Dynamics of Benguet pine (Pinus kesiya Royle ex Gordon) and broadleaved forests in relation to highland vegetable ecosystem in Ampusongan Watershed Benguet, Philippines

System analysis enables sound understanding of the connectivity of the processes and functions associated with the problem of the landscape and component over time. This study focused on understanding the dynamics among three major ecosytems namely: Benguet pine forest (pine), broadleaved forest (broadleaved) and vegetable farms in the Ampusongan Watershed. The rate of forest degradation and landscape structure pattern from 2002 to 2014 was determined. Moreover, underlying drivers of forest degradation associated to farming and assessed forests' plant diversity, landscape functionality and soil physico-chemical properties as influenced by patch size and elevation was also determined. Forest lost vegetable farm was almost 6-times higher in the pine that broadleaved ecosysems. Forest fragmentation due to vegetable farming was higher in pine that the latter. Socio-cultural, economic, political/governance, technological and natural factors aggravate farming and forest degradation. Plant diversity in both forests was influenced more by elevation than by patch size. Diversity index was higher in broadleaved especially in tree community having several dominating tree species as compared to only one, Pinus kesiya, in pine. Plant species occurred in broadleaved was more than twice in pine, with only few species common to both. Broadleaved had higher total soil surface assessment functionality than pine in some patches due to higher infiltration and nutrient cycling indices in several patches. Soils in broadleaved were more acidic, higher in organic matter and phosphorus than in pine at mid elevation. Variation on biophysical-chemical properties were attributed to feedback effects of trees, fire influence and landscape heterogeneity. Vegetable farms and roads have profound influence on the rate and pattern of forest degradation and that various drivers influencing farming and ecological functions of forests should be considered for effective forest conservation and sustainable vegetable production.