摘要
土壤无机CO_2通量(R_(io))是土壤CO_2通量(R_s)的重要组分,当前对土壤CO_2通量多基于完全来自有机源的假设,忽略无机过程影响的研究影响了碳循环过程及源汇评估的科学性和准确性。对R_(io)分离方法、特征与影响因素、形成机制等方面的研究进行了归纳总结。1)目前R_(io)分离方法主要有氯化汞灭菌法、加热法、高压灭菌法和^(13)C同位素法,不同的分离方法均具有一定的局限性,且研究成果之间的差异性较大降低了其可比性;2)特定研究地区R_(io)能够主导或暂时主导R_s的方向和大小,且变化特征受温度、含水量、pH、盐分和土壤粒径等因子的影响较大;3)形成机制主要有碳酸盐系统的溶解/沉淀、地下孔穴储藏与通风作用两大观点。在此基础上,针对今后的研究方向提出如下建议:1)探究更通用、简便和精确的分离措施并进行标准化,提高不同研究结果之间的可比性;2)进一步拓展研究的区域和范围,形成基于多生态系统的数据网络;3)深入探究土壤无机碳循环过程,为正确判定陆地生态系统碳源汇功能提供参考;4)加强对土壤R_(io)在生态系统中作用的研究,为寻找全球"碳失汇"提供更为科学的解释。
Soil inorganic CO2 flux (Rio) is an important part of soil CO2 flux (Rs). In current years, the estimation of Rs has been entirely based on the assumption of organic sources, however, the inorganic process of soil CO2 flux has been ignored, which seriously influences on the scientificity and precision of the estimation on CO2 flux. In this paper, some aspects on Rio were summarized including Rio partitioning measures, characteristics, influencing factors and the formation mechanisms. The current partitioning measures focused on Rio include HgCl2 sterilization, heating method, autoclaving and isotopic measurement of CO2-13C. All the four measures have their own shortcomings and the differences among the methods reducing the comparability of the study results. The Rio in specific research areas can entirely or partly dominate the magnitude and direction of Rs. Meanwhile, the change features of Rio are mainly influenced by temperature, moisture, pH, salt content and particle size of soil. There are two main explanations for the formation mechanisms of Rio: 1) dissolution/precipitation of carbonates; 2) subterranean cavity ventilation. Some research prospects based on current study references are proposed. Firstly, more partitioning measures should be explored to improve the universality, simplification and accuracy. Secondly, more study areas and scopes should be expanded to form the data network on account of multi ecosystems. Thirdly, further research on the cycle process of soil inorganic CO2 should be carried out for the determinations of carbon sink function in terrestrial ecosystems. Lastly, the effects of Rio in the ecosystem should be studied deeply to obtain the explanation for the search of global missing carbon sink.
出处
《生态科学》
CSCD
2017年第3期186-192,共7页
Ecological Science
基金
国家自然科学基金资助项目(41101080)
山东省自然科学基金资助项目(ZR2014DQ028
No.ZR2015DM004)
山东省高等学校科技计划资助项目(J12LC04)
青岛大学优秀研究生学位论文培育项目(YBPY2014008)
关键词
土壤无机CO2通量
分离方法
影响因素
机制
Soil inorganic CO2 flux
Partitioning measures
Influencing factors
Formation mechanism