Biodiversity-related ecosystem service provision in managed landscapes
Sudanian savannas comprise a vast mosaic of near-natural savanna and woodland habitats of widely differing size, utilized savannas, and converted and cultivated areas, the latter replacing original ecosystems rich in woody species with a diverse fauna. The woody vegetation and its associated fauna provide direct Ecosystem Services (ESS) for all daily needs, and indirect but eminently important ESS pertaining to soil conditioning by nutrient enrichment, aeration and rain water retention, sequestering of carbon, prevention of erosion, and purification of water and air. These ESS are the basis for continued regeneration of natural biodiversity allowing for continued use of the many vital natural goods and services. The degree of intactness of ESS determines the degree of resilience of savannas towards ecological changes such as climate shifts. A further crucial ESS is thus the capability of species-rich savannas to mitigate the effects of climate changes.
The presence of key savanna species and the proper takeover of their functional role usually require their integration into near-natural communities and a mosaic of such communities within a diverse landscape. It is mandatory to integrate such habitats into the cultivation system. Their spatial arrangement is crucial for the entire ecological functioning. It must sufficiently allow for intactness and connectivity of natural habitats and neighbourhood relations toward land use areas. Application of related socio-ecological indicators on landscape metrics and savanna ESF in a trade-off analysis on reinforcing savanna resilience shall constitute an innovative landscape approach for developing future management for optimized resilience and ESS provision of savannas with particular reference to hydrological, soil and general vegetation cover characteristics in the habitat matrix.
The core research questions are:
- Which key factors and processes ensure long-term pollination and recruitment of woody species to reliably and optimally provide the relevant ESS of animal and plant communities under different climate change scenarios?
- What are their spatial trade-offs in the landscape matrix?
- Which cultural and socio-economic conditions and rules prevented an excessive use of useful species and ecosystem processes in former times?
Field data on biodiversity patterns and ecological processes as well as ethnobotanical and ethnozoological data from interviews shall be analyzed at the local population level, serving as baseline data for characterizing ESF and as ground truthing data. Remote sensing data on landscape metrics for joint analysis with other GIS layers shall be treated at the ecosystem level, integrating the population-level data into the spatial system of the landscape matrix and thus establishing the innovative functional approach.