顾及水热波动的内蒙古温带典型草原退化遥感监测研究

天然草地是我国最大的陆地生态系统，具有很高的生态和经济价值。然而在多种压力的影响下，草地退化成为我国北方草原面临的重要生态问题。针对遥感技术在区域草地退化监测研究中存在的主要问题（1）参考基准不易确定且未考虑其随时间变化在水热波动影响下的结构和功能状态；（2）退化评价指标单一化，难以兼顾生态系统结构和功能，尤其是在现有数据和技术条件下对区域退化指示物种的识别研究方面存在不足；本研究针对以上问题，以内蒙古锡林郭勒典型草原为研究区，采用遥感技术为主要监测方法，结合地面观测实验，在兼顾草地生态系统结构和功能的原则下，建立草地退化评价指标体系和退化评价的参考基准，在此基础上构建草地退化评价模型，分析草地退化的时空格局和退化特点，揭示草地退化时空演变规律，为国土空间规划、生态保护红线划定以及生态修复和区域生态安全的管理策略提供科学支持。

As the largest terrestrial ecosystem in China, grassland has significant ecological and economic values. However, due to multiple pressures, grassland degradation has become one crucial ecological problem in northern China. Remote sensing has been widely used in monitoring regional grassland degradation, however, a lot of challenges still exist. (1) The benchmark is difficult to be determined, which also doesn’t taken into account the temporal evolution of ecosystem structure and function state under the influence of water and heat fluctuations; (2) The evaluation indicators of grassland degradation are simple without considering ecosystem structure and functions, and based on available data and technologies, the studies on identifying indicator species for regional degradation are still much needed. To solve these problems, using a combination of remote sensing and field experiments, the vegetation community information will be extracted firstly, and then the indicator framework and benchmark for grassland degradation assessments will be established in Xilingol typical steppe, Inner Mongolia, by considering the structure and function of grassland ecosystems. Built on this, the model of grassland degradation assessments will be developed to further analyze the spatial and temporal variability of grassland degradation, explore the feedback mechanisms between grassland water-heat characteristics and degradation process, and thus reveal the temporal and spatial evolution of grassland degradation. This project is expected to provide scientific support for national spatial planning, ecological redline definition, ecosystem restoration, and regional ecological security management.