Effects of leaf age and canopy structure on gross ecosystem production in a subtropical evergreen Chinese fir forest
Effects of leaf age and canopy structure on gross ecosystem production in a subtropical evergreen Chinese fir forest
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亚热带常绿杉木林叶龄和冠层结构对生态系统总生产的影响
DOI：
10.1016/j.agrformet.2021.108618
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发表时间：
2021-11
影响因子：
6.2
通讯作者：
Jie Jiang
中科院分区：
文献类型：
--
作者：
Qiaoli Wu;Conghe Song;Jinling Song;Jindi Wang;Shaoyuan Chen;Lei Yang;Wenhua Xiang;Zhonghui Zhao;Jie Jiang
尽管大规模获取 Rubisco 羧化 (V c max) 季节性最大速率的技术取得了进步，但如果没有大规模的现场测量，控制 V c max 时间动态的因素在很大程度上是未知的。此外，最先进的基于过程的陆地生态系统模型没有考虑复杂的冠层结构来估计植被的辐射拦截。这两者都可能导致生态系统总产量（GEP）估算的不确定性。在这里，我们通过将 Farquhar 光合作用模型与基于几何光学和辐射传递 (GORT) 理论的两叶（阳光照射和阴影）冠层辐射拦截模型相结合，研究了叶龄和冠层结构对 GEP 的各自和综合影响。我们观察到新叶的 V cm a x 比成熟叶高约 34.4%。考虑到新叶扩张引起的 V c m a x 的季节性动态，在 8 天时间尺度的生长季节中，建模的 GEP 与涡度协方差 (EC) 得出的平均偏差从-8% 减少到-1%，相关性稍高（从 0.9 到 0.92），均方根误差降低（从 6.0 g C m− 2 8d− 1 减少到 3.9 g C m− 2 8d− 1）。最重要的是，生长季节期间新叶扩张和冠层间隙的总影响为+ 322 g C m− 2 yr− 1 和-114 g C m− 2 yr− 1，分别约为总GEP的22.5%和8.1%。因此，在开发稳健的陆地生态系统模型时，考虑叶龄和冠层结构非常重要。我们强调，V c max 季节性和现实的冠层辐射拦截模拟对于准确估计常绿森林冠层 GEP 至关重要。
Despite the advances in technologies to derive the maximum rate of Rubisco carboxylation (V c m a x) seasonality at large-scale, factors controlling the temporal dynamics of V c m a x is largely unknown without extensive field measurements at stand scale. In addition, state-of-the-art process-based terrestrial ecosystem models had not accounted the complex canopy structure for estimating radiation interception by vegetation. Both of which could lead to uncertainties in gross ecosystem production (GEP) estimations. Here, we examined the respective and combined effects of leaf age and canopy structure on GEP by integrating the Farquhar photosynthesis model with a two-leaf (sunlit and shaded) canopy radiation interception model based on the Geometric Optical and Radiative Transfer (GORT) theory. We observed that the V c m a x of new leaves was approximately 34.4% higher than that of mature leaves. Considering the seasonal dynamics of V c m a x caused by new leaf expansion, the average bias between the modeled GEP and that derived from the eddy covariance (EC) in the growing season at 8-day temporal scale was reduced from-8% to-1%, with slightly higher correlation (from 0.9 to 0.92) and reduction in root mean squared error (from 6.0 to 3.9 g C m− 2 8d− 1). Most importantly, the total effect of new leaf expansion and canopy gaps during the growing season was+ 322 g C m− 2 yr− 1 and-114 g C m− 2 yr− 1, which was approximately 22.5% and 8.1% of the total GEP, respectively. Thus, it is important to consider both leaf age and canopy structure when developing a robust terrestrial ecosystem model. We highlighted that V c m a x seasonality and realistic canopy radiation interception simulation are critical for accurate estimation of canopy GEP for evergreen forests.
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DOI：
10.3390/rs10020262
发表时间：
2018-02
期刊：
Remote. Sens.
影响因子：
--
作者：
Qiaoli Wu;C. Song;Jinling Song;Jindi Wang;Shaoyuan Chen;Bo Yu
通讯作者：
Qiaoli Wu;C. Song;Jinling Song;Jindi Wang;Shaoyuan Chen;Bo Yu
影响因子：
13.5
作者：
Yulong Zhang;C. Song;L. Band;G. Sun;Junxiang Li
通讯作者：
Yulong Zhang;C. Song;L. Band;G. Sun;Junxiang Li
DOI：
10.1016/b978-0-12-332850-2.50009-8
发表时间：
1982
期刊：
--
影响因子：
--
作者：
J. Norman
通讯作者：
J. Norman
影响因子：
4.1
作者：
Congrong Li;Jinling Song;Jindi Wang
通讯作者：
Jindi Wang
影响因子：
7.3
作者：
K. Wilson;D. Baldocchi;P. Hanson
通讯作者：
K. Wilson;D. Baldocchi;P. Hanson