Land Cover

The next step for two strong land cover products at USGS EROS is to combine them to create something even better.

In contrast to the discrete land use and land cover classes, land productivity is a continuous variable, which represents land cover through vegetation density and vigor. Land productivity can indicate the land’s ability to support and sustain life and is useful for identifying land degradation. A common measure of land productivity is derived from time series of the Normalized Difference...

West Africa’s climate is controlled by the interaction of two air masses, the influence of which varies throughout the year with the north-south movement of the Intertropical Convergence Zone (ITCZ). Hot, dry continental air masses originating from the high pressure system above the Sahara Desert give rise to dusty Harmattan winds over most of West Africa from November to February. In summer...

With a 2015 population of 367 million (UN, 2015), West Africa is home to 5 percent of the world’s population. This is a five-fold increase in population since 1950, when 73 million people lived in the region, which makes West Africa the fastest growing of any of the world’s regions. For comparison, the world population has increased less than three-fold during the same time period. The young age...

Changes in land use and land cover result from a myriad of factors acting on the land surface.

Below is an example of a W-ARly-Pendjari (WAP) complex ecological case study illustrating the change over 30 years. There are 29 additional case studies available that explore the distinct transformations happening in the landscapes of West Africa, with one to two studies for each country. For the complete collection, refer to the Landscapes of West Africa Atlas.

Biological diversity, or biodiversity, can be defined as the full array of life in a region, including species richness, ecosystem complexity, and genetic variation. Biodiversity may be the greatest natural resource, as it is a source of food, fuel, medicines, clothing, building materials, clean water, tourism and many other benefits (Norse and others, 1986). Biodiversity possesses marked economic...

The map of ecological regions of West Africa captures the variety and complexity of West Africa’s landscapes and presents a way of organizing them into smaller units. Ecological regions, or ecoregions, are areas of relative homogeneity with respect to ecological systems involving the interrelationships of plants, animals, and their environment. Ecoregions are a holistic concept: The spatial...

From north to south — from the Sahara to the humid southern coast — West Africa can be subdivided into five broad east-west belts that characterize the climate and the vegetation. These are the bioclimatic zones known as the Saharan, Sahelian, Sudanian, Guinean, and Guineo-Congolian Regions, shown in the map above. The lines between these regions represent more of a transition along a continuous...

The 8 million square kilometers and 17 countries covered by this atlas encompass a wide range of landscapes from alluvial valleys in Senegal and Ghana, sandy plains and low plateaus across the Sahel, and rolling hills of Togo to rugged mountains with summits reaching over 1,500 m in Guinea and 1,800 m in Niger. Covering approximately one quarter of Africa, West Africa contains a broad range of...

West Africa’s population is expected to double by 2050, increasing the demands on already limited land, water, and forest resources. The region’s landscapes are already affected by degradation, particularly in the fast growing agricultural lands where natural vegetation cover has been removed, and fragile soils have been exposed to wind and water erosion. Since 1975, West African forests have...

The Upper Guinean forest of West Africa, identified over 20 years ago as a “global biodiversity hotspot” due to its exceptional concentrations of endemic species and exceptional loss of habitats, encompasses all of the lowland forests of West Africa (Mittermeier and others, 1999; Myers and others, 2000). The forest ecosystem extends from southern Guinea into eastern Sierra Leone, through Liberia...