The role of litterfall production, decomposition and litter nutrient interplay under land use influences: implication to ecosystems health in Aleta Chuko, Ethiopia

Investigating litterfall, its decomposition rate and nutrient content is important for predicting nutrient cycling in agroforestry. The study aimed to measure litterfall of seven woody species in Coffee-Enset agroforestry (CEA) and eucalyptus camaldulensis in woodlots, determine the decomposition rate, nutrient contents and nutrient returns of leaf litter. Samples were taken over three transect lines with three replicates for each species litterfall and decomposition experiments for one year using litter traps and nylon-mesh litter bags, respectively. Monthly litterfall ranged from 40.9 g m⁻² for C. arabica to 79.7 g m⁻² for O. kenyensis in CEA, and 54.8 g m⁻² for E. camaldulensis. Litterfall was significantly different among the studied species (p < 0.05). Decay constants significantly differed among the species (p < 0.05). C. arabica was the fastest (2.4) while E. camaldulensis was the slowest (1.1). C. africana contributed significantly higher return of Phosphorus (1.05 g m⁻²) and Potassium (11.72 g m⁻²) (p < 0.05). M. ferruginea (16.2 g m⁻²) and O. kenyensis (14.1 g m⁻²) showed significantly higher nitrogen returns (p < 0.05), while E. camaldulensis showed higher Sodium (.41 g m⁻²) return which should be a concern to be addressed. There was a significant loss of initial litter Potassium, Calcium, and Magnesium for all studied species during yearly decomposition (p < 0.05). Higher litterfall species (O. kenyensis, C. africana, and P. americana) are preferable for carbon returns. Fast decaying litters with higher content of N, P and K are useful for enhancing soil fertility and composting.