A climate-driven switch in plant nitrogen acquisition within tropical forest communities
A climate-driven switch in plant nitrogen acquisition within tropical forest communities
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DOI：
10.1073/pnas.0609935104
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发表时间：
2007-05-22
影响因子：
11.1
通讯作者：
Hedin, Lars O.
中科院分区：
文献类型：
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作者：
Houlton, Benjamin Z.;Sigman, Daniel M.;Hedin, Lars O.
热带森林对气候变化的反应将取决于个别植物物种的营养策略，而对于维持植物生长和光合作用至关重要的氮素营养来说，营养策略尚未确定。我们使用同位素的自然丰度表明，一组热带植物物种与不同的增长策略（树木和蕨类植物，树冠，和subcanopy）依赖于一个共同的池的无机氮，而不是专门在不同的氮池。此外，我们研究的热带物种突然改变了他们的主导氮源，并一致，响应降水量的变化。这种阈值响应表明，物种之间的一致性策略，以利用土壤中最有效的氮的形式。明显的社区范围内的氮吸收的灵活性表明，热带森林中的不同物种可以生理跟踪气候变化引起的氮循环的变化。
The response of tropical forests to climate change will depend on individual plant species' nutritional strategies, which have not been defined in the case of the nitrogen nutrition that is critical to sustaining plant growth and photosynthesis. We used isotope natural abundances to show that a group of tropical plant species with diverse growth strategies (trees and ferns, canopy, and subcanopy) relied on a common pool of inorganic nitrogen, rather than specializing on different nitrogen pools. Moreover, the tropical species we examined changed their dominant nitrogen source abruptly, and in unison, in response to precipitation change. This threshold response indicates a coherent strategy among species to exploit the most available form of nitrogen in soils. The apparent community-wide flexibility in nitrogen uptake suggests that diverse species within tropical forests can physiologically track changes in nitrogen cycling caused by climate change.