Countries facing development pressures
Our results suggest that the risk of conversion follows existing patterns of development with the three most converted regions: Central America, Europe and South Asia; remaining the most converted after accounting for future development risk. In marked contrast, Africa and South America,which are currently among the least converted regions, also have the highest amount of land under potential development risk (8.18 and 4.32 million km2 for Africa and South America, respectively). Hence, when development risk is accounted for the amount of converted lands could approximately double for South America and triple for Africa.
“The amount of converted lands could approximately double for South America and triple for Africa.”
Lands at Risk by Biomes
General Patterns of Development Risks for the Earth’s Biomes
Biomes are large naturally occurring community of flora and fauna occupying a major habitat. We examined potential conversion at this generalize level to help understand the stresses placed on these communities. We found that currently, 21% of all biomes have half of their natural habitats converted and 57% have more than a quarter converted. Future development could lead to half of the world’s biomes having more than 50% of their natural habitats converted, and all biomes (with the exception of Boreal Forests and Tundra) with over 25% of their natural lands at risk of conversion.
While development risk is highly dispersed globally, potential impacts are disproportionally borne by three biomes that contain 66% of delineated at-risk natural areas: Tropical and Subtropical Grasslands, Savannas, and Shrublands (5.98 million km2); Deserts and Xeric Shrublands (3.74 million km2); and Tropical and Subtropical Moist Broadleaf Forests (3.4 million km2). Accounting for current and potential future development, three biomes could become predominantly human-modified: Tropical and Subtropical Dry Broadleaf Forests (83%), Mangroves (72%), and Temperate Broadleaf and Mixed Forests (71%).
“If present trends continue, half of the world’s biomes will have more than 50% of their natural habitats converted.”
Lands at Risk by Terrestrial Ecoregions
A Closer Look at Development Risks for the Earth’s Terrestrial Ecoregions
Terrestrial ecoregions are uniquely defined landscapes across the globe based on distinct collection of species, natural communities, and environmental conditions. Of the 867 terrestrial ecoregions world-wide, we examined the development risk of 737 of these and found the number of ecoregions with 50% or more of land at risk of conversion nearly doubles from 235 ecoregions to 419 ecoregions with 142 additional ecoregions having the potential of 75% of the land being converted. Of these 142 ecoregions, 41 will shift from having less than 25% of the lands converted to over 75% and overall 88 ecoregions will see a jump in conversion greater than 50%. These substantial changes in conversion are projected for Central and Eastern Africa, Southern and Western South America and within the Central Rocky Mountain Region of North America. When examining the potential conversion of what is currently natural, we identify 224 ecoregions that have 50% or more of natural habitat at risk to development.