摘要
CEVSA模型是一个基于生理生态过程模拟植物—土壤—大气系统能量交换和水碳氮耦合循环及其对环境变化响应和适应的机理模型,在区域和全球尺度上得到广泛应用,但缺乏在生态系统尺度上的验证。本研究对CEVSA模型中碳循环关键过程的定量表达进行了重要改进:将模型的模拟时间步长由“旬”改为“日”;增加了物候参数化的子程序;调整了生物量的分配方案;基于碳平衡模拟叶面积指数的季节动态等。分别使用改进前后的CEVSA模型模拟了3类典型森林生态系统碳交换的季节动态,模拟的结果与通量观测进行了比较分析。结果表明,改进后的CEVSA模型能更好地模拟不同类型森林生态系统碳交换的季节动态,但在不同生态系统的不同时段,模型模拟的结果与通量观测相比还有一定的偏差,模型在碳交换关键过程对环境变化的响应和适应,尤其是针叶林光合作用对温度变化的响应和适应,以及生态系统对高温和水分亏缺的响应和适应等方面的模拟还需要进一步的改进和验证。
The model of Carbon Exchange in the Vegetation-Soil-Atmosphere （CEVSA） is an ecosystem mechanical model to simulate energy transfers and water, carbon and nitrogen cycles based on ecophysiological processes. It has been widely used at the scales of regional and global; however, the description of water and carbon fluxes have not yet been evaluated and validated at ecosystem scale. The revised CEVSA model incorporates several significant improvements over the previous version of CEVSA. Using data from eddy covariance measurements in three different forest ecosystems, which represent the temperate mixed forest, temperate deciduous forest and subtropical coniferous forest, respectively, we tested and evaluated the previous and revised CEVSA model. The revised and previous model both can simulate the seasonal variation of carbon exchange in different forest ecosystem, and the revised model simulated much better the temporal variation and magnitude of carbon exchange than the previous model did. However, systematic errors in flux simulation were also identified for particular time of season in different ecosystems. The present study shows that the revised CEVSA model can simulate the seasonal pattern and magnitude of CO2 fluxes, but further improvement in calibrating the model simulation, especially in the responses and adaptability of photosynthesis and respiration to environment change, is required.
出处
《地球科学进展》
CAS
CSCD
北大核心
2007年第3期313-321,共9页
Advances in Earth Science
基金
中国科学院创新团队国际合作伙伴计划"人类活动与生态系统变化"(编号:CXTD-Z2005-1)
国家自然科学基金重大项目"生态系统水碳氮循环过程对全球变化的响应与适应机制"(编号:30590381)
国家重点基础研究发展计划项目"中国陆地生态系统碳循环及其驱动机制研究"(编号:G2002CB412507)共同资助
作者简介
顾峰雪（1974-），女，江苏徐州人，在读博士生，主要从事生态系统过程与全球变化研究，E-mail：gufx@igsnrr.ac.cn
