While these studies provide very helpful information for our understanding of control on litter decomposition, the results are mostly site specific, based on small-scale laboratory and field experiments, and difficult to extrapolate to the large spatial scales. 2000) and (iv) geographical variables such as LAT and altitude (ALT) ( Aerts 1997 ( Silver and Miya 2001). 1985) and lignin:N ratio (LIGN:N) ( Aerts 1997 Waring and Schlesinger 1985) (iii) vegetation and litter types ( Gholz et al. nitrogen content (N) ( Yavitt and Fahey 1986), carbon:nitrogen ratio (C:N) (Edmonds 1980 Berg and Ekbohm 1991), lignin content (LIGN) ( Gholz et al. 1990 Meentemeyer and Berg 1986 Moore 1986 O'Neill et al. Factors that regulate k values have been identified as (i) climatic factors such as mean annual temperature (MAT), mean annual precipitation (MAP) and annual actual evapotranspiration (AET) ( Aerts 1997 Berg et al. Litter decomposition of plant species has been studied for decades, especially at site levels (e.g. So far, it is still not entirely clear how k values distribute at the large spatial scale and, more importantly, which factors are critical in controlling the litter decomposition globally. To accurately predict the amount of C released through the litter decomposition, this variability must be accountable and well documented ( Liski et al. One noteworthy feature of litter decomposition is the variability of litter decomposition rate ( k) among ecosystems and under different climatic conditions. Litter decomposition plays an important role in carbon (C) cycling in terrestrial ecosystems ( Aerts 2006 Field et al. The global-scale empirical relationships developed here are useful for a better understanding and modeling of the effects of litter quality and climatic factors on litter decomposition rates.Ĭlimatic factors, geographic factors, litter decomposition rate, litter quality, path analysis, terrestrial ecosystems Introduction This data synthesis revealed significant relationships between litter decomposition rates and the combination of climatic factor (MAT) and litter quality (C:N, TN). These results indicate that litter quality is the most important direct regulator of litter decomposition at the global scale. The combination of LAT, MAT, C:N and TN accounted for 87.54% of the variation in the litter decomposition rates. However, the combination of total nutrient (TN) elements and C:N accounted for 70.2% of the variation in the litter decomposition rates. Single factor such as climate, litter quality and geographic variable could not explain litter decomposition rates well. The k values tended to decrease with latitude (LAT) and lignin content (LIGN) of litter but increased with temperature, precipitation and nutrient concentrations at the large spatial scale.