to the country’s economy. Specifically, wetlands contributed 63,636.56 USD/HH/yr, 5,303.04 USD/HH/month and 976.61 USD per capita/month to the livelihoods of the local people. The study also indicated that a multimetric index composed of %EOT (Percentages of Ephemeroptera, Odonata and Trichoptera), %Diptera, %Filterers, EPT/C (The ratio of Ephemeroptera, Plecoptera and Trichoptera to Chironomid), biomonitoring working party score and Shannon diversity index discriminated between the disturbance groups and could be used to assess water quality. Economic problems, absence of policy, lack of awareness and socio-demographic factors were capable of influencing the participation of HHs in wetland disturbance. In conclusion, wetlands in the Lake Tana Sub-basin are still playing a significant role in the livelihoods of the community although they have shown increasing degradation. Therefore, to minimize further deterioration, concerned authorities should recognize the monetary value of ecosystem services, take appropriate measures to address the identified causes of disturbances, and invest in longterm management of the wetlands.

2022-08-01T00:00:00Z