Accelerating land cover change in West Africa over four decades as population pressure increased

Abstract

Rapid population growth in West Africa has exerted increasing pressures on land resources, leading to observable changes in the land cover and land use. However, spatially explicit and thematically detailed quantitative analyses of land cover change over long time periods and at regional scale have been lacking. Here we present a change intensity analysis of a Landsat-based, visually interpreted, multi-date (1975, 2000, 2013) land cover dataset of West Africa, stratified into five bioclimatic sub-regions. Change intensities accelerated over time and increased from the arid to the sub-humid sub-regions, as did population densities. The area occupied by human-dominated land cover categories more than doubled from 493,000 km2 in 1975 to 1,121,000 km2 in 2013. Land cover change intensities within 10 km of new settlement locations exceeded the region-wide average by up to a factor of three, substantiating the significant role of population pressure as a force of change. The spatial patterns of the human footprint in West Africa, however, suggest that not only population pressure but also changing socioeconomic conditions and policies shape the complexity of land cover outcomes.

The evolution of built-up areas in Ghana since 1975

“…They find that urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact during their study period. Similar findings are reported in [ 6 – 9 , 24 ]. Evidence in Seto et al [ 3 ] shows that urban land expansion in Africa is driven largely by population growth and has a weak relationship with GDP growth.…”

“…This paper contributes to the literature on urbanization and regional development [ 3 , 6 – 9 , 13 , 23 , 24 ]. Seto et al performed a meta-analysis of urbanization between 1970 and 2000 in developing countries and found the urbanization rate in Africa to be one of the fastest [ 3 ].…”

“…A number of studies have examined the form and compactness of cities [14,15] and their impacts on urban productivity [16][17][18], as well as the role of urban transit [19,20] and land tenure regulation [21,22] in shaping the urban space in developing countries. Several studies have used satellite and remote sensing data to document and forecast expansion of urban land cover at the global scale [6][7][8][9]23] and for West Africa [24]. However, research on the evolution of lower density cities/towns has been limited despite its importance for policies regarding provision of infrastructure, housing and other services.…”

Multiple trajectories of grassland fragmentation, degradation, and recovery in Russia's steppes

“…In Mongolia, mining has imposed a dramatic negative impact on steppes (Suzuki, 2013). The savannas of Saharan and subSaharan Africa are under pressure from agricultural expansion, mining, and wood extraction, including charcoal production (Herrmann et al, 2020;Mensah et al, 2020;Ordway et al, 2017). Due to their conversion to various land uses, rangelands in the Middle East are under pressure due to their conversion to various land uses (Mazloum et al, 2021).…”

Modeling the Underlying Drivers of Natural Vegetation Occurrence in West Africa with Binary Logistic Regression Method

“…On the contrary, Lambin et al [14] were of the view that climate variability alone is not sufficient to explain the natural vegetation change in Africa. Some other studies relate changes in natural vegetation to either population growth or improved accessibility, poverty, the land tenure system, and so forth [21][22][23][24]. Boschetti et al [25], Brandt et al [26], Rishmawi and Prince [27], and Leroux et al [28] highlighted that interplay of multiple factors drive a natural vegetation change in Africa.…”