Different regulation processes of litter phosphorus loss for leaf and root under subtropical afforestation.

Background and aims: Decomposition of leaf and root litter contributes large amounts of phosphorus (P) to soil and is strongly determined by litter quality, morphology, and microbial activity, but the individual and interactive roles of these factors remain underexplored. Methods: To fill this gap, field litter decomposition experiment was conducted by collecting leaf and fine root litters (< 2 mm) of crop (from cropland), shrub (from shrubland) and wood (from woodland) and placing the litters into woodland soil for 2 years in subtropical China, in order to evaluate effects of the above factors on leaf and fine root litter P loss of three species among different decomposition stages. Results: Leaf litter P loss was positively correlated with root P loss, and both were primarily controlled by microbes. Leaf litter P loss was more affected by litter quality, while root litter P loss was more affected by morphology during whole decomposition. However, morphology and litter quality were also important controls of leaf P loss at mid-to-late stages and of root P loss at early-to-mid stages. Conclusion: Our results highlighted that microbes exerted dominant controls with different importance of litter morphology and litter quality during different decomposition, which weakened the coordination between leaf and root decomposition. Overall, different regulation processes of leaf and root litter P loss and associated drivers at different decomposition stages provided novel insight into accurately predicting litter decomposition related to nutrient cycling under future afforestation. [ABSTRACT FROM AUTHOR]