期刊名称：Journal of Environmental Hydrology (ältere Jahrgänge)
印刷版ISSN：1058-3912
电子版ISSN：1996-7918
出版年度：2010
卷号：18
出版社：IAEH
摘要：A study was conducted in the Calabarzon Region, Philippines, to determine the natural boundary and extent of watershed areas as well as the amount of run-off they can generate. Geospatial processes determined the natural boundary by following the highest ridge dividing each watershed and showed that the basin in this part of the region has a total area of around 93,000 ha and consists of three catchments/watersheds. The Kaliwa watershed occupies the largest area, 50.7% of the total, followed by Kanan watershed with 42.2%. The Agos river, the confluence of these two watersheds, flows down to the Polillo Strait and serves as the political boundary between the two municipalities. It has a catchment area of 7.1%. A curve number (CN) model showed the watersheds combined surface run-off is around 243 million cubic meters based on soil type, landcover and 30-year precipitation data. The Kaliwa watershed occupies the largest area and is capable of generating the highest surface run-off, followed by the Kanan watershed and Agos river catchment with 119 M, 108 M and 16 M cubic meters, respectively. The quality of soil and high precipitation results in a high amount of run-off. These findings are significant to the community living in and around the area and can be used by managers for decision and policy making.
