WATERSHED MANAGEMENT
kaingin systems and their component management practices and to determine the future cultivation intensity within a given area. This should serve as the basis for determining whether upland farming systems using sustainable kaingin practices could form one component of an overall watershed management plan based on the concept of multiple use. Myth 4. Reforestation alone will solve the problem. Poor plantation establishment and management practices can result in higher losses than from well managed hillside farms. The extensive undergrowth and ground cover to be found within many of the traditional Philippine coconut based multi-storey farming systems means that such systems will often provide as good, if not better soil and water protection (as well as better economic returns) than commercial timber plantations. Fast growing exotic tree species have high water demands. The unintended effect of planting them for watershed protection purposes may be a reduction in total water yield, particularly when planted close to springs, reservoirs and along stream banks. Myth 5. Land under 18% slope is suitable for agriculture, land over 18% slope is not. The risk of erosion under agriculture is a combination of factors notably soil type, rainfall intensity, ground cover, slope length and steepness, and the type of land management practiced. There is thus no scientific basis for fixing the sage limit for agriculture solely on the 18% slope limit. Where the soils are deep, and resilient, annual crop cultivation can be practiced on slopes steeper than 18%, providing the appropriate conservation effective land management practices (e.g., contour tillage and vegetative strips, or terracing) are used. Crops have been grown on the Banaue terraces for centuries. Equally there are other soil types that are highly sensitive to mismanagement and even on slopes as gentle as 2-3% are subject to severe degradation if used for agriculture. Thus the safe limits for agriculture within watershed areas should be based on a full land suitability assessment not just an arbitrary slope limit. Myth 6. Watersheds are socio-economic and socio-political units. A watershed is a clearly recognizable natural hydrological unit. However it is not a socio-economic and socio-political unit as its hydrological boundaries rarely, if ever, coincide with the cultural, administrative and political
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S E RV I C E D E L I V E R Y W I T H I M P A C T: R E S O U R C E B O O K S F O R L O C A L G O V E R N M E N T