千烟洲马尾松人工林生态系统的碳循环模拟及模型参数的

千烟洲马尾松人工林生态系统的碳循环模拟及模型参数的敏感性分析*

王　媛1

　张　娜

1**

　于贵瑞

2

(1中国科学院研究生院资源与环境学院,北京100049;

2

中国科学院地理资源与环境研究所,北京100101)

摘　要　应用改进后的碳水循环过程模型 景观尺度生态系统生产力过程模型(ecosystem productivity process model for landscape ,EPPML )模拟了2003和2004年千烟洲马尾松人工林生态系统的碳循环过程,并对模型参数的敏感性进行了分析.结果表明:EPPML 可用于模拟千烟洲马尾松人工林的碳循环过程,不仅总初级生产力(GPP )㊁生态系统净生产力(NEP )和生态系统总呼吸(R e )的年总值和季节变化与实测值十分吻合,而且也能反映极端天气对碳流的重要影响;千烟洲马尾松人工林生态系统具有较强的净碳吸收能力,但2003年生长最旺季的高温和重旱天气的耦合作用使其碳吸收能力明显低于2004年,2003和2004年平均NEP 分别为481.8和516.6g C ㊃m -2㊃a -1;马尾松生长初期的光照㊁生长旺期的干旱㊁生长末期的降水量是改变碳循环季节变化的关键气象条件;自养呼吸(R a )与净初级生产力(NPP )的季节进程一致;异养呼吸(R h )在年尺度上受土壤温度控制,而在月尺度上则受土壤含水量波动的影响;在生长季的丰水期,土壤含水量越大,R h 越小;而在生长季的枯水期,前两个月的降雨量越大,R h 也越大.EPPML 参数中,25℃时的最大RuBP 羧化速率(V m25)㊁比叶面积(SLA )㊁最大叶N 含量(LN m )㊁平均叶含N 量(LN )㊁生物量与碳的转换率(C /B )对年NEP 的影响最大;不同碳循环过程变量对敏感参数变化的响应也不尽相同,其中,V m25和LN 的增加能有效促进植物的碳吸收和呼吸;LN /LN m 越小,对碳吸收和呼吸的抑制作用越强;C /B 和SLA 的增大会促进碳吸收,抑制呼吸.将全年区分为生长季与非生长季时得到的最敏感参数的结论与全年不尽相同.

关键词　碳循环　基于过程的模型　异常天气　生态系统净生产力　土壤异养呼吸*国家自然科学基金国际(地区)合作交流项目(30721140307)和国家自然科学基金项目(30870430,30500076)资助.**通讯作者.E⁃mail:zhangna@ 2010⁃01⁃29收稿,2010⁃05⁃04接受.

文章编号　1001-9332(2010)07-1656-11　中图分类号　Q948.1　文献标识码　A

Simulation of carbon cycle in Qianyanzhou artificial masson pine forest ecosystem and sensi⁃tivity analysis of model parameters.WANG Yuan 1,ZHANG Na 1,YU Gui⁃rui 2(1College of Re⁃source and Environment ,Graduate University of Chinese Academy of Sciences ,Beijing 100049,Chi⁃na ;2Institute of Geographic Sciences and Natural Resources Research ,Chinese Academy of Sciences ,Beijing 100101,China ).⁃Chin.J.Appl.Ecol .,2010,21(7):1656-1666.

Abstract :By using modified carbon⁃water cycle model EPPML (ecosystem productivity process model for landscape),the carbon absorption and respiration in Qianyanzhou artificial masson pine forest ecosystem in 2003and 2004were simulated,and the sensitivity of the model parameters was analyzed.The results showed that EPPML could effectively simulate the carbon cycle process of this ecosystem.The simulated annual values and the seasonal variations of gross primary productivity (GPP),net ecosystem productivity (NEP),and ecosystem respiration (R e )not only fitted well with the measured data,but also reflected the major impacts of extreme weather on carbon flows.The artificial masson pine forest ecosystem in Qianyanzhou was a strong carbon sink in both 2003and 2004.Due to the coupling of high temperature and severe drought in the growth season in 2003,the carbon absorption in 2003was lower than that in 2004.The annual NEP in 2003and 2004was 481.8and 516.6g C㊃m -2㊃a -1,respectively.The key climatic factors giving important impacts on the seasonal variations of carbon cycle were solar radiation during early growth season,

应用生态学报　2010年7月　第21卷　第7期 Chinese Journal of Applied Ecology,Jul.2010,21(7):1656-1666