干旱对草地生态系统影响研究进展

Progress of study on impact from drought on grassland ecosystem

在全球气候变化的背景下,干旱对生态系统的影响呈现复杂性、多过程性的特征,研究干旱对生态系统的损伤及其修复意义巨大,尤其是作为生态系统重要组成部分的草地生态系统。在对草地生态系统的干旱影响研究进展和研究方法进行总结的基础上,系统地梳理了草地生态系统生产力的基本概念和干旱影响草地生态系统的关键指标及其干旱下的变化过程,同时,总结了干旱对草地生态系统的影响机制与过程,并分别分析了干旱对GPP、TER、碳源汇等草地生态系统关键指标的影响过程。此外,干旱对草地生产力影响研究中常采用的试验观测、遥感监测和模型模拟等3种方法进行了总结和分析。在此基础上,围绕着当前干旱对草地生态系统的影响,研究所采用方法手段及其进展揭示了干旱对草地生态系统影响存在的问题。最终,凝练指出了改进模型和遥感监测的不确定性以加强干旱对生态系统损伤机理的定量化,揭示并建立干旱对生态系统影响系统评估框架,加强试验和模型模拟结合,走“数据-模型”融合的改进之路等4条干旱对草地生态系统影响研究的未来可能发展主要方向,相关研究可为干旱对草地生态系统影响研究提供参考。

Under the background of global climate change,the impact from drought on ecosystem exhibits the characteristics of complexity and multi-process,thus the study on the damage from drought and its restoration has a great significance,especially for the main component-grassland ecosystem of the overall ecosystem.On the basis of summarizing the progress of the study on the impact from drought on grassland ecosystem and its study methods,the basic concept of the productivity of grassland ecosystem and the key indexes of the impact from drought on grassland ecosystem as well as their changing processes under drought are systematically sorted out herein,meanwhile,the mechanism and process of the impact from drought on grassland ecosystem summarized and then the processes of the impact from drought on the key indexes,i.e.GDP,TER,carbon sink,etc.are analyzed respectively as well.Additionally,the relevant summarization and analysis are made on the three methods i.e.experimental observation,remote sensing monitoring and model simulation usually used in the study on the impact from drought on grassland productivity.On this basis,the problems currently existed in the study of the impact from drought on grassland ecosystem are revealed around the methods and means currently used in the study of the impact from drought on grassland ecosystem.Finally,it is concisely pointed out that the possible developing directions for the study on the impact from drought on grassland ecosystem in the days to come are to improve the uncertainties of the model and thee remote sensing monitoring for strengthening the quantification of the damage from drought on ecosystem,reveal and establish the assessment framework for the impact from drought on ecosystem,strengthen the combination between the experiment and the model simulation and go on the way of improving the integration of data-model,from which the relevant studied can provide some references for the study on the impact from drought on grassland ecosystem.