The Effects, Patterns and Predictors of Phosphorus Addition on Terrestrial Litter Decomposition

ABSTRACT Aim Anthropogenic phosphorus (P) input profoundly affects carbon (C) and nutrient dynamics in terrestrial ecosystems, which poses a threat to soil health and nutrient sustainability. Litter decomposition is crucial for maintaining soil C and nutrient pools, yet there is a significant knowledge gap regarding the effects of anthropogenic P input on terrestrial litter decomposition. Location Terrestrial ecosystems. Time Period 1985–2024. Major Taxa Studied Litter decomposition. Methods We conducted a meta‐analysis based on 731 observations from 40 peer‐reviewed articles to determine the overall effects, patterns and primary predictors of P addition on litter decomposition. Results The results showed that P addition increased the activities of β‐1,4‐glucosidase (BG) and β‐1,4‐N‐acetylglucosaminidase (NAG) during decomposition and accelerated the degradation of lignin and cellulose and the release of litter C. This resulted in a 6.63% increase in litter mass loss. The positive effect of P addition on litter mass loss was further amplified when combined with N addition. In addition, the patterns varied depending on P fertiliser type (e.g., Ca(H 2 PO 4 ) 2 , NaH 2 PO 4 , and KH 2 PO 4 ), P addition level (e.g., < 5, 5–10 and > 10 g P m −2 year −1 ), experimental duration (e.g., < 12, 12–24 and > 24 months), litterbag mesh size (e.g., < 0.5, 0.5–2 and > 2 mm), litter type (e.g., leaf, stem and root), climate zone (e.g., tropical and temperate), and ecosystem type (e.g., forest, grassland and wetland). Model selection analysis showed that background soil pH was the primary predictor driving litter decomposition in response to P addition. Main Conclusions Our results highlighted that P addition promoted the degradation of organic C, lignin, and cellulose and accelerated the process of litter decomposition. Moreover, the patterns and primary predictors (e.g., backgroud soil pH) are critical for accurately understanding how anthropogenic P input influences these processes.