Mapping Trade Driven Land Use Change and Consequent Biodiversity Loss due to Future Global Population Increase

Past studies using the multi-region input-output analysis demonstrated that the import of land-intensive products in high-income countries drives biodiversity loss in countries along the Equator. But this type of analysis does not account for price induced changes in human consumption and production, thereby missing key dimensions of biodiversity loss. We fill this gap by using the Global Trade Analysis Project (GTAP) global general equilibrium model, where resource endowments are finite and prices are endogenously determined via supply and demand. We propose an economic framework that accounts for how trade patterns are expected to change in response to changing relative prices. We simulate the impact of a one million population increase in each of the 37 world regions and focus on the consequences for regional production, consumption and trade patterns, and project changes in cropland, pasture, and forestry land use areas in each region. These are then translated into biodiversity impacts (the increase in number of species threatened with extinction) within 18 agro-ecological zones in each region.

We show that the increase leads to a growth of 2 million hectares of cropland and around 200,000 hectares of pastureland, a loss of half a million hectares of natural undisturbed vegetation, and conversion of 1.6 million hectares of managed forests into crop and pastureland. The regions projected to suffer the most species loss due to this are Indonesia, Madagascar, and South and Central America. We also identified three mechanisms driving the land use change: domestic substitution of imports, direct increases in exports to satisfy the increased population abroad, and indirect increases in trade through competition in third markets.

In this context, we note that geography matters: while historical trade patterns are crucial, trade connections evolve over time in response to changing demand. Hence, it is not proper to assume that trade linkages are fixed. The latter message is exemplified by putting all regions on an even ground with small population increases. Our analysis reveals that the impact of adding more people on the planet depends on where the population growth occurs. With uneven population growth expected in the future, we expect biodiversity hotspots to also evolve. Our framework can shed light on these changes.