Integrated Modeling of Land and Water Resources in two African Catchments

Abstract

Although all care is taken to ensure integrity and the quality of this publication and the information herein, no responsibility is assumed by the publishers, the author nor UNESCO-IHE for any damage to the property or persons as a result of operation or use of this publication and/or the information contained herein. A pdf version of this work will be made available as Open Access via http://repository.tudelft.nl/ihe This version is licensed under the Creative Commons SUMMARYLand and water are two of the most important and interacting natural resources that are critical for human survival and development. Growing population and global economic expansion are accelerating the demand for land and water for uses such as agriculture, urbanization, irrigation, hydropower, and industrialization. The land surface changes dynamically due to these demands and other socio-economic drivers. Biophysical factors such as topographic suitability, climate change, and rainfall variability further influence landuse changes and land-use change decisions. Water resources are likewise experiencing pressure from overuse, pollution, and changes in hydrologic processes as a result of both socio-economic and biophysical factors.Land and water resources are considered to have strong interactions. Although the science of this interaction is not new, the two are typically managed under separate governance systems (Le Maitre et al., 2014). As a result, land-use change and hydrology or water resources are studied usually separately. Modelers and model developers reproduced the existing separation in governance of land and water resources in their respective models, which gave rise to mild treatment of one of the resources when analyzing the other. The result is that hydrology and water resources are often considered to be processes and resources affected only by biophysical components, ignoring anthropogenic contributions that may actually influence such characteristics through direct effects on land-use, for instance.The need to understand and explicitly represent the interaction between water resources on the one hand and land-use changes with its drivers on the other is imperative for sustainable management of integrated natural resources management in general and land and water resources management in particular. In recent years, interesting sub-disciplines such as 'socio-hydrology' are emerging which recognize and emphasize the importance of socioeconomic and anthropogenic effects on hydrologic and water resources analysis. Interaction and feedback between land-use and water resources is still not explicitly and dynamically represented in most scientific modeling tools related to land and water, however.Furthermore, often due to limitations of access and computing resources, frameworks for communicating integrated assessment and modeling in a way that can be operational to resource managers and decision makers related to such resources is limited. This is especially evident in developing regions. After the land-use models calibrated and...