|• In situ litter production||• The productivity of plant community at a site has a strong influence on in situ litter production (Bray and Gorham 1964).|
|• Deposition of litter from outside the system||• The deposition of exogenous litter and the removal of the native litter have a strong impact on litter accumulation (Becker et al. 2015).|
|• Litter destruction by physical and biotic agents||• Physical and chemical degradation, decomposition, and heterotrophic consumption may reduce the mass of in situ litter accumulated (Andren and Paustian 1987; Olson 1963).|
• Decomposition rates vary greatly among ecosystems (Andren and Paustian 1987).
|• Removal of litter||• The main cause for the disappearance of litter from any open sites is the removal of fragmented litters from open sites due to runoff, geometry of shrubs, and wind and water flow (Becker et al. 2015).|
|• Temporal variations||• Accumulated litter may vary due to transient environmental fluctuation on successional and seasonal time scales (Andren and Paustian 1987; Olson 1963).|