Afforestation potential in the WANA region to sequester carbon and improve soil quality

Abstract

The region of West Asia and North Africa (WANA) is characterized by hot, dry climates which provide little support for vast areas of forests. This region currently contains 106.3 million ha of forests, which represents a 4 % decrease since 1990. These forests have suffered from a long history of degradation and over exploitation which has impacted soil quality and in some cases caused desertification to occur. Afforestation has benefits of sequestering C, stabilizing soil, and placing C and other elements into the soil, thus rehabilitating the soil. Many different tree species have been examined for afforestation purposes within the WANA region, and great care needs to be given to match species with site. Early successional and edaphic climax species may be candidates as they are typical of harsh environments. Based on reported species, C sequestration rates will vary from 0.3 to 3.6 tC/ha/year. Afforestation will enhance the sequestering of C in the soil, but only if the plantations exist on the site for relatively long periods. Most C is sequestered in the forest floor and the upper soil layer in the initial years after planting from the litter that begins to accumulate.