Global land use transitions and their drivers during 1960-2019

Abstract

<p>Land use/cover change is central to understanding the global sustainability challenges of climate change, biodiversity loss, and food security. Yet, while the magnitude of global land use has often been studied, little is known about land use transitions and their drivers, and how these vary across the world. A major obstacle has been the lack of consistent long-term data with sufficiently high resolution.<br>Here we analyse the drivers of major global land use transitions based on a novel high-resolution land use reconstruction, HILDA+ (Historic Land Dynamics Assessment+). We (1) identify key land use transitions and their spatiotemporal patterns and (2) correlate national time series of annual land use transitions with a range of influencing variables that represent indirect drivers (demography, politics and economics) and direct drivers (production and environment) across the globe.<br>We identify 12 major land use transitions and find that agricultural expansion accounted for the largest share of global land use change (~7.6 million km<sup>2</sup>), an area as large as Greece every year between 1960 and 2019. A major portion of this land is made up of pasture/rangeland expansion, mainly used for nomadic pastoralism. Areas of cropland expansion are mainly located in the Global South, particularly in South America (Argentina, Brazil), Africa (Ethiopia, Nigeria, Uganda), India and Thailand. Here we notice a shift of agricultural expansion from South America to Africa since the late 1980s. Globally, forest loss (~3.6 million km<sup>2</sup>), including deforestation for pasture/rangelands or cropland and forest degradation to shrub/grassland, outweighed forest expansion (~2.6 million km<sup>2</sup>) during 1960-2019. Whereas forestry, crop-pasture dynamics and cropland abandonment dominated in the Global North, deforestation, forest degradation and agricultural expansion are major transitions of the Global South.<br>Our driver analysis reveals that economic factors are the largest indirect drivers of global land use transitions in terms of area (~6.7 million km<sup>2</sup>). Of these, Gross Domestic Production (GDP) is the strongest driver in the Global North, mainly for forest expansion, forestry and urban growth. In contrast, wage and cereal price lead the list in the South, mostly related to agricultural expansion. Indirect-direct driver combinations of economy with production (~4.7 million km<sup>2</sup>), politics with production (~3.2 million km<sup>2</sup>) and demography with production (~2.3 million km<sup>2</sup>) affected the largest areas. We find that environmental indicators have a greater influence on land use change in the South, related to deforestation or desertification, than in the North, linked to crop-pasture dynamics. Indirect drivers show higher correlations than direct drivers, which underlines the importance of social systems on the extent and speed of land use change.<br>Giving new data-driven and quantitative insights into a largely untouched field, we reveal the importance of indirect drivers from economy, politics and demography for land use transitions across the globe. Learning from the recent past, understanding how socio-economic and environmental factors affect the way humans use the land surface is essential for estimating impacts of land use change and implementing measures of climate mitigation and sustainable land use policies. With our findings, we can make a contribution to this.</p>