中国区域复杂而多样的地貌类型，加之气候、群落组成、立地条件、管理措施等多种因素的影响，生态系统净生产力NEP呈现出显著的时空变异性。揭示这一时空变异特征及其潜在调控机制对于准确预测区域碳收支变化至关重要。本研究拟以中国通量观测网ChinaFLUX观测台站（4个森林站，3个草地站，1个农田站）为依托，整合分析过去10年（2005-2015年）典型生态系统的NEP年际变异特征、多年平均碳收支状况及生态系统间的差异，解析生产力(GPP)和利用率(RE/GPP)两个关键参数对NEP时空变异的调控作用。在此基础上，选取3个不同类型生态系统（森林、草地、农田）开展气候监测、生物量调查、植被属性观测及氮沉降观测实验，分别揭示GPP和RE/GPP时空变异的影响因素及调控机理，最终阐明NEP时空变异的形成机制，以期为我国陆地生态系统碳收支的变化趋势预测提供参考，也为我国减缓气候变化的区域碳管理提供政策依据。

Under the complex influences of topography, climate, community composition, site condition and managements, the net ecosystem productivity (NEP) of China exhibit significant variations at the temporal and spatial scales. Understanding the temporal-spatial patterns and the underlying regulating mechanisms is important to accurately predict the future regional carbon budget change. This study synthesizes observational stations (4 forests, 3 grasslands and 1 croplands) of Chinese flux observation and research network (ChinaFLUX), to explore the interannual variations of typical ecosystems NEP over the past 10 years (2005-2015), and assess the carbon budget and its difference between ecosystems. Regulations of gross productivity (GPP) and carbon use efficiency (RE/GPP) on NEP are further analyzed. Moreover, we perform continuous environmental observation, biomass survey, phenology observation, plant and soil properties measurement, and nitrogen deposition collection at 3 different type ecosystems (1 forest, grassland and cropland respectively), to reveal the temporal-spatial variations of GPP and RE/GPP and their influence factors, and to finally explore the regulating mechanisms for the temporal-spatial variation of NEP. This study is expected to provide knowledge for predicting the future trend of China's terrestrial ecosystem carbon budget, and for policy making in regional carbon management and climate change mitigation in China.