Original paper

Environmental information management and hydrological system modelling for the assessment of hydrological eco system functions and services (ESF/ESS) in the Okavango River Basin

Helmschrot, J.

Abstract

Water is a key natural resource and required for a variety of ecosystem functions (ESF) and services (ESS). In semi-arid environments in Sub-Saharan Africa, where drinking water supply, livestock production, agriculture, wildlife, biodiversity and eco-tourism strongly depend on the natural water availability and its adequate quality, water related ESF and ESS as well as their interrelations are fundamental constituents of human wellbeing. Climate-driven but also socio-economic changes such as population growth, water take-off, deforestation, bush encroachment, the construction of reservoirs and increased water demand for irrigation are expected to affect the hydrological system dynamics of the Okavango River and its tributaries. Thus, the Okavango River Basin is considered a source of potential conflicts resulting from competing demands within and between the riparian countries in the near future. Addressing this development, a research study was initiated as part of the interdisciplinary, BMBF-funded project ‘The Future Okavango (TFO)’ in order to enhance the understanding of scale-related interactions between land management, climate conditions and hydrological ESF/ESS. The project develops suitable and robust methods and tools for the design and integrated assessment of land management options and climate change impacts on hydrological ESF/ESS at local, regional and trans-regional level in the Okavango River Basin. This will be achieved by applying a multi-scale approach based on comprehensive hydrological system analysis and modelling, integrating studies done at the micro/field scale and the meso/subcatchment scale with reference to the basin scale. A second aim of the presented research project is to develop an integrated, webbased Okavango Basin Information System (OBIS). A first version of OBIS is already implemented and provides a platform which allows authorized users to maintain, visualize and analyse geo-spatial data together with time series and information received from the interdisciplinary research efforts within TFO. This paper gives an overview of the current status of the multi-scale hydrological system analysis, data availability and constraints, the model concept and the implementation and population of OBIS. In addition, first hydrological assessments and modelling results are presented.

Keywords

Okavango RiverOBIShydrological assessmentESS/ESFOkavango Delta