SP1: Biodiversity and the supply of water-related NCPs

• Applicants: Professor Dr. Lutz Breuer; Professorin Dr. Suzanne Jacobs
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions ; Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 428658210

While SP1 focused on investigating the overall supply and regulation of Nature’s Contributions to People (NCP) on Mt. Kilimanjaro in Kili-SES-1, the second phase now focuses on water-related NCPs. In addition, the project will assess transformation using human-water system trajectories to investigate the effect of climate change, land use and management on the future supply and demand of water-related NCP, with a particular focus on the potential for riparian forest restoration. In the first phase, we developed a framework to quantify how NCP supply depends on interactions between NCP regulator and provider species. We also assessed tree-related habitats and the response of soil and aboveground carbon storage to both direct climate effects and those indirectly mediated by plant traits. A grab sampling campaign provided information on spatial patterns in water quality and their suitability for drinking and irrigation. We further established a soil moisture sensor network at 26 study plots, covering all 13 ecosystem types. These data were used to analyse plot-scale hydrological processes related to infiltration and preferential flow. Six discharge gauging stations in three catchments complemented our monitoring effort. SP1 will build on the latter work to address its first objective, to assess the regulation of water supply along climate and land use gradients (Work package WP1). Using data from the sensor network, we will develop tailor-made hydrological models using the Catchment Model Framework to simulate water dynamics from plot to catchment scale. Our second objective aims to disentangle the role of the surrounding landscapes in regulating water quality as well as linking terrestrial and aquatic biodiversity with stream integrity (WP2). To achieve this, we will assess various water quality parameters, macroinvertebrate diversity and leaf litter breakdown rates at sites with undisturbed, degraded, absent, and restored riparian zones in targeted sampling campaigns. Landscape analysis using random forest regression models will be applied to predict spatial variations in water quality and aquatic biodiversity. The third objective investigates human-water system trajectories to study the future of water-related NCP. Using the hydrological models from WP1, the spatial water quality models from WP2 and results obtained in Kili-SES-1, WP3 will project the supply of water-related NCP under different scenarios of climate change, land use and management as well as human preferences and demand. In summary, SP1 will provide crucial information on the current state and potential future of water-related NCP, which were underrepresented in previous research, but valued highly by many stakeholders in the social-ecological system, through a combination of high-resolution monitoring, sampling campaigns for water quality and aquatic biodiversity, and modelling approaches.

• DFG Programme: Research Units
• Subproject of: FOR 5064: The role of nature for human well-being in the Kilimanjaro Social-Ecological System (Kili-SES)
• International Connection: Tanzania
• Cooperation Partner: Dr. Grite Mwaijengo
• International Co-Applicant: Dr. Subira Munishi