土壤激发效应的机制及影响因素研究进展

Mechanisms and Influencing Factors of Soil Priming Effect:A Review

激发效应在全球土壤中广泛存在,但方向和强度具有极大的分异性。针对土壤激发效应的机制和影响因素进行综述,总结目前较为认可的机制,包括底物优先利用、共代谢、养分挖掘和化学计量分解假说等。探究影响激发效应的方向和强度的生物和非生物的因素,将其划分为外源有机物的性质、土壤理化特性、分解者和环境条件四大类。未来应进一步改进研究方法,以便模拟真实环境下激发效应的发生过程,并重点关注土层、时间等的变化对激发效应强度和方向的影响,为改进土壤碳模型提供数据支持。

Globally,soil priming effect(PE)is regarded as a widespread process,but with equivocal directions and intensity.Multiple hypotheses of PE mechanisms were summarized,including preferential substrate utilization,co-metabolism,nutrient mining,and stoichiometric decomposition.This review also discussed abiotic and biotic factors that may regulate PE direction and intensity,which could be divided into properties of exogenous substrates,soil physicochemical characteristics,decomposers,and environmental conditions.Future researches should improve the experimental methods of simulating priming effect in natural conditions,and pay more attention to the alteration of PE direction and intensity along soil profile or time period to improve soil carbon models.