Influence of shrubs on soil characteristics and their function in Sahelian agro-ecosystems in semi-arid Niger

doi:10.1006/jare.1999.0609

Journal of Arid Environments

Volume 44, Issue 4, April 2000, Pages 383-398

https://doi.org/10.1006/jare.1999.0609 Get rights and content

Abstract

Soil beneath shrubs form ‘fertile islands’ in fallow sites and millet fields in semi-arid Niger. To gain more information about this phenomena different shrub species in fallow sites following a gradient from 350–650 mm precipitation were examined. For each shrub two different areas were distinguished: an area under the canopy of the shrubs and an area in the nearby open land. Soil samples were taken from a depth of 0–10 cm and analysed for C_org, N_total, P_Bray, pH(H₂O), exchangeable cations, effective cation exchange capacity (ECEC) and soil texture. Significantly higher concentrations between 38–51% for C, N, P and 22% on ECEC for K⁺were found in the soil under the shrubs. The pH showed only slight but significant differences, whereas Al³⁺and H⁺rates on ECEC under the shrubs were increased by 44–55%. For Guiera senegalensis, the most common shrub of the studied area, enrichment ratios of most soil properties increased relatively more with increasing aridity. In general, enrichment ratios decreased with the age of the fallows, whereas concentrations showed no clear evolution. The chemical composition of the shrub litter seems to influence the degree of soil enrichment. The main step of fertile island formation takes place during the cultivation period by trapping wind-blown sediment. This work shows that shrubs are of vital importance for the accumulation of nutrients and maintenance of soil fertility within agro-ecosystems of Niger.

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Regular ArticleInfluence of shrubs on soil characteristics and their function in Sahelian agro-ecosystems in semi-arid Niger

Abstract

Soil Biology & Biochemistry

Journal of Arid Environments

Journal of Arid Environments

Agricultural Systems

Journal of Arid Environments

The effects of trees on their physical, chemical, and biological environments in a semi-arid savanna in Kenya

Journal of Applied Ecology

Biogeochemical cycle of nitrogen in a semi-arid savanna

Oikos

Woody Plants in Agro-Ecosystems of Semi-Arid Regions — with an Emphasis on the Sahelian Countries

Nitrogen — total

Inputs of mineral nutrients and crop residues mulch reduce wind erosion effects on millet in Sahel

Plant-induced soil chemical patterns in some shrub-dominated semi-desert ecosystems of Utah

Journal of Ecology

FAO Production Yearbook 1996

Effet de la texture sur le stockage et la dynamique des matières organiques dans quelques sols ferrugineux et ferrallitiques (Afrique de l'Ouest, en particulier)

Cahiers. ORSTOM, série. Pedologique

Les Grands Traits de la Pédogenèse au Niger Méridional

Soil surface characteristics and variability in the growth of millet in the plateau and valley region of Western Niger

Agriculture, Ecosystems and Environment

Staubdeposition auf Böden West-Afrikas. Eigenschaften und Herkunftsgebiete der Stäube und ihr Einfluß auf Boden und Standortseigenschaften

Untersuchungen zum Einfluß von Büschen auf Standortbedingungen und Artenzusammensetzung von Brachen im Südwest-Niger

Wind reduction downwind from savanna woodland edge

Netherlands Journal of Agricultural Science

Regular Article
Influence of shrubs on soil characteristics and their function in Sahelian agro-ecosystems in semi-arid Niger