Soil rehabilitation through afforestation: evaluation of the performance of Eucalyptus and pine plantations in a Nigerian Savanna environment

Abstract

On the outskirts of Zaria, northern Nigeria, Eucalyptus camaldulensis and Pinus oocarpa plantations have been established to satisfy both land rehabilitation and agroindustrial objectives. Soils of the plantations and adjacent unafforested degraded sites where major in¯uences from soil type and management were minimal were sampled to provide data for a parallel investigation of the effect of afforestation on soil rehabilitation. Three adjacent age±grade plantations in respect of each tree species were involved. These are 6, 13 and 27 years for eucalyptus, and 7, 15 and 25 years for pines. Results obtained showed that the rate of soil regeneration in the context of present silvicultural practices is extremely slow. Of the soil parameter studies, only organic matter shows signi®cant improvement within the examined time frame. The soil texture, bulk density, in®ltration rate, nutrient elements and pH showed only slight improvement. There was little evidence to suggest that either of the tree species had a more bene®cial effect on the soil than the other. The signi®cance of the results is discussed in terms of land-use decision and policies in Nigeria towards a sustainable afforestation programme.

Soil Quality Variation under Enset based Conservation Tillage and Cereal based Conventional Tillage System in Southern Highlands of Ethiopia

“…The higher clay at 0-15 cm soil depth on CBCVTS might be due to intensive and continuous cultivation which may reduces downward movement of clay particles within the soil profile. This finding is in agreement with findings of Jaiyeoba [28]. The higher sand fraction on CBCTS was due to selective removal of clay fraction by erosion [29][30][31][32][33][34].…”

Influence of individual oak (Quercus robur) trees on saturated hydraulic conductivity

“…While most studies support the idea that trees enhance K s (Table 1), the results of some suggest that this is not universally true. For example, Jaiyeoba (2001), investigating the effect of reforestation on degraded land in Nigeria, found that a significant increase in K s was observed under only one of the six plantations studied. Yeates and Boag (1995) reported higher soil permeability in pasture compared with the Pinus radiata agro-forestry systems in their study.…”

Evaluation of soil fertility in the succession of karst rocky desertification using principal component analysis

“…For example, during the investigation of stands, we found that some karst regions with higher grades (moderate RD (MRD) or intensive RD (IRD)) had been enclosed for afforestation. This measure is beneficial to rehabilitation and sustainable management of karst lands (Jaiyeoba, 2001).…”