Mapping the extent and climate impacts of land use change in Indonesia, 2000-2020
Tracking twenty years of forest loss
Indonesia’s vast expansion of agricultural land-use in the 21st century has caused a notable decline in the country’s forest cover. This has amounted to a loss of 97,000 km2, or 8.1%. Under its current ambitious drive to tackle food security, this trend is set to intensify.
Analysis by the LEAF Indonesia team reveals an unprecedentedly detailed picture of the environmental consequences of these changes in the years 2000-2020, with close-up analyses of our three focus provinces: Gorontalo, East Kalimantan and West Papua.
Indonesia, 2000
The deforestation of this period has had clear costs for the
carbon storage, biodiversity and climate resilience of the
landscape, all integral to sustainable food production. Our
analysis of the data for the country in these years on the
University of Sussex’s Landscape Integrative Mapping and Modelling for Multifunctional Analysis (LIMMMA) platform offers an evolving way to reliably measure the impacts of future interventions. This can be achieved on LIMMMA in a high level of visual detail and across a range of scales, from local to national, anywhere in the world.
There is now an urgent need for Indonesian land-use decision-making to be grounded in a robust and data-driven “what-if” understanding of the environmental trade-offs.
Forests: direct and indirect exploitation for agriculture
Using LIMMMA, we have gained a greater understanding of the extent and character of forest decline across Indonesia in 2000-2020. By modelling ‘established forest’ as areas with a canopy height of 10m or more from a combination of satellite imagery and other remote-sensing data, LIMMMA distinguishes these areas from those of less dense woodland or vegetation.
Gorontalo, 2000
East Kalimantan, 2000
From this, we can see that exploitation of Indonesia’s
forests in this period was driven by agricultural
development through a combination of direct clearance
and gradual encroachment. Sometimes the latter has
preceded the former, with Gorontalo being more a case of
gradual encroachment while East Kalimantan witnessing more direct clearance. We can also see that while agricultural development has been the key driver of deforestation in 2000-2020, direct clearance has been primarily driven by large-scale oil palm and pulpwood plantations, as well as logging. Food crop production, meanwhile, has increased steadily in this period, and especially in the 2010s, but primarily through gradual encroachment of forest land rather than direct clearance. This may change, however, if gradual encroachment becomes less feasible in future.
Forest canopy volume, the average height per unit of land, can be a reliable indicator of an area’s carbon storage, biodiversity and climate resilience. It can then be used to model how these will trade off with a given land use change in that area.
Biodiversity
Biodiversity in Indonesia has generally declined between 2000-2020, and this has been consistently reflected across our three focus provinces with the most severe cases precisely in those areas where forests have been most exploited. Across the country
generally, as well as in
Gorontalo, East Kalimantan and
West Papua, rice and other crop
production has been linked with
the areas of lowest biodiversity
measured by the
Commonwealth Scientific and
Industrial Research
Organisation’s Biodiversity
Habitat Index.
The case of West Papua suggests that biodiversity loss may be an early-warning sign of other less immediately apparent types of environmental degradation.
Climate resilience
The past decade has witnessed a steady uptick in reports of flooding, fires and landslides in areas where agricultural exploitation has been most intense. While possibly reflecting an increase in reporting, the geographical link with areas of deforestation and agricultural land-use is clear. While we don’t yet have measurements of the social and economic impacts of these changes, the adverse consequences of a less climate-resilient landscape have clear costs for Indonesia’s economy and population.
Next steps
Our latest research provides an unprecedentedly clear picture, enabled by the LIMMMA platform, of the impacts of recent land-use change in Indonesia. It also highlights the vital role that key habitats play for sustainable food production by maintaining carbon storage, biodiversity and climate resilience:
1) Established forests act as carbon sinks and biodiversity reserves
2) Future large-scale clearance of forests should be subject to “what-if” modelling
3) Degraded forest land should be recognised and conserved as a “critical transition zone”
4) “Suitable land” for agricultural development should be determined by robust systems
Our evolving, open-source approach means that we can and will continue to further refine our models in LIMMMA with new and available third-party data. Besides integrating more detailed datasets from crop types to socioeconomic metrics, we aim to develop our models into a direct “what if” system for users to model multiple impacts of land use changes.
Read our full report.
Carbon storage
Using average forest canopy height as a guide, we estimate how the exploitation of Indonesian forests in 2000-2020 notably reduced estimated carbon storage capacity of the landscape.
However, there have been areas of preservation, for example in Gorontalo, where losses have been partly offset by the carbon sink of intact forests continuing to grow naturally. This highlights the importance of forest conservation to carbon storage levels.
