Evaluating land use change trajectories following forest loss in Indonesia
Abstract
Indonesia has lost a significant portion of its primary forests over the last several decades, and slowing forest loss is an important component of the country's Nationally Determined Contributions for reducing carbon emissions. However, efforts to prevent deforestation in Indonesia are complicated by a lack of consensus regarding the extent to which various drivers contribute to the clearing of intact and degraded natural forests. Here, we address existing uncertainty relating to the relative contributions of deforestation drivers in Indonesia using a sample-based approach. A set of 10,000 30x30 meter sample pixels were selected from throughout the archipelago using a simple random sampling design and subsequently evaluated by experts using Landsat composite images covering a 32-year period as reference data. We found that Indonesia lost an estimated 25.21 (+/- 0.64) Mha of primary forest from 1991-2016. Approximately 27% of this area was converted to oil palm during the study period, including 3.68 (+/- 0.26) Mha of land directly converted from primary forest to oil palm, and another 0.93 (+/- 0.13) Mha planted with oil palm within 5 years of primary forest clearing. Smallholder land use (not for monoculture oil palm) was another significant driver for forest loss. In 2016, smallholder land, including both actively cultivated agricultural plots and fallows at various stages of regrowth, covered an estimated 17% of the area cleared after 1990, of which 3.95 (+/- 0.27) Mha was directly converted from primary forest for smallholder use. However, while oil palm and smallholder agriculture represented the two most significant productive land uses in previously forested areas, the majority (52%) of forest cleared in Indonesia was left unused immediately after clearing, including 15% of land cleared by fire and 37% left unproductive for one or more years following non-fire clearing. Much of this area (68%) was never converted to any productive use, and land that was eventually converted was often left unused for years. Policies designed to reduce deforestation in Indonesia must include strategies to address this phenomenon, such as by preventing clearing for speculation and land banking, in addition to addressing more conventional drivers, such as the direct conversion of forests for large- and small-scale agriculture.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.B14B..03P
- Keywords:
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- 0439 Ecosystems;
- structure and dynamics;
- BIOGEOSCIENCESDE: 0480 Remote sensing;
- BIOGEOSCIENCESDE: 1632 Land cover change;
- GLOBAL CHANGEDE: 1807 Climate impacts;
- HYDROLOGY