PDF(Pubmed)
Abstract：
Plant functional traits hold the potential to greatly improve the understanding and prediction of climate impacts on ecosystems and carbon cycle feedback to climate change. Traits are commonly used to place species along a global conservative-acquisitive trade-off, yet how and if functional traits and conservative-acquisitive trade-offs scale up to mediate community and ecosystem fluxes is largely unknown. Here, we combine functional trait datasets and multibiome datasets of forest water and carbon fluxes at the species, community, and ecosystem-levels to quantify the scaling of the tradeoff between maximum flux and sensitivity to vapor pressure deficit. We find a strong conservative-acquisitive trade-off at the species scale, which weakens modestly at the community scale and largely disappears at the ecosystem scale. Functional traits, particularly plant water transport (hydraulic) traits, are strongly associated with the key dimensions of the conservative-acquisitive trade-off at community and ecosystem scales, highlighting that trait composition appears to influence community and ecosystem flux dynamics. Our findings provide a foundation for improving carbon cycle models by revealing i) that plant hydraulic traits are most strongly associated with community- and ecosystem scale flux dynamics and ii) community assembly dynamics likely need to be considered explicitly, as they give rise to ecosystem-level flux dynamics that differ substantially from trade-offs identified at the species-level.
摘要：
植物功能性状具有极大地改善对气候对生态系统的影响以及对气候变化的碳循环反馈的理解和预测的潜力。性状通常用于将物种置于全球保守-获取的权衡之中，然而，功能特征和保守-获取性权衡如何以及是否扩大到调节社区和生态系统通量的程度在很大程度上是未知的。这里,我们将物种森林水和碳通量的功能性状数据集和多生物群落数据集结合起来，社区,和生态系统水平，以量化最大通量和对蒸气压不足的敏感性之间的权衡比例。我们发现在物种规模上有很强的保守-获取权衡，在社区规模上略有减弱，在生态系统规模上基本消失。功能性状，特别是植物水分运输(水力)特征，在社区和生态系统尺度上与保守-获取权衡的关键维度密切相关，强调性状组成似乎会影响群落和生态系统通量动态。我们的发现为改善碳循环模型提供了基础，揭示了i）植物水力性状与社区和生态系统尺度通量动态最密切相关，以及ii）可能需要明确考虑社区组装动态，因为它们产生的生态系统层面的通量动态与物种层面的权衡有很大不同。
