中文摘要：

土壤-植被-大气连续体（bPAC）是陆地水灭芋、生态芋布口全球变化领域的重要研究对象，其水碳循环过程及耦合机制是前沿性问题．稳定同位素技术示踪、整合和指示的特征有助于评估分析生态系统固碳和耗水情况．本文在简述稳定同位素应用原理和技术的基础上，重点阐释了基于稳定同位素光学技术的SPAC系统水碳交换研究进展，包括：在净碳通量中拆分光合与呼吸量，在蒸散通量中拆分蒸腾与蒸发量，以及在系统尺度上的水碳耦合研究．新兴的技术和方法实现了生态系统尺度上长期高频的同位素观测，但在测量精准度、生态系统呼吸拆分、非稳态模型适应性、尺度转换和水碳耦合机制等方面存在挑战．本文探讨了现有主要研究成果、局限性以及未来研究展望，以期对稳定同位素生态学领域的新研究和技术发展有所帮助．

英文摘要：

Soil-vegetation-atmosphere continuum （SPAC） is one of the important research objects in the field of terrestrial hydrology, ecology and global change. The process of water and carbon cyc- ling, and their coupling mechanism are frontier issues. With characteristics of tracing, integration and indication, stable isotope techniques contribute to the estimation of the relationship between carbon sequestration and water consumption in ecosystems. In this review, based on a brief intro- duction of stable isotope principles and techniques, the applications of stable isotope techniques to water and carbon exchange in SPAC using optical stable isotope techniques were mainly explained, including： partitioning of net carbon exchange into photosynthesis and respiration; partitioning of evapotranspiration into transpiration and evaporation; coupling of water and carbon cycle at the eco- system scale. Advanced techniques and methods provided long-term and high frequency measure- ments for isotope signals at the ecosystem scale, but the issues about the precision and accuracy for measurements, partitioning of ecosystem respiration, adaptability for models under non-steady state, scaling up, coupling mechanism of water and carbon cycles, were challenging. The main existing research findings, limitations and future research prospects were discussed, which might help new research and technology development in the field of stable isotope ecology.