喀斯特石生苔藓生物岩溶侵蚀机理及其碳汇效应

China's response to climate change policies and action (2011) by the state council issued a white paper and comprehensive treatment engineering carbon significantly increased heavy assessment requirements, founded in 2007, in south China karst rocky desertification areas, aimed at the problem of the basic theory of biokarstification and karst ecosystem carbon sink research. systematics and biokarst principle theory are applied, further study on the interaction of physiological metabolism and saxicolous moss,and it's carbon sink effect. Different saxicolous mosses, research objects and research is a key step of photosynthesis physiological use carbon dioxide and water. Interaction of the overall concept is introduced with air-rock-soil-water-biological, based on open CO2-H2O-Carbonate karst dynamic system of joint point of view. Environmental factors and physiological metabolism of saxicolous mosses was discussed, and driving action of the metabolic process of limestone dissolution(photosynthetic rate, respiration intensity, carbonic anhydrase activity, water use efficiency, and organic acid secretion, and so on).The erosion mechanism of biokarst saxicolous mosses and quantitative carbon sink effect are explanation, from point to surface research of coupling relationship between the biological carbon sink and the karst carbon sink,and precise estimate carbon sinks, as new evidence provided the so-called "carbon missing sink" phenomenon of the lack of research in the global carbon cycle.The foundation will play an important role to the theory of ecological restoration and reconstruction of karst region, carbon cycle of biosphere under global changes, and also to the science base of the climate change and greenhouse gas emissions country provides to countermeasure and the reference.

针对当前生物岩溶的主要理论空白和热点问题与 2007 年启动的中国南方喀斯特地区石漠化综合治理工程的固碳增汇评估工作的重大需求，瞄准岩溶生态系统生物岩溶作用和碳汇研究的基础理论问题，应用系统学理论和生物岩溶学原理，深入研究石生苔藓生理代谢与石灰岩的相互作用及其产生的碳汇效应，以CO2和水分的生理利用为中心环节，引入水-岩-土-气-生物相互作用的整体概念，运用 “CO2-水-碳酸盐”三相耦联开放岩溶动力系统观点，探讨环境因子对石生苔藓生理代谢的影响，生命代谢过程对石灰岩溶蚀的驱动作用，明确石生苔藓的生物岩溶侵蚀机理并初步估算其产生的碳汇，其成果可为喀斯特生态环境的重建、全球变化下的生物圈碳循环和碳汇研究提供基础的参考资料。

石漠化石生苔藓在喀斯特植被演替前期具有重要的生态作用，分析石生苔藓代谢产物的岩溶作用活性和驱动作用，并积极探索不同环境胁迫下其活性的变化及其岩溶作用的意义，为岩溶地区生态恢复与重建提供理论依据。通过生态学调查——代谢活性分析——模拟试验相结合。研究发现：普定石漠化区域共有石生藓类植物8科24属54种，其中丛藓科和灰藓科为优势科，扭口藓属、真藓属、曲柄藓属、拟合睫藓属和细喙藓属为优势属。石生藓类及其基部土壤的碳酸酐酶(CA)活性存在一定的差异；土柱模拟实验石生植物生理代谢均对石灰岩有较强的溶蚀作用，4种植物CA总体表现出先略降，然后升高，最后趋于平稳的趋势；淋出液中有机酸中酒石酸的含量变化呈递减趋势，pH值呈上升趋势；电导率呈下降趋势，石生苔藓类植物对石灰岩有明显的酶促和酸促溶蚀驱动作用。3种石生藓类RWC与qN负相关，与Fv/Fm、Yield、ETR、qP呈正相关关系，复水后各荧光参数在轻中度胁迫下能恢复到正常水平，而重度胁迫较难恢复到对照水平，光合过程石生藓类对水分干/湿态循环迅速转换具有较强的生理适应能力。水分利用效率（WUE）随胁迫程度的增加不断下降，复水后WUE有一定程度的恢复。不同石生苔藓植物的水分生理随胁迫处理的时间变化而变化，水分生态适应性存在种间差异；成土和保土功能各异；不同石生植物生理代谢对石灰岩溶蚀的程度和规律明显不同。