Soil Net N Mineralization Potential and Its Temperature Sensitivity Along a North‐South Forest Transect in the Eastern China

Abstract Soil net nitrogen (N) mineralization potential ( R min ) is a key indicator for predicting the capacity of available N supply for plant growth and ecosystem productivity. Thus, it is crucial to understand the spatial pattern and regulatory mechanisms of forest R min and its temperature sensitivity ( Q 10 ) under current global change scenarios. In this study, we determined the R min and its Q 10 value of soil samples collected from 18 forest ecosystems along a 5200‐km‐long north‐south forest transect in eastern China. We found significant differences in R min and its Q 10 values among different forest types. Tropical and subtropical forests had significantly higher R min values than temperate forests and cold temperate forests. In contrast, tropical and subtropical forests had the lowest Q 10 values followed by temperate forests and cold temperate forests. R min varied with mean annual precipitation, soil total carbon (C) and N, microbial biomass carbon (MBC) and the MBC to the microbial biomass nitrogen (MBN) ratio. The Q 10 value varied with the mean annual temperature (MAT), the MBC/MBN ratio, and aridity index. Overall, our results indicate that the Q 10 value of the R min is generally lower in warmer or wetter areas than in colder or drier areas along the north‐south forest transect in eastern China. Our results imply that the predicted global change may narrow the gaps in the R min between high‐ and low‐latitude forests or among forests with different humidity levels.