陆地生态系统与气候相互作用的研究进展

陆地生态系统与气候系统通过地面与大气之间能量平衡、水汽交换和生物地球化学循环相互作用,影响大气中温室气体浓度和气溶胶,继而影响气候变化。较系统分析总结了当代国际上陆地生态系统与气候相互作用的最新研究进展。首先介绍了陆地生态系统与气候相互作用的机制与过程,总结了陆地生态系统与气候相互作用研究的三个发展阶段,以及当代相互作用的过程模拟研究中三类主要的全球生态系统模型,即生物物理模型、生物地理模型和生物地球化学模型。并介绍了气候对生态系统变化的响应,即两种主要的反馈机制。最后,对未来的研究方向和重点作了分析。

PERSPECTIVE ON TERRESTRIAL ECOSYSTEM-CLIMATE INTERACTION

Terrestrial ecosystems and climatic systems influence each other through biophysical processes that involve the transfers of energy and water at the land surface and biogeochemical cycles that affect the concentrations of greenhouse gases and aerosols in the atmosphere. Studies of ecosystem climate interactions have evolved from uses of land surface parameterizations (LSPs) to sensitivity analysis of climatic responses to equilibrium ecosystem changes and to dynamic, interactive coupling of ecosystem and climatic processes. System modeling is the most important means to study ecosystem climate interactions. The global ecosystem models that have been used in the studies can be classified into biophysical, biogeography, and biogeochemical types. Ecosystem changes as a whole in the past have accelerated warming by increasing the emissions of CO 2, CH 4, and N 2O and reducing the regulation of vegetation to water cycling. Ecosystem negative feedbacks on climate have emerged with increases in CO 2 sequestration and the stabilization of CH 4 emissions, but continued increases in anthropogenic N 2 fixation may greatly enhance N 2O emissions. To quantify accurately the feedback effects requires investigations of the dynamic ecosystem climate interactions at seasonal and interannual scales. Future studies should focus on both developing integrated dynamic ecosystem models (IDEM) that can describing both functional and structural changes and coupling biophysical and biogeochemical processes and observing large scale, long term ecosystem changes. The observations are essential for deepening understanding of ecosystem climate interactions and validate global ecosystem models.