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森林生态系统是人类生存繁衍和可持续发展不可缺少的组成部分。森林死亡是森林衰退的主要表现形式之一。近年来全球升温导致全球范围内尤其半干旱区极端气候频发,造成大面积森林死亡,对植物群落、生态功能、生态系统服务等产生重要影响。不同地区不同类型的森林死亡呈现出不同的时空格局及驱动机制。研究森林死亡时空动态及其对气候变化的响应对改善生态环境、促进森林生态恢复具有十分重要的意义。基于样地网络实地调查与遥感分析是进行森林死亡动态监测的主要手段。本研究对森林死亡的定义、生态影响和监测方法以及气候变化与森林死亡之间的关系等研究进行了系统的总结,结果发现未来需加强以下几个方面的研究:第一,深入分析干旱胁迫的时空特征,厘清干旱的季节性特征和融雪时间的变化等,并加强生物群系之间及其与气候变化之间关系的研究和控制实验的研究,以揭示干旱和升温对森林死亡的作用机制。第二,研究干旱胁迫下树木的碳储存与利用机制以及生态水文过程等现象,深入探讨两者的耦合机理,并增加对大气CO_2、氮沉降、臭氧和干旱动态变化以及植物生产力、树液流动、菌根作用等的分析,构建和完善基于过程的树木死亡机理模型,以便能更准确地预测未来森林死亡事件的发生。第三,加强国际合作,构建全球范围内的数据体系,为大尺度上的森林死亡及其对气候变化的响应研究提供数据和技术支持。
Forest ecosystems are an essential part of human existence and reproduction and sustainable development. Forest deaths are one of the major manifestations of forest decline. In recent years, global warming has led to extreme global climate extremes, especially in semi-arid areas, resulting in large-scale forest deaths and significant impacts on plant communities, ecological functions and ecosystem services. Different types of forest deaths in different regions show different spatial and temporal patterns and their driving mechanisms. Studying the spatio-temporal dynamics of forest death and its response to climate change is of great significance to improving the ecological environment and promoting forest ecological restoration. Field survey and remote sensing analysis based on plots of plots are the main means of dynamic monitoring of forest deaths. The study summarizes systematically the definition of forest death, ecological impact and monitoring methods, and the relationship between climate change and forest death. The results show that the following aspects need to be strengthened in the future: First, in-depth analysis of drought stress To clarify seasonal characteristics of drought and changes in snowmelt time, and to strengthen studies on control and research of the relationship between biomes and climate change to reveal the effects of drought and warming on forest mortality mechanism. Secondly, to study the mechanism of carbon storage and utilization under drought stress and the ecohydrological processes, and to further explore the coupling mechanism between the two and to increase the effects of atmospheric CO 2, nitrogen deposition, dynamic changes of ozone and drought, plant productivity, , Mycorrhizal function analysis, construction and improvement of process-based tree death mechanism model in order to be able to more accurately predict the future occurrence of forest deaths. Third, to strengthen international cooperation and establish a worldwide data system to provide data and technical support for research on large-scale forest deaths and their response to climate change.