Global Land degradation as ‘debts’
We define as environmental debt: (a) the difference between natural forest potential and actual tree cover globally, and aggregated by latitude and by world region, (b) the difference between natural soil erosion and actual soil erosion globally, and aggregated by latitude and by world region, (c) the difference between natural above-ground carbon and actual above-ground carbon globally, and aggregated by latitude and by world region, (d), the difference between natural below-ground carbon and current below-ground (0–30 cm) carbon globally, and aggregated by latitude and by world region.
a) Global tree cover debt, naturally, there could be 4.6 Gha of tree cover but currently there are only 3.2 Gha, so the global tree cover debt is 1.4 Gha (correspondingly, if we define forests as areas with >10% tree cover, naturally there could be 8.8 Gha, currently there are 5.9 Gha, and the implied forest debt is then 2.9 Gha;
b) The natural rate of soil erosion would be 10 Gt per year, but currently, it is 36 Gt. Thus, global soil erosion debt is 26 Gt –and rising
c) The above-ground biomass would naturally be 871 Gt C, but currently, it is only is 601 Gt C . This means that global above-ground carbon debt is 270 Gt C.
d) Below-ground carbon, naturally, there would be 899 Gt C, but currently, there are only 863 Gt C, which means that global below-ground carbon debt is 36 Gt C .
Title: Global land degradation as Debts.
Description: Datasets as ‘debts’ for a) tree cover, b) soil erosion c) above ground carbon d) below ground carbon. Environmental Debt is the difference between natural potential condition and current condition.
Spatial coverage: Global
Pixel size: 0.4 degrees
Measurement Unit: Erosion = Mg/ha/yr. Tree cover = ha per Km2 . Carbon above-ground = Mg C/ha. Carbon below-ground = Mg C/ha.
Data available: Four raster files (TIFF) (at 0.4 degrees resolution) are available. tree cover, soil erosion, above ground carbon and below ground carbon. Details about the input data/methodology/ units can be found in the Supporting information of the article. The original datasets belong to Hanset et al. (2013) (tree cover), Borrelli et al., (2017) (soil erosion), Bastin et al. (2019) (above-ground carbon), Sanderman et al., (2017) (below ground carbon).
Wuepper, D., Borrelli, P., Panagos, P., Lauber, T., Crowther, T., Thomas, A. and Robinson, D.A., 2021. A ‘debt’ based approach to land degradation as an indicator of global change. Global Change Biology, 27(21): 5407-5410.