Influence of land use/cover change on provisioning and regulating ecosystem services in a papyrus wetland in the Lake Victoria Basin in Kenya
SUPERVISOR: Thomas HEIN
PROJECT ASSIGNED TO: Risper Ajwang' ONDIEK
Papyrus wetlands in the Lake Victoria basin provide a wide range of ecosystem services (ESS) that support livelihoods. However, the wetlands are steadily converted to agriculture. In the Kenyan part of the basin, studies have reported area loss in some papyrus wetlands of up to 50% in the last four decades. At the household level, the drivers of wetland conversion to agriculture are unclear. Also, the land use/cover change is likely to influence provisioning (crop production and artisanal papyrus products) and regulating (greenhouse gas emissions and water purification) ESS but are hardly investigated. Therefore, using the Anyiko wetland in the Kenya part of the basin as a case study, this study (i) analysed socio-economic determinants of land use/cover change in the wetland, (ii) assessed the influence of land/cover change and season on methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) emissions, and (iii) assessed the relationships between the provisioning and water purification ESS. The results showed that households were more likely to cultivate the wetland if they did not harvest papyrus for artisanal products, were male-headed and lacked alternative sources of income. The perceptions on the wetland value did not influence its cultivation. The conversion of the wetland areas to farmland resulted in CH4 uptake irrespective of the season and high N2O emissions during the dry season. CO2 emissions did not vary significantly between the land-use types. Lastly, there were trade-offs between crop production and nutrient retention and positive synergies between artisanal papyrus products and nutrient retention. Converting the entire wetland to agriculture would increase crop production and diminish nutrient retention and artisanal papyrus products. The findings of this study are important in supporting sound decision making on sustainable utilisation of the papyrus wetlands for livelihoods enhancement in the basin.