The evaluation of modified productivity index method on the transitional volcanic-tropical landscape

Abstract

Soil erosion may accelerate the impact of climate change by releasing carbon, productivity loss, and harm the food production securities. Losing of soil productivity may lead to another land and forest clearing to support the agriculture activities. The Modified Productivity Index (MPI) is a new method to assess the effects of soil erosion on soil productivity. This research aimed to evaluate the application of MPI on the tropical volcanic landscape in Indonesia. It is important because having a good quantitative judgment on land evaluations will have a great impact to reduce climate change due to land mismanagement. The research area was at Bompon Watershed, Magelang Regency, Central Java, Indonesia. The method used MPI to estimate the soil productivity potency. The parameters observed were clay content, soil organic matter, soil pH, soil available water, and soil weight. The results found that PI was considered low, despite the actual condition of Bompon watershed which densely covered by vegetation. Turns out, there are some limitations of the method that needs to be corrected before widely applied in the tropical and multi-vegetation area such as Indonesia.