Abstract
Overgrazed rangeland (200 mm annual rain) has been planted with Pinus halepensis and Acacia saligna in 1983 as part of a “green belt” concept against desert encroachment. A first evaluation was carried out in 1996. The plantings survived because they were government plantations. The overall coverage was estimated at 50 to 65% Pinus reached a mean height of 3.8 m and a stem diameter (DBH) of 4.5 cm varying with slope position. The Acacia trees were smaller (2.6 m) but had a larger crown coverage (20 against 5.4 m2) and a thicker stem diameter. The planted and protected area had a denser ground cover than the area unprotected against grazing (64 against 13 g/m2). Weight contribution of different species is provided. An enrichment in C of the soil under the plantation was estimated but was not statistically significant. A positive effect of the plantation is seen in the protection and the consequently denser cover of the ground vegetation.
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