Integrating regional climate change into allometric equations for estimating tree aboveground biomass of Masson pine in China
Integrating regional climate change into allometric equations for estimating tree aboveground biomass of Masson pine in China
复制标题
将区域气候变化纳入异速生长方程估算中国马尾松树体地上生物量
DOI：
10.1007/s13595-017-0636-z
复制
发表时间：
2017-06-01
影响因子：
3
通讯作者：
Liang, Jingjing
中科院分区：
文献类型：
--
作者：
Fu, Liyong;Lei, Xiangdong;Liang, Jingjing
本文建立了一个气候敏感的地上生物量（AGB）方程，并结合非线性混合效应模型和虚拟变量方法，研究了气候变化对树木直径和生物量之间异速生长关系的影响。研究结果表明，在估算马尾松的AGB时，应考虑这种异速生长的变化。森林在维持森林生态系统功能和减缓大气中碳浓度增加方面发挥着关键作用。传统的生物量异速生长方程不考虑气候对直径生物量关系的潜在影响。这种影响的幅度仍然记录不佳.Aims我们提出了一种新的方法来检测长期（2041-2080年）气候变化对直径生物量的关系和潜在的后果的长期变化的生物量积累的马尾松.Methods我们的方法是基于一个气候敏感的AGB模型开发的组合非线性mixedeffects模型和虚拟变量的方法。评估了各种气候相关变量对模型改进的贡献。结果表明，胸径、生长季长期平均气温、生长季总降水量、最湿季平均气温和最湿季降水量对AGB值有显著影响。生长季降水偏多和最湿润区平均气温偏高降低了AGB，而温暖的生长季和最湿润区降水偏多则增加了AGB。与传统的无气候影响的生物量模型相比，本研究开发的新的气候敏感的异速生长模型可以改善生物量的预测。研究结果表明，在未来2041- 2080年，相同胸径的马尾松在代表性浓度路径（RCP）2.6、RCP 4.5和RCP 8.5三种气候情景下的AGB将增加24.8 ± 32.7%（平均值+/-标准差）、27.0 +/-33.4%和27.7 +/- 33.8%。因此，我们可以预期，在气候变化下，生物量估计会有很大的区域差异和不确定性。
Key message A climate-sensitive aboveground biomass (AGB) equation, in combination with nonlinear mixedeffectsmodeling and dummy variable approach, was developed to examine how climate changemay affect the allometric relationships between tree diameter and biomass. We showed that such changes in allometry need to be taken into account for estimating tree AGB in Masson pine.Context As a native species and being widely distributed in subtropical China, Masson pine (Pinus massoniana Lamb.) forests play a pivotal role in maintaining forest ecosystem functions and mitigation of carbon concentration increase at the atmosphere. Traditional biomass allometric equations do not account for a potential effect of climate on the diameterbiomass relationships. The amplitude of such an effect remains poorly documented.Aims We presented a novel method for detecting the longterm (2041-2080) effects of climate change on the diameterbiomass relationships and the potential consequences for long-term changes of biomass accumulation for Masson pine.Methods Our approach was based on a climate-sensitive AGB model developed using a combined nonlinear mixedeffects model and dummy variable approach. Various climaterelated variables were evaluated for their contributions to model improvement. Heteroscedasticity was accounted for by three residual variance functions: exponential function, power function, and constant plus function.Results The results showed that diameter at breast height, together with the long-term average of growing season temperature, total growing season precipitation, mean temperature of wettest quarter, and precipitation of wettest quarter, had significant effects on values of AGB. Excessive rain during the growing season and high mean temperature in the wettest quarter reduced the AGB, while a warm growing season and abundant precipitation in the wettest quarter increased the AGB.Conclusion Climate change significantly affected the allometric scale of biomass equation. The new climate-sensitive allometric model developed in this study may improve biomass predictions compared with the traditional model without climate effects. Our findings suggested that the AGB of Masson pine trees with the same diameter at breast height under three climate scenarios including representative concentration pathway (RCP) 2.6, RCP 4.5, and RCP 8.5 in the future period 2041- 2080 would increase by 24.8 +/- 32.7% (mean +/- standard deviation), 27.0 +/- 33.4%, and 27.7 +/- 33.8% compared with the constant climate (19502000), respectively. As a consequence, we may expect a significant regional variability and uncertainty in biomass estimates under climate change.