Santo Antão and Santiago are the two largest islands of the archipelago of Cabo Verde (991 sq km and 754 sq km, respectively). Following the colonization of the islands in the late 1400s, the fragile environment of these relatively recent volcanic mountains, associated with the arid and semiarid sahelian climate, underwent a severe deterioration (Spaak, 1990). The land degradation problems led to large afforestation programs after independence in 1975, which restored more than 800 sq km of land and drastically changed the landscape of Cabo Verde.
Santo Antão and Santiago islands are characterized by a dramatic landscape with steep slopes, associated with a strong orographic effect. Their soils are generally young, shallow, and very susceptible to erosion. The climate varies from humid to arid, with a short rainy season from August to October and periodic multi-year droughts. Rainfall varies widely from place to place and year to year, ranging anywhere from 50 to 1400 mm (Eklund and Kronhamn, 2002).
Since the 1980s, afforestation has focused mainly on the arid zones of Santiago and Santo Antão, where the annual rate of afforestation was 57 sq km (Santiago received about 80 percent, or 45 sq km). This was a big step toward land restoration (Eklund and Kronhamn, 2002). The goals of all afforestation efforts were to 1) provide soil erosion control by mechanical and vegetative methods; 2) increase infiltration, fog capture, and water availability; 3) increase biodiversity and vegetative cover; and 4) increase economic aspects of forests such as firewood, employment, or timber (Benton, 2013). Over the past 40 years, the forest has had a great importance in the context of combating desertification by rehabilitating vegetation cover, meeting energy needs and forage production, developing agrosilvopastoral systems, as well as having undoubtedly contributed to a significant increase in the diversity of the landscape in Cabo Verde (Lopes and Santos, 2010). The former degraded areas of Santiago and Santo Antão islands are now covered by a dense forest in the mountainous parts, and woodland in the drier areas.
The first image pair (above) shows an example of afforestation on humid highland in Santo Antão. In 2003 (left), forest and woodland already existed on some of the slopes and highland areas, resulting from earlier afforestation projects in the 1970–1980s. In the early 2000s, new plantations were implemented on slopes but the trees were not visible yet in 2003. In 2014, however, the forest became denser and new woodland and growing plantations appeared on the lower slopes. Afforestation continues and several programs have been implemented in the late 2000s, especially in Santiago and Maio, but not to the same extent as before.
In the second image pair (above), high resolution images show the afforestation on arid land in Santiago (8 km northwest of Praia). In 2002, an afforestation project just started to restore the degraded steppe. The trees might have been planted but are not visible in the imagery. In 2014, the whole area was covered by dense plantations.
Today, 67 percent of the total reforested area in Cabo Verde is located in Santo Antão or Santiago, and represents 7 percent of the country area (about 300 sq km). The afforestation also had a great impact on the local population. Forests are perceived to provide numerous benefits to communities, especially to the poorer rural interior of the island. Since the beginning of the afforestation program, major positive changes in vegetation, land use, and infrastructure can be observed.
Afforestation is one of the key technologies to address the fragility of ecosystems: it provides better protection against erosion and makes better use of rainfall in order to maintain the sustainability of agricultural systems (WOCAT, 2015). The forests of Cabo Verde present an enduring example of positive land use change in West Africa. They are heavily utilized by the local population to meet many needs and are viewed favorably. While simple changes in forest management practices could improve biodiversity conservation and increase economic activity, many valuable lessons can be learned from Santo Antão and Santiago, and applied in other West African afforestation projects.