全球变化与中国东北样带(NECT)

GLOBAL CHANGE AND WATER-DRIVEN IGBP-NECT,NORTHEAST CHINA

全球变化陆地样带是从机理上理解陆地生态系统对全球变化的响应 ,预测全球变化对陆地生态系统的可能影响 ,实现预警、调节和减小全球变化不良影响 ,科学地规划和管理陆地生态系统的有效研究平台。在介绍国际全球变化陆地样带提出的背景与选定标准、中国东北样带的位置与特征的基础上 ,较系统地总结了近年来中国东北样带的研究进展 :建立了用于模型发展和比较的不同时间和空间尺度的中国东北样带数据集 ,从机理上初步探讨了全球变化对于森林、草甸草原和典型草原的可能影响 ,发展了用于古植被气候重建的植物种与表土花粉类型的定量关系模型、多尺度耦合的羊草草原生态系统动态模型和基于林窗原理的森林生态系统动态模型 ,并对全球变化对中国东北样带的影响进行了初步评估 ,进而针对我国作为发展中国家 ,财力有限的特点 ,提出未来中国东北样带研究拟充分利用我国特殊的生态环境与区域特色 ,围绕“生态过程与生态安全及其对全球变化的响应与反馈”这一关键科学问题 ,做出一些在国际上既有显示度 ,又服务于我国社会经济可持续发展的研究成果。

IGBP terrestrial ecosystem is an effective platform for global change studies, in order to understand how terrestrial ecosystems will respond to global change, to predict and evaluate the possible effects of global change, and to ensure the sustainable development of our life-supporting system. First of all, the background of IGBP terrestrial transect and its selection standards as well as the allocation and characteristics of Northeast China Transect (NECT) are described, and then the advance in NECT during recent years is presented systematically. The achievements related to NECT include: (1) the development of NECT database; (2) primary elucidation of the responsible mechanisms of typical terrestrial ecosystems (forest, meadow steppe and typical steppe) along NECT to global change; (3) developments of quantitative relationships between vegetation and several pollen taxa in surface soil for past global change studies, multi-scale coupling ecosystem dynamic model of Leymus chinensis grassland, and gap-based forest ecosystem dynamic models; and (4) preliminary prediction on the possible effects of global change on NECT. Finally, considering the financial and man-power conditions of China and its special eco-environment, the authors emphasize that the future NECT study should pay more attention to the key science problem, i.e., “the ecological processes/ecological security and their responses to global change”.