Watershed Management at ICRAF
Despite substantial research, many misconceptions exist about the relationships between trees and water in landscapes. Not only are there communication gaps between scientists and policy makers; there also are marked differences among scientists, including scientists with equally impressive backgrounds in forestry, hydrology or plant physiology. The World Agroforestry Centre (ICRAF) seeks to improve the empirical evidence, tools and overall scientific basis of watershed management, particularly on the potential of trees on farm to shape hydrologic processes.Tropical Deforestation, People and Floods
A misconception that keeps recurring in science and policy debates is that deforestation is the major cause of floods. For example a paper that Bradshaw et al (2007) recently published in the journal Global Change Biology presents evidence of a cross-country statistical relationship between deforestation and flood risk. Writing in the journal Nature, Laurance (2007) lauded Bradshaw et al as a landmark study demonstrating the important role of forests in reducing flood risk in developing countries. Bruijnzeel et al. (2007) have prepared a short paper that questions the data, methods and results of Bradshaw et al. Bruijnzeel et al. (2007) provide an alternative explanation based on the same data: population growth, which is correlated with deforestation, increases the likelihood of a flood being reported and increases the likely damage caused by floods that do occur. A 2005 paper by FAO and CIFOR challenges the conventional wisdom that reforestation and forest protection are the main solutions to floods, arguing instead that countries should instead focus on holistic watershed and river-basin management.
Read more on Tropical Deforestation, People and Floods
Synthesis Publications
At the 2006 Stockholm World Water Week, ICRAF launched 'The Difference a Tree Can Make' campaign, aimed at the synthesis and dissemination of past and current research results pertaining to tree-water-soil interactions.
- Synthesis 1 Tree Water Use
The right tree for a dry place
Authors: Rachel Rumley and Chin Ong
Certain trees that are integrated into agricultural systems can increase the efficiency of water use, while plantations of fast-growing trees can exacerbate water shortages. - Synthesis 2 Muddy Rivers
Muddy rivers — lack of trees?
Authors: Meine van Noordwijk, Bruno Verbist
and Kurniatun Hairiah
By clarifying the processes driving erosion and sedimentation, recent research in Indonesia is uncovering the roles of trees - outside forests - in protecting soils. - Synthesis 3 Science - Policy Nexus
Rooting policy in science
Authors: Brent Swallow and Rachel Rumley
More than 10 years of research supports the assertion that watershed policies can be developed and implemented on the basis of sound evidence that is relevant to the local context. - More Trees with Less Water
More trees with less water
Authors: Rachel Rumley, Catherine Muthuri
and Chin Ong
Farmers in semi-arid and arid regions can effectively manage the trade-offs between trees and water for both economic gain and environmental sustainability.
Research Projects
The World Agroforestry Centre (ICRAF) has more than two decades experience in researching watershed management issues in the tropics. Our current focus is on refining watershed management principles for different spatial scales (eg. plot-, field- and landscape level) and contexts (for example, agricultural land, natural and/or regenerated forests). ICRAF scientists are also developing models to predict the effects of different landscape configurations and identify best-bet management practices. In July 1999, ICRAF and the Kenyan Ministry of Agriculture and Rural Development (MoARD) initiated TransVic, a collaborative project aimed at providing extension workers, policy makers and researchers with information, methods, technologies and approaches for improving land productivity while enhancing local and regional environments in the Lake Victoria Basin.