基于遥感与地理信息数据的科尔沁沙地生态环境状况动态评价

科尔沁沙地处于蒙古、华北与兴安植物区系交汇处，是蒙古高原向东北平原的过渡区，具有丰富的生物多样性，属于典型农牧交错区，亦是东北平原的重要生态屏障。建国以来，受全球气候变化以及城镇化扩张、草原开垦及过度放牧等多重因素影响导致该区生态退化，生态系统服务功能下降。为此，利用遥感和地理信息数据，采用综合评估的方法，对近30年该区重大生态修复工程的实施过程及修复效果进行科学评估，具有重要的理论与实践意义。研究结果表明：1990、2000、2010、2015、2020年该区生态环境指数分别为75.19、70.20、73.51、74.27和74.7,其生态环境的变化可大致分为3个阶段，即退化期(1990—2000年)、恢复期(2000—2010年)和稳定期(2010—2020年)。2000年后，多项国家重点生态工程的实施对生态环境的改善具有明显推动作用，即科尔沁沙地生态环保工程的保护成效显著。城市化进程加快和水资源短缺是该区生态环境改善的主要制约因素，生态保护和地下水资源利用工程的实施仍需加强。研究可为科尔沁沙地生态保护和修复提供科学依据和实践参考。

Dynamic evaluation of ecological environment in Horqin sandy land based on remote sensing and geographic information data

Horqin Sandy Land, as the transition zone from the Mongolian Plateau to the Northeast Plain, is located at the intersection of Mongolian, North China and Xing''an flora, with rich biodiversity. It is a typical agriculture-pastoral ecotone and an important ecological barrier in the Northeast Plain. Due to the influence of human factors such as urbanization expansion, grassland reclamation and overgrazing, the Horqin Sandy Land has faced with seriously ecological degradation and ecosystem servicesdecline since the founding of China.Therefore,using remote sensing and geographic information data,a scientific evaluationwas conducted to researchthe implementation process and restoration effect of major ecological restoration projects in last 30 yearsin the area, which had important theoretical and practical significance.Based on the evaluation method in Technical Criterion for Eco-environment Status Evaluation (HJ/T192-2015), the changes of ecological environment of Horqin Sandy Landwere evaluatedin 1990, 2000, 2010 2015and 2020. The results showed that ecological environment index was75.19, 70.20, 73.51, 74.27,and 74.7in 1990, 2000, 2010, 2015, and 2020, respectively. Eco-environmental changes of Horqin Sandy Landcan be divided into three stages:the degradation period during 1990-2000, the recovery period during 2000-2010, and the stable period during 2010-2020. Since 2000, several national ecological projects havebeen implementedinthe region. Consequently, although theEI decreased 4.99 from 1990 to 2000, it increased 4.5from 2000 to 2020. The changes of the EI indicated that the ecological environment protection projects of Horqin Sandy Land had achieved remarkable efficiency. Acceleration of urbanization and shortage of water resources were main restraining factors for the improvement of ecological environment in Horqin Sandy Land. Thus, it is necessary to carry out further ecological conservation projects and groundwater resources utilization engineering.This study could provide scientific basis and practical reference for ecological protection and restoration forHorqin Sandy Land.