Residence times of woody biomass in tropical forests
Residence times of woody biomass in tropical forests
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DOI：
10.1080/17550874.2013.770578
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发表时间：
2013-03-01
影响因子：
1.5
通讯作者：
Lloyd, Jon
中科院分区：
文献类型：
--
作者：
Galbraith, David;Malhi, Yadvinder;Lloyd, Jon
背景：生态系统的木质生物量停留时间 ((w)) 是准确模拟其生物量储量的重要变量。方法和结果：我们回顾了热带地区 177 个森林地块的已发表数据，发现整个数据集中的 (w) 存在六倍的变化（23129 年），中位数 (w) 约为 100%。 50 年。该值与 21 个热带森林植被模型的默认中值相似，尽管模型中使用的值范围很大（20 至 200 年）。结论：考虑到 (w) 观测到的较大变化，所有热带森林的常数 (w) 概念的实用性可能有限。我们发现，虽然气候变量和（w）之间关系不大，但有证据表明土壤因素对（w）有很大影响。在新热带区和古热带区，(w) 在严重风化的土壤中最高，表明低土壤肥力和/或非限制性土壤物理条件对 (w) 产生关键影响。全球环境变化，尤其是大气中二氧化碳含量增加，对 (w) 的影响存在相当大的不确定性。即使 (w) 的微小变化也可能显着减少许多植被模型预测的未来热带森林碳汇。
Background: The woody biomass residence time ((w)) of an ecosystem is an important variable for accurately simulating its biomass stocks.Methods and results: We reviewed published data from 177 forest plots across the tropics and found a six-fold variation (23129 years) in (w) across our dataset, with a median (w) of ca. 50 years. This value is similar to the median default value across 21 vegetation models for tropical forests, although the range of values used in models is large (20 to 200 years).Conclusions: The notion of a constant (w) across all tropical forests may be of limited utility, given the large observed variation in (w). We found that while there was little relationship between climate variables and (w), there was evidence that edaphic factors exerted a strong influence on (w). In both the Neotropics and the Paleotropics, (w) was highest in heavily weathered soils, suggesting that low soil fertility and/or non-limiting soil physical conditions exert a critical influence on (w). There is considerable uncertainty in how (w) will be affected by global environmental change, especially by increased atmospheric CO2. Even small changes in (w) could significantly reduce the future tropical forest carbon sink predicted by many vegetation models.