Conservation trade-offs and land use change projections for northern Borneo
Co$ting Nature 2.43 was used to examine the top 12% priority areas on the basis of biodiversity, ecosystem services, threat and delphic conservation priority for northern Borneo
Baseline ecosystem services
Realised ecosystem services (on a scale of 0-1 globally) in western Zambia including nature based tourism, carbon sequestration and storage, water provision (Relative volume of clean (not human impacted) water available to downstream people and dams) and hazard mitigation (Relative hazard mitigation services for flood/drought, landslide/erosion, inundation/tsunami/cyclone according to relative risk protected against) are highly spatially variable as is the distribution of threatened biodiversity (Relative richness and endemism for redlisted mammals, reptiles, amphibians, birds).
Current pressure (Current pressure according to population, wildfire frequency, grazing intensity, agricultural intensity, dam density, infrastructure (dams,mines,oil and gas, urban) density) on ecosystems is also highly spatially variable as is future threat (Future threat according to accessibility, proximity to recent deforestation (MODIS), projected change in population and GDP, projected climate change, current distribution of nighttime lights).
Current conservation prioritisation schemes (Conservation priority by overlap of EBAs (Birdlife), Global200 Ecoregions (WWF), Hotspots (CI), Last of the Wild (WCS,CIESIN), Important Bird Areas (Birdlife) and Key Biodiversity areas (IUCN, BI, PI,CI)) show a complex pattern of priorities focused on the heart of Borneo but the Co$ting Nature Relative aggregate nature conservation priority index (realised services) (Pressured and threatened conservation priority areas with high realised service provision) shows priorities also in other locations.
Deforestation over the last 10 years has occurred over upto 11% of the study area with a further 7% converted to plantations. Deforestation affected some 2900 of the 40900 units (7.1%) of Relative total realised bundled services index (ie realised services) and some 13000 out of 193000 (6.7%) of potential ecosystem services.
The top 12% of areas for the bundle of realised ecosystem services (Total realised services including water, carbon, nature based tourism and hazard mitigation services) is different to the top 12% for biodiversity (Relative richness and endemism for redlisted mammals, reptiles, amphibians, birds), delphic conservation priority (Conservation priority by overlap of EBAs (Birdlife), Global200 Ecoregions (WWF), Hotspots (CI), Last of the Wild (WCS,CIESIN), Important Bird Areas (Birdlife) and Key Biodiversity areas (IUCN, BI, PI,CI)) and on the basis of threat (Future threat according to accessibility, proximity to recent deforestation (MODIS), projected change in population and GDP, projected climate change, current distribution of nighttime lights).
Trade-offs therefore need to be made to protect the most important areas on multiple metrics
Projecting land use change and impacts into the future
Recent deforestation rates were projected for a further 100 years (with little attention to forest degradation) and assigned according to proximity to existing deforestation, accessibility and likely future road developments. Protected areas were considered to be robust and thus no deforestation in existing protected areas was permitted.
The resulting changes in forest cover (especially high in Indonesia) were used to better understand impacts on biodiversity and ecosystem services Bundled ecosystem services decrease in the deforested areas and also affect areas downstream and could lead to losses of 51 million tonnes of carbon storage and 34000 tonnes of carbon sequestration per year. The populations of on average 50 and upto 180 red-listed amphibians, reptiles, mammals and birds would be affected.
A further scenario was run in which land use change was permitted also inside protected areas. Deforestation rates are so high in Borneo that the resulting level of deforestation removes almost all remaining forest within 100 years (except in Brunei) and leads to a catastrophic drop in the bundle of ecosystem services throughout the area and in biodiversity, especially in the north west.