POLICY BRIEF SERIES | PBS 2014-2
by Rex Victor O. Cruz
Watersheds are a landscape of interconnected ecosystems, and it is in the abundance of ecosystems that watersheds derive its importance due to the vast array of ecosystem services that it provides to humanity.
A sustainable watershed is a resilient watershed. In a sustainable watershed, the mechanisms involved to sustain the ecosystems within it are working properly. These mechanisms include soil conservation, water conservation, biodiversity conservation, and climate change mitigation.
Humanity benefits from sustainable watersheds in many ways. A sustainable watershed minimizes flooding; enables water and power sufficiency; and provides vibrant business and industry, healthy population, and productive farmlands. All of these benefits translate to income and welfare gains for society. Ironically, it is also those who benefit from watersheds—the people—who contribute immensely to the degradation of watersheds.
Human and Natural Stressors
There are two kinds of stressors that put watersheds under stress: human stressors and natural or climate-induced stressors.
Human stressors are those impacts that are triggered by human activities, population increase, and other economic factors. Human activities that contribute to the degradation of watersheds include upland agriculture, land conversions, human-induced soil degradation, destructive mining, and illegal logging.
Furthermore, the increased demand for food and water, increase in population density in the river basin, and increase in poverty incidence resulting from population growth adversely affect watersheds. All of these impact on watersheds, as the resources that can be found in the watershed are used to service the increasing population.
Economic factors not only constrain opportunities for viable livelihood but also hinder watershed users from adopting conservation-effective technologies due to the costs that entail their usage. Examples of these economic factors are poor infrastructure and insufficient capital assets.
However, the fundamental causes of watershed degradation lie in watershed managers’ weak governance (Figure 1). Such weak governance is evident in poor planning and execution of land use and management plans; multiple and overlapping government agencies involved in watershed management; weak policies, enforcement, and monitoring; lack of capable actors and players; absence of adequate information; and undervaluation and under appreciation of watershed resources.
Meanwhile, natural or climate-induced stressors are manifested through higher evaporative demand; decrease in runoff to surface water supply; lower recharge into groundwater; extended drought and flood; saltwater intrusion and coastal flooding; and increased runoff, siltation, and urban runoff, among others. These manifestations may consequently lead to species becoming out of range. They may also result to alteration of species composition, distribution, and interactions; alteration of fruiting and flowering; pest and disease outbreak; species loss; alteration of ecosystem functions and services; and changes in the quality and area of forests and other critical habitats.
All in all, climate change may alter ecosystem functions and services. However, even without climate change, many watersheds in Southeast Asia are already compromised. As such, the threats posed by climate change could worsen the condition of damaged watersheds in the region.
Some Impelling Considerations in Watershed Management
There are certain issues that need to be considered to ensure that watersheds are managed effectively. These considerations serve as guiding principles when implementing interventions and mechanisms related to watershed management.
Since watershed management plays a key role in achieving development goals, efforts should be made to address the issues and challenges in watershed management. According to FAO (2007), nurturing watersheds is a collective responsibility. Watershed management thus requires the participation of all stakeholders—forest users, farmers, landholders, local government, and line agencies, among others.
1 Dr. Rex Victor O. Cruz is Professor at the College of Forestry and Natural Resources, University of the Philippines Los Baños.
FAO. 2007. Why invest in watershed management? Rome, Italy. Retrieved from http://www.fao.org/docrep/010/a1295e/a1295e00.htm