National Research and Development Project for watershed management: Pagsanjan-Lumban Watershed, Laguna [Philippines]

The watershed plays a critical role in the sustenance of its surrounding environs. Its vast natural resources provide an array of protective services and amenities, educational and scientific opportunities, as well as psycho-physiological influences. Watershed also provide water for domestic, agricultural and ecological maintenance services. It also a have of several communities that depend greatly on the watershed for its livelihood. This project generated data and information through a network of Learning Watersheds that would be useful in guiding policy decisions on the kind and the extent to which various land uses and land use practices could be allowed in the watershed without impairing the sustainability of surface and ground water resources. This could also provide fresh information for a better understanding on the responsiveness of policies such as on the withdrawal of critical watersheds and watershed reservations from agriculture and other uses. Hence, founded in the vision of enhancing science and technology-based watershed and ecosystem management, the general objective of this project was to develop a network of learning watersheds and watershed management decision support system. Biophysical and geomorphic features of a watershed are helpful vulnerability indicators. Characterizing these features could provide information on the potential threats to a watershed, which the managers, planners, decision makers and researchers can use. The Pagsanjan-Lumban Watershed [Laguna, Philippines] has a relatively flat to moderately sloping to rolling topography starting from the lakeshore going towards the mountains. Its drainage density value is relatively high, which may be due to the presence of impermeable sub-surface material, sparse vegetation and high relief. The texture ratio of the watershed is also quite low and has a hydrologically long basin lag time.