定量评估区域和不同类型生态系统的碳收支,可以为科学预测气候变化、服务于减缓和适应气候变化的区域碳管理提供科学依据,是生态系统与全球变化科学研究的重要科技问题。虽然区域碳收支的定量评估和认证还很难用当前的各种直接观测和评估方法来精确实现,但是,近年来这方面做了很多研究工作,也取得了一定进展。为此,本文综述了陆地生态系统碳收支的观测技术体系,重点分析区域尺度陆地生态系统碳收支评估方法及其不确定性。分析结果认为,为了定量认证中国区域的陆地生态系统、主要行业以及与碳汇相关项目的碳汇功能及其时空格局,急需采用"多尺度观测、多方法印证、多过程融合、跨尺度认知和跨尺度模拟"的研究思路,构建基于野外台站的碳循环及其通量的观测和实验研究网络、发展地面站点-陆地样带-生态网络与卫星和航空观测结合的多尺度观测系统,发展观测数据-生态过程模型-卫星遥感模型-GIS空间分析系统。同时,本文指出:生态系统碳-氮-水循环间的耦合机制及其对碳源汇时空格局影响研究必将成为生态系统碳循环及其区域碳收支评估和定量认证科学研究的重要发展方向和新的研究热点。
Quantitative assessment of carbon budgets at regional scale or in different ecosystems is an important scientific issue in the field of ecosystem and global change,which can provide scientific basis for forecasting climate change and regional carbon management serving for mitigation and adaptation to climate change.Though assessment and authentication of regional carbon budgets could not be fulfilled precisely using current measurements and evaluation methods,many progresses had been made.In this paper,we reviewed the observation technique systems,especially the methods and their uncertainties in evaluating regional carbon budget.To evaluate the carbon sink function of ecosystems,main industries,and projects related to carbon sink and their spatiotemporal patterns quantitatively,it is urgent to build an observation and experiment network based on field platforms and to develop a multi-scale observation system comprised by field platforms,terrestrial transects and ecological networks combined with satellites and aviation observations.The system based on observation data,ecological process model,remote sensing model and GIS spatial analysis is also needed to be built.These systems should be under the guideline of multi-scale observation,multi-method confirmation,multi-process fusion,across-scale cognition and simulation.Meanwhile,cycles of carbon,nitrogen and water in terrestrial ecosystems are coupled by various biological processes,while the knowledge of the coupling mechanisms and their influences on the spatiotemporal patterns of carbon source or sink was limited,so it will be an important aspect and new research hot in the research of ecosystem C cycle and regional carbon budget assessment and authentication.