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

AbstractRapid 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.

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Faculty Opinions recommendation of The role of land use and land cover change in climate change vulnerability assessments of biodiversity: a systematic review.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.741183991.793590006 ◽

2021 ◽

Author(s):

Jianguo Wu

Keyword(s):

Climate Change ◽

Systematic Review ◽

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Climate Change Vulnerability ◽

Vulnerability Assessments

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Land-use and land-cover change carbon emissions between 1901 and 2012 constrained by biomass observations

Biogeosciences ◽

10.5194/bg-14-5053-2017 ◽

2017 ◽

Vol 14 (22) ◽

pp. 5053-5067 ◽

Cited By ~ 24

Author(s):

Wei Li ◽

Philippe Ciais ◽

Shushi Peng ◽

Chao Yue ◽

Yilong Wang ◽

...

Keyword(s):

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Regional Scale ◽

Model Estimate ◽

Tropical Regions ◽

Vegetation Models ◽

Global Vegetation ◽

Constraint Approach ◽

The Impact

Abstract. The use of dynamic global vegetation models (DGVMs) to estimate CO2 emissions from land-use and land-cover change (LULCC) offers a new window to account for spatial and temporal details of emissions and for ecosystem processes affected by LULCC. One drawback of LULCC emissions from DGVMs, however, is lack of observation constraint. Here, we propose a new method of using satellite- and inventory-based biomass observations to constrain historical cumulative LULCC emissions (ELUCc) from an ensemble of nine DGVMs based on emerging relationships between simulated vegetation biomass and ELUCc. This method is applicable on the global and regional scale. The original DGVM estimates of ELUCc range from 94 to 273 PgC during 1901–2012. After constraining by current biomass observations, we derive a best estimate of 155 ± 50 PgC (1σ Gaussian error). The constrained LULCC emissions are higher than prior DGVM values in tropical regions but significantly lower in North America. Our emergent constraint approach independently verifies the median model estimate by biomass observations, giving support to the use of this estimate in carbon budget assessments. The uncertainty in the constrained ELUCc is still relatively large because of the uncertainty in the biomass observations, and thus reduced uncertainty in addition to increased accuracy in biomass observations in the future will help improve the constraint. This constraint method can also be applied to evaluate the impact of land-based mitigation activities.

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Hydrological implications of land use and land cover change: Spatial analytical approach at regional scale in the closed basin of the Cuitzeo Lake, Michoacan, Mexico

Singapore Journal of Tropical Geography ◽

10.1111/j.1467-9493.2010.00400.x ◽

2010 ◽

Vol 31 (2) ◽

pp. 197-214 ◽

Cited By ~ 7

Author(s):

M.E. Mendoza ◽

G. Bocco ◽

E. López-Granados ◽

M. Bravo Espinoza

Keyword(s):

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Analytical Approach ◽

Regional Scale ◽

Closed Basin

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The role of landscape pattern analysis in understanding concepts of land cover change

Journal of Geographical Sciences ◽

10.1007/bf02873085 ◽

2004 ◽

Vol 14 (S1) ◽

pp. 3-17 ◽

Cited By ~ 6

Author(s):

Jerry A Griffith

Keyword(s):

Land Cover ◽

Land Cover Change ◽

Landscape Pattern ◽

Pattern Analysis ◽

Landscape Pattern Analysis

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Anthropogenic land cover change impact on climate extremes during the 21st century

10.5194/egusphere-egu2020-8595 ◽

2020 ◽

Author(s):

Benjamin Quesada ◽

Souleymane Sy

Keyword(s):

Land Cover ◽

Land Cover Change ◽

Extreme Events ◽

Regional Scale ◽

Extreme Weather ◽

Northeastern Brazil ◽

Eastern Africa ◽

Extreme Weather Events ◽

Rainfall Extremes ◽

Global Mean

<p>Beyond global mean temperatures, anthropogenic land cover change (LCC) can have significant impacts at regional and seasonal scales but also on extreme weather events to which human, natural and economical systems are highly vulnerable. However, the effects of LCC on extreme events remain either largely unexplored at global and regional scale and/or without consensus. Here, using several Earth System Models under two different LCC scenarios (the RCP8.5 and RCP2.6 Representative Concentration Pathways) and analyzing 20 extreme weather indices, we find future LCC substantially modulates projected weather extremes particularly at regional level.</p><p>On average by the end of the 21<sup>st</sup> century, under RCP8.5 and RCP2.6 scenarios, future LCC robustly lessens global projections of high rainfall extremes. Accounting for LCC diminishes regional projections of heavy precipitation days or consecutive wet days by more than 50% in southern Africa or northeastern Brazil but intensifies projected dry days in eastern Africa by 30%. LCC do not substantially affect projections of global and regional temperature extremes projections (<5%), but it can impact global rainfall extremes 2.5 times more than global mean rainfall projections.</p><p>Under RCP2.6 scenario, global LCC impacts are similar but of lesser magnitude while at regional scale in Amazon or Asia, LCC enhances drought projections. We investigate the underlying biophysical drivers behind those projected changes.</p><p>We stress here that multi-coupled modelling frameworks incorporating all aspects of land use-land cover change and more model-data benchmarking are needed for reliable projections of extreme events.</p><div> <div>&#160;</div> </div>

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Effects of land cover change on temperature and rainfall extremes in multi-model ensemble simulations

Earth System Dynamics Discussions ◽

10.5194/esdd-3-597-2012 ◽

2012 ◽

Vol 3 (2) ◽

pp. 597-641 ◽

Cited By ~ 2

Author(s):

A. J. Pitman ◽

N. de Noblet-Ducoudré ◽

F. B. Avila ◽

L. V. Alexander ◽

J.-P. Boisier ◽

...

Keyword(s):

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Regional Scale ◽

Extreme Temperature ◽

Daily Maximum ◽

Temperature Extremes ◽

Rainfall Extremes ◽

The Impact ◽

Change In Mean

Abstract. The impact of historical land use induced land cover change (LULCC) on regional-scale climate extremes is examined using four climate models within the Land Use and Climate, IDentification of robust impacts project. To assess those impacts, multiple indices based on daily maximum and minimum temperatures and daily precipitation were used. We contrast the impact of LULCC on extremes with the impact of an increase in atmospheric CO2 from 280 ppmv to 375 ppmv. In general, changes in both high and low temperature extremes are similar to the simulated change in mean temperature caused by LULCC and are restricted to regions of intense modification. The impact of LULCC on both means and on most temperature extremes is statistically significant. While the magnitude of the LULCC induced change in the extremes can be of similar magnitude to the response to the change in CO2, the impacts of LULCC are much more geographically isolated. For most models the impacts of LULCC oppose the impact of the increase in CO2 except for one model where the CO2-caused changes in the extremes is amplified. While we find some evidence that individual models respond consistently to LULCC in the simulation of changes in rainfall and rainfall extremes, LULCC's role in affecting rainfall is much less clear and less commonly statistically significant, with the exception of a consistent impact over South East Asia. Since the simulated response of mean and extreme temperature to LULCC is relatively large, we conclude that unless this forcing is included we risk erroneous conclusions regarding the drivers of temperature changes over regions of intense LULCC.

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