Impacts of progressive deforestation
Introduction
Here we use Costing Nature (v. 2.46) and its land use change model to look for thresholds in biodiversity and ecosystem service loss on progressive deforestation in an area comprising lowland and montane environments in Peru, Ecuador, Colombia and Brazil. The deforestation scenario uses recent rates to project forward a progressive forest loss and replacement with cropland. The scenario applied was:
This leads to the following timeline of forest cover change from baseline,50,150 and 200 years:
Tree cover change
baseline
50
150
200
Results
*(all tabulated values are mean for the study area)
All variables decrease in a mildly non-linear way according with the geographical variation of the variable in question compared with the areas converted. Tree cover declines by 13%, carbon stock by 3.6%, water pollution increases by 14% (with initial increases the most significant). The potential bundled ecosystem services index declines as one might expect but the realised ecosystem, services index actually increases slightly on conversion. This is explained by the fact that conversion brings more agriculture and associated infrastructure meaning that realised hazard mitigation services from the remaining forests increase. Species richness declines more or less linearly reflecting the smooth distribution of species ranges in this area in comparison with the pattern of deforestation and the fact that v 2.46 does not account for the effect of edges on species loss (or carbon loss).
