2007 period, whereas 17.6% of the forest below 1,000 m was lost during that period. Te main land use that replaced forest on mineral soil was agroforestry (31%), with oil palm being the second-largest land-use, replacing forest (19%). Overall, how- ever, 81% of forest loss on mineral soils was converted to land uses other than oil palm.
Te net present value land-use analyses indicate that for all land uses that replaced forest on mineral soils in the Leuser Ecosys- tem (except for oil palm), the net present value is lower than that of the value of avoided CO2
Deforestation on peat soil was driven almost exclusively by palm oil (79%). Te economic analysis shows that the value of avoided deforestation CO2
emissions from above and below ground car- emissions from deforestation.
In other words, 81% of the deforestation on mineral soils could probably have been avoided during the 1985-2007 period if a REDD mechanism had been in place.
bon is higher than that of all other land uses, including that of oil palm plantations (USD 7,832 /ha) for which the range of carbon values are almost entirely higher (USD 7,420-22,094 / ha). Te variation with forest on mineral soil is that here the be- low ground carbon losses over a 25-year period are included as well. But there are still considerable measuring challenges for be- low ground carbon because subsidence, water management, and oxidization across time all have an impact on emissions and no standardized measurement procedures exist as of yet. But, like for forest on mineral soils, if a REDD mechanism had been in place much of the forest loss could perhaps have been avoided.
Figure 5: Values of various land uses on mineral soils (top) and peat (bottom). Values for carbon were calculated according to Butler et al. 2009 model (see Figure 4) using a discount rate of 6.5% and voluntary market prices (mean USD 13.33t/CO2
USD 9.43-17, forest carbon report). Under the fixed scenario the carbon price remains constant during the 25-year period and under the appreciation scenario the price increases with 5% each year during the 25-year period. Net present values for the different land uses are from the Tata and van Noordwĳk (2010) and were calculated with a discount rate of 6.5% for a 25-year period. For the carbon calculations potential payments for carbon in land uses other than natural forest were not included be- cause payments for these are still largely under discussion.