Spatial analysis of deforestation in Indonesia in the period 1950–2017 and the role of protected areas

Indonesia is one of the countries with highest forest loss rates in the world. Protected areas (PAs) can have a key role in counteracting deforestation, especially if they are combined with the active involvement of local communities, rather than be only based on strict nature conservation. The study aims at assessing and measuring forest transformations in 1950-2017 through GIS-based spatial analyses, and to evaluate the role of PAs in preserving forests from deforestation. At national level forests dramatically decreased, passing from 78.3% of the total surface in 1950, to 63.8% in 1982 and to 46.8% in 2017. In the period 1950-2017, 35% of the national territory (over 66 million of hectares) has been affected by deforestation at an average rate of 985,200 ha/year; the areas where deforestation proceeded at higher rates are Sumatra (356,100 ha/year) and Kalimantan (303,360 ha/year). Deforestation occurred with higher intensity at lower altitudes and along the coast, due to the spread of modern plantations. The only exception is represented by Java and Bali as most of deforestation already occurred before 1950. PAs demonstrated to be effective in slowing down deforestation rates, but not in stopping it as deforestation is also affecting PAs. The study provided reliable spatial data on forest transformations in the last 67 years, highlighting differences related to geographical zone and altimetry, allowing the identification of the most vulnerable PAs. The amount of data produced at national and regional level could support further studies aimed at recognizing the best strategies to counteract deforestation, contributing to sustainable forests management and to forest preservation.