Structure and parameter uncertainty in centennial projections of forest community structure and carbon cycling
Structure and parameter uncertainty in centennial projections of forest community structure and carbon cycling
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森林群落结构和碳循环百年预测的结构和参数不确定性
DOI：
10.1111/gcb.15164
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发表时间：
2020
影响因子：
11.6
通讯作者：
Gough, Christopher M.
中科院分区：
文献类型：
--
作者：
Shiklomanov, Alexey N.;Bond‐Lamberty, Ben;Atkins, Jeff W.;Gough, Christopher M.
几十年来，次生林的再生塑造了群落演替和生物地球化学，包括在上大湖地区。植被模型概括了我们对森林功能的理解，而模型能否重现多年代际演替模式是我们预测森林对未来变化响应能力的一个指标。我们测试了植被模型在林分更替干扰后100年森林再生期间模拟碳循环和群落组成的能力，并提出了以下问题：(a)哪些过程和参数对准确模拟中西部上游森林演替最重要？(b)模型结构与参数值对这些预测的相对重要性是什么？我们运行了生态系统人口统计学模型v2.2的集合，其中包含对光竞争重要的过程的不同表示。我们比较了结构和参数不确定性的大小，并评估了哪种子模型-参数组合最能再现观测到的碳通量和群落组成。平均而言，我们的模拟低估了100年后观测到的净初级生产力（NPP）和叶面积指数（LAI），并预测了单一植物功能类型（PFT）的完全优势。在4000次模拟中，只有9次落在NPP和LAI的观测范围内，但这些模拟预测了早期硬木或松木pft的完全优势，这是不切实际的。另一组7个模拟在生态学上是合理的，但观测到的NPP和LAI低于预测。参数不确定度大；NPP和LAI介于平均值的~0% ~ ~ ~ 200%之间，任何PFT都可能成为主导。对预测NPP的不确定性贡献最大的两个参数是植物-土壤水导率和生长呼吸，这两个参数都是不可观测的经验系数。我们得出的结论是：(a)参数的不确定性比结构的不确定性更重要，至少对于中西部北部森林的ED‐2.2来说是这样；(b)在没有物理上不现实的参数的情况下准确地模拟生产力和植物群落组成对人口统计学植被模型来说仍然是一个挑战。
Secondary forest regrowth shapes community succession and biogeochemistry for decades, including in the Upper Great Lakes region. Vegetation models encapsulate our understanding of forest function, and whether models can reproduce multi‐decadal succession patterns is an indication of our ability to predict forest responses to future change. We test the ability of a vegetation model to simulate C cycling and community composition during 100 years of forest regrowth following stand‐replacing disturbance, asking (a) Which processes and parameters are most important to accurately model Upper Midwest forest succession? (b) What is the relative importance of model structure versus parameter values to these predictions? We ran ensembles of the Ecosystem Demography model v2.2 with different representations of processes important to competition for light. We compared the magnitude of structural and parameter uncertainty and assessed which sub‐model–parameter combinations best reproduced observed C fluxes and community composition. On average, our simulations underestimated observed net primary productivity (NPP) and leaf area index (LAI) after 100 years and predicted complete dominance by a single plant functional type (PFT). Out of 4,000 simulations, only nine fell within the observed range of both NPP and LAI, but these predicted unrealistically complete dominance by either early hardwood or pine PFTs. A different set of seven simulations were ecologically plausible but under‐predicted observed NPP and LAI. Parameter uncertainty was large; NPP and LAI ranged from ~0% to >200% of their mean value, and any PFT could become dominant. The two parameters that contributed most to uncertainty in predicted NPP were plant–soil water conductance and growth respiration, both unobservable empirical coefficients. We conclude that (a) parameter uncertainty is more important than structural uncertainty, at least for ED‐2.2 in Upper Midwest forests and (b) simulating both productivity and plant community composition accurately without physically unrealistic parameters remains challenging for demographic vegetation models.
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影响因子：
16.6
作者：
Sommerfeld A;Senf C;Buma B;D'Amato AW;Després T;Díaz-Hormazábal I;Fraver S;Frelich LE;Gutiérrez ÁG;Hart SJ;Harvey BJ;He HS;Hlásny T;Holz A;Kitzberger T;Kulakowski D;Lindenmayer D;Mori AS;Müller J;Paritsis J;Perry GLW;Stephens SL;Svoboda M;Turner MG;Veblen TT;Seidl R
通讯作者：
Seidl R
影响因子：
4.8
作者：
BAZZAZ, FA;MIAO, SL
通讯作者：
MIAO, SL
影响因子：
5
作者：
Friedman, SK;Reich, PB
通讯作者：
Reich, PB
冠层辐射参数不确定性对陆地碳和能量循环模型预测的影响
影响因子：
3.7
作者：
T. Viskari;A. Shiklomanov;M. Dietze;S. Serbin
通讯作者：
S. Serbin
DOI：
10.1029/2018jg004504
发表时间：
2018-12
期刊：
Journal of Geophysical Research: Biogeosciences
影响因子：
--
作者：
B. Raczka;M. Dietze;S. Serbin;K. Davis
通讯作者：
B. Raczka;M. Dietze;S. Serbin;K. Davis