Influence of Litter Quality and Mesh Size on Decomposition Dynamics and Nutrient Release Patterns of Selected Tropical Plant Residues

Abstract

In tropical agroecosystems, the decomposition of plant residues constitutes a fundamental 
biogeochemical process governing soil fertility maintenance and nutrient cycling. This study 
quantitatively evaluated the influence of litter quality and litterbag mesh size on 
decomposition kinetics and nutrient mineralization patterns of selected tropical plant 
residues. A controlled litterbag experiment was established using six residues commonly 
encountered in tropical farming systems: banana leaves, Chromolaena odorata, Leucaena 
leucocephala, maize (Zea mays) stover, neem (Azadirachta indica) clippings, and Panicum 
maximum. Air-dried residues were placed on the soil surface within নাইlon litterbags of two 
mesh sizes (0.5 mm and 5.0 mm) to differentiate microbial-driven decomposition from 
combined microbial–mesofaunal activity. Litterbags were retrieved at 7, 14, 28, 49, and 98 
days after placement to determine residual mass and quantify nutrient release dynamics for 
nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). Progressive mass 
loss was observed across all residues, indicating active decomposition and organic matter 
turnover. During the early decomposition phase (7–28 days), residue type exerted negligible 
influence on mass loss; however, significant differentiation emerged during the later stages 
(49–98 days), reflecting substrate-specific recalcitrance and lignocellulosic composition. Mesh 
size exerted a consistently significant control on decomposition rates, with finer mesh (0.5 
mm) restricting faunal access, thereby resulting in greater litter mass retention and slower 
nutrient release relative to the coarser mesh (5.0 mm). Nutrient release trajectories varied 
systematically with litter quality. Nitrogen and phosphorus exhibited residue-dependent 
mineralization patterns, underscoring the role of initial nutrient content and C:N ratios. 
Potassium displayed rapid early-stage leaching attributable to its high solubility and weak 
structural binding within plant tissues. In contrast, calcium and magnesium demonstrated 
gradual release profiles associated with the breakdown of structural components such as cell 
walls. Overall, the interaction between residue quality and decomposer accessibility highlights 
the pivotal role of both substrate characteristics and soil biota in regulating decomposition 
processes and nutrient cycling, with direct implications for optimizing residue management 
strategies and enhancing soil productivity in tropical agroecosystems.