Benefits from ecosystem services in Sahelian village landscapes
Focalimember Hanna Sinare defend her academic dissertation for the Degree of Doctor of Philosophy in Natural Resources Management at Stockholm University 11 November. Access the thesis here.
The defense takes place 11th of November at 10.00 in Vivi Täckholmsalen, NPQ-huset, Svante Arrhenius väg 20 at Stockholm University.
Opponent: Assistant Professor Berta Martín-López, Institute of Ethics and Transdisciplinary Sustainability Research, Leuphana University, Germany. Committee:Professor Anders Malmer, Department of Forest Ecology and Management & SLU Global, Swedish University of Agricultural Sciences. Adjunct professor Niina Käyhkö, Department of Geography and Geology, University of Turku, Finland. Docent Håkan Berg, Department of Physical Geography, Stockholm University.
Download the thesis hereRead more about Hanna Sinare here
Abstract:
Rural people in the Sahel derive multiple benefits from local ecosystem services on a daily basis. At the same time, a large proportion of the population lives in multidimensional poverty. The global sustainability challenge is thus manifested in its one extreme here, with a strong need to improve human well-being without degrading the landscapes that people depend on. To address this challenge, knowledge on how local people interact with their landscapes, and how this changes over time, must be improved. An ecosystem services approach, focusing on benefits to people from ecosystem processes, is useful in this context. However, methods for assessing ecosystem services that include local knowledge while addressing a scale relevant for development interventions are lacking.
In this thesis, such methods are developed to study Sahelian landscapes through an ecosystem services lens. The thesis is focused on village landscapes and is based on in-depth fieldwork in six villages in northern Burkina Faso. In these villages, participatory methods were used to identify social-ecological patches (landscape units that correspond with local descriptions of landscapes, characterized by a combination of land use, land cover and topography), the provisioning ecosystem services generated in each social-ecological patch, and the benefits from ecosystem services to livelihoods (Paper I). In Paper II, change in cover of social-ecological patches mapped on aerial photographs and satellite images from the period 1952-2016 was combined with population data and focus group discussions to evaluate change in generation of ecosystem services over time. In Paper III, up-scaling of the village scale assessment to provincial scale was done through the development of a classification method to identify social-ecological patches on medium-resolution satellite images. Paper IV addresses the whole Sudano-Sahelian climate zone of West Africa, to analyze woody vegetation as a key component for ecosystem services generation in the landscape. It is based on a systematic review of which provisioning and regulating ecosystem services are documented from trees and shrubs on agricultural lands in the region.
Social-ecological patches and associated sets of ecosystem services are very similar in all studied villages across the two regions. Most social-ecological patches generate multiple ecosystem services with multiple benefits, illustrating a multifunctional landscape (Paper I). The social-ecological patches and ecosystem services are confirmed at province level in both regions, and the dominant social-ecological patches can be mapped with high accuracy on medium-resolution satellite images (Paper III). The potential generation of cultivated crops has more or less kept up with population growth in the villages, while the potential for other ecosystem services, particularly firewood, has decreased per capita (Paper II). Trees and shrubs contribute with multiple ecosystem services, but their landscape effects, especially on regulating ecosystem services, must be better studied (Paper IV). The thesis provides new insights about the complex and multi-functional landscapes of rural Sahel, nuancing dominating narratives on environmental change in the region. It also provides new methods that include local knowledge in ecosystem services assessments, which can be up-scaled to scales relevant for development interventions, and used to analyze changes in ecosystem services over time.