Mapping Land Use Land Cover Transitions at Different Spatiotemporal Scales in West Africa

Abstract

Post-classification change detection was applied to examine the nature of Land Use Land Cover (LULC) transitions in West Africa in three time intervals (1975–2000, 2000–2013, and 1975–2013). Detailed analyses at hotspots coupled with comparison of LULC transitions in the humid and arid regions were undertaken. Climate and anthropic drivers of environmental change were disentangled by the LULC transitions analyses. The results indicated that human-managed LULC types have replaced the natural LULC types. The total vegetation cover declined by −1.6%. Massive net gains in croplands (107.8%) and settlements (140%) at the expense of natural vegetation were detected in the entire period (1975–2013). Settlements expanded in parallel with cropland, which suggests the effort to increase food production to support the increasing population. Expansion of artificial water bodies were detected in the humid regions during the period of 1975–2000. Nonetheless, shrinking of water bodies due to encroachment by wetlands and other vegetation was observed in the arid regions, coupled with net loss in the whole of West Africa. The results indicate deforestation and degradation of natural vegetation and water resources in West Africa. Underlying anthropic drivers and a combination of anthropic and climate drivers were detected. LULC transitions in West Africa are location specific and have both positive and negative implications on the environment. The transitions indicate how processes at the local level, driven by human activities, lead to changes at the continental level and may contribute to global environmental change.

Recent Changes in Hydroclimatic Patterns over Medium Niger River Basins at the Origin of the 2020 Flood in Niamey (Niger)

“…Despite small-scale landscape degradations which could still lead to relevant modifications in the hydrological processes, at basin scale runoff and precipitation grow accordingly. In Dargol basin, where anthropogenic factors are stronger and intense, LULC changes occurred between 2000 and 2013 [62] and a lower vegetation recovery was observed [23]. Nevertheless, the strong deceleration of RC increases in the last period suggesting that runoff increase is currently driven mainly by rainfall.…”

“…The Sirba basin behaviour still responds to the first Sahelian Paradox because flow growth surpasses the precipitation one. Some studies in northern Burkina Faso show that LULC changes were still ongoing during the first decade of the 21st century [62] bringing soil surface changes, but to our best knowledge no published study has analysed LULC changes during the last decade. Descroix et al [15] highlighted in a bibliographic review that this region was poorly affected by the regreening.…”

Land-Use and Land-Cover (LULC) Change Detection and the Implications for Coastal Water Resource Management in the Wami–Ruvu Basin, Tanzania

“…Worldwide, LULCCs have been triggered by natural and anthropogenic factors [10,11]. The increasing pressure of anthropogenic factors has substantially altered numerous watersheds connected to coasts [12,13], particularly in developing countries due to population growth and development activities [14,15].…”

Monitoring the Spatiotemporal Evolution of the Green Dam in Djelfa Province, Algeria

“…Land degradation and desertification (LDD) are the main reasons for the rapid changes affecting the majority of the earth's drylands, resulting in an overall loss of habitats and changes in vegetation cover, plant composition, hydrologic conditions and soil properties [1]. Land-use changes, such as crops and urban expansion and global climate change (mainly recurrent droughts) are considered the main drivers of LDD in dryland ecosystems [1][2][3]. Understanding the dynamics and processes of Land-Use and Land-Cover (LULC) changes has thus become a central objective in research dealing with the dynamic relationships between humans and the environment at all scales, from local to global [4].…”