Decomposition and nutrient release from leaves of some common agroforestry tree/shrub species of Sudano-Sahelian West Africa

TL;DR

This study examines how leaves from common agroforestry trees and shrubs in West Africa decompose and release nutrients, finding that leguminous species and rainy seasons speed up the process.

Contribution

The study provides new insights into seasonal and species-specific decomposition rates of agroforestry leaves in the Sudano-Sahelian region.

Findings

Decomposition rates were 155% higher in the rainy season compared to the dry season.

Leguminous tree leaves decomposed 1.4 times faster than non-leguminous ones.

Nutrient release timing should align with crop needs by considering species and season.

Abstract

Foliar inputs from indigenous agroforestry tree/shrub provide organic matter and nutrients to sustain crop production in the West African Sahelian region. This study aims at monitoring the decomposition and nutrients release of leafy biomass of selected agroforestry tree and shrub species. In Mali and Burkina Faso, fresh leaves were collected from leguminous trees (Faidherbia albida (Delile) A. Chev., Pterocarpus lucens Lepr.) and non-leguminous trees (Vitellaria paradoxa C.F. Gaertn., Khaya senegalensis (Desr.) A. Juss.) and in Senegal, fresh leaves were obtained from leguminous trees (Faidherbia albida (Delile) A. Chev., Pterocarpus lucens Lepr. and Piliostigma reticulatum (DC.) Hochst.) and the non-leguminous tree Guiera senegalensis J.F. Gmel. The leaf samples collected during the dry and rainy seasons were deployed for decomposition and nutrient release experiments using the litter bag technique. Average decomposition rate for this study was 0.23 k week− 1 whereby the rate of decomposition was 155% higher in the rainy season than in the dry season. Average decomposition rate of leguminous tree and shrub leaves was 1.4-folds greater than that of non-leguminous counterparts. To optimize the synchronization of nutrient release from green manure with crop nutrient demands, manure should be co-applied considering seasonal and species effects.

The online version contains supplementary material available at 10.1038/s41598-025-29117-9.

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