环境因子对森林净生态系统生产力的影响

净生态系统生产力(net ecosystem production,NEP)是生态系统净的碳积累速率,可以指示生态系统碳汇/碳源的状态,当NEP为正值时指征生态系统为碳汇,反之则为碳源。在全球环境变化背景下,NEP已作为生态系统碳循环的核心概念被深入研究。本文以NEP为出发点,综述了5个主要非生物环境因子(水分、温度、氮沉降、大气CO2浓度增加和时空尺度)对森林生态系统NEP的影响。从文献分析表明NEP受生态系统本身性质和各环境影响因子及其之间相互作用的调控。本文最后指出,合理运用Meta分析、生态学联网研究、设计和开展长期观测、多尺度与多因子的科学试验在未来研究中的重要性和必要性,相关研究的开展将有利于全面理解和正确评估环境因子对净生态系统生产力的影响,对研究和预测全球变化对陆地生态系统碳循环的影响具有重要意义。

Effects of Abiotic Factors on Forest Net Ecosystem Production

Net ecosystem production （NEP） is the rate of net carbon accumulation in an ecosystem, and can be used to indicate the status of carbon sinks or sources. When NEP is positive, it indicates that the ecosystem is a carbon sink; when it is negative, it indicates that it is a carbon source. Under global environmental change, NEP has been considered as a central concept in ecosystem carbon cycles. This paper assessed the effects of abiotic factors such as water dynamics, temperature change, nitrogen deposition, atmospheric CO2 enrichment and temporal-spatial scale on forest NEP in recent years. Our review showed that NEP is not only affected by ecosystem characteristics, but also regulated by environmental factors and their interactions. Future research challenges include： （1）furthering meta- analyses when examining one environmental factor; （2）developing ecological networks for examining environmental effects at regional to global scale; and （3）conducting experiments with long-term, multi-scales and multi-factors. Fundamentally, more studies are needed to investigate and predict the impacts of global environmental change on terrestrial carbon cycling.