Forest soil autotrophic and heterotrophic respiration under different mycorrhizal strategies and their responses to temperature and precipitation

Mycorrhizal symbiosis between plant roots and mycorrhizal fungi are almost ubiquitous. These interactions contribute a largely to soil autotrophic respiration (R_A), influence soil heterotrophic respiration (R_H) and respond strongly to such climatic changes as temperature and precipitation. The aim of the present study was to explore how variation of temperature and precipitation influence R_A and R_H in global forest ecosystems that are classified by the mycorrhizal type of the dominant plants. The results show slight variation for R_A and significant change for R_H among different mycorrhizal strategy types. In forests with predominating arbuscular mycorrhiza (AM) the R_A and R_H are trifling higher than in non-AM type forests. The responses of R_A and R_H to temperature and precipitation were highly variable among different mycorrhizal strategies. For example, the changes of R_A and R_H are more dependent on precipitation than temperature in AM-forest, and temperature accounted more for their variations in forests of the other three mycorrhizal types. As far as we know, this study was the first to evaluate the influence of different mycorrhizal strategies on forest R_A and R_H and their response to temperature and precipitation.