Soil erosion and environmental degradation due to the cultivation of marginal upland areas are now considered major environmental risks in the Philippines. Agroforestry may help address the situation. In agroforestry systems, the positive interactions of tree-crop combinations not only improve biophysical conditions in farms, but also enhance food security in farming households.A combination of Participatory Rural Appraisal (PRA), a household survey, focus group discussions, fi eld experiments, and simulation modeling was undertaken in Claveria, Misamis Oriental, Philippines. The agroforestry system adopted depended on the farmers' motivations. The adoption of agroforestry signifi cantly increased the households' level of income by around 42-137 %, compared with that from continuous annual mono-cropping. Another benefi cial feature of an agroforestry system was the enhanced nutrient infl ow to the system through leaf litterfall, stemfl ow, and throughfall. A modeling study using the WaNuLCAS model showed that the Eucalyptus -maize hedgerow system provided signifi cant improvements to a range of biophysical and economic measures of productivity and sustainability.It is recommended that both national and local government units mainstream their policies and efforts toward promoting agroforestry adoption in the Philippine uplands.
Keywords
IntroductionThe uplands in the Philippines are of great importance and interest because they comprise about 59 % of the country's total land area. They are dynamic and highly interactive landscape components of the rural system, and also serve as the life support for the lowlands and coastal areas. In addition, they are home to the increasing population of the "poorest of the poor," and are expected to absorb more of the expanding population (Sajise and Ganapin 1991 ).The Philippine uplands are a very heterogeneous and fragile resource base (Sajise and Ganapin 1991 ). Most of these areas are either open grassland, degraded, or occupied by settlers (Villancio et al. 2003 ). More than 20 million people are estimated to have settled in the uplands, and the number is increasing at a rate of about 2.8 % annually, which is above the national average of 2.32 %.Its geographical location has made the Philippines highly vulnerable to natural hazards, the most common of which is the occurrence of turbulent typhoons. During the decade from 2001 to 2012, the country was hit by a total of 184 typhoons, or an average of 18 typhoons per year (Israel and Briones 2012 ). Climate change is perceived to have increased the frequency and intensity of heavy rainfall associated with typhoons and other weather systems, resulting in fl ooding. From 2000 to 2010, damage to agricultural crops caused by typhoons, fl oods, and droughts amounted to nearly PHP 106.88 million. Rice, corn, and other high value cash crops sustained the most damage. Typhoons Ondoy (Ketsana) and Pepeng (Parma) in September and October 2009 wrought havoc in both urban and rural areas in the country, with total damage reachin...