COLLABORATIVE RESEARCH: Will climate change alter rates of old field succession across the U.S. Eastern Deciduous Forest? A cross-latitude experimental network

合作研究：气候变化会改变美国东部落叶林的旧田演替率吗？

• 批准号: 1119715
• 负责人: Justin Wright
• 金额: $ 35.12万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2016-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1119715&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Will; climate; change

Abandoned agricultural land in the Eastern United States returns to forest in a well-established pattern in which "old fields" of herbs and grasses gradually give way to trees. This field-to-forest transition is a key event in ecosystem development because it drives wildlife abundance, influences how ecosystems store carbon and cycle nutrients, and often changes the balance between landscapes dominated by alien or native plant species. One puzzling aspect of this process is that old fields can persist for decades in the Northeast, but tend to transition to forests in less than 10 years in the Southeast, despite having many of the "field invading" tree species in common. Is this due to the warmer climate of the Southeast, where trees can grow more quickly in competition with herbs and grasses? If so, will "old fields" become forests more quickly as the climate warms? Alternatively, the regions may be different in other ways (e.g. soil quality). In this project the PIs have designed an experiment to definitively answer this question, using a network of six field experiments from New York to Florida. At each site, researchers will control the composition of the old field plants and invading trees (using species common to both the North- and Southeast), as well as varying the soil conditions to approximate northern and southern soils. Researchers will monitor the rate at which trees invade each experimental community, and use the results to formulate a model that can make predictions about how climate, soil fertility, and characteristics of particular species influence the rate of forest development in the Eastern United States.These results will be key for understanding how agricultural landscapes of the Eastern United States will continue to change over the next century, and will inform stakeholders on land management issues with respect to carbon sequestration, biological diversity, and other ecosystem services. Two graduate students and several undergraduates will be trained, through the support of two junior faculty. The project also includes use of several core ecological research facilities in the Eastern United States.

美国东部被遗弃的农田以一种既定的模式回归森林，在这种模式中，草药和草的“老田”逐渐让位于树木。 这种从农田到森林的过渡是生态系统发展中的一个关键事件，因为它推动了野生动物的丰富，影响了生态系统储存碳和循环养分的方式，并经常改变外来或本土植物物种主导的景观之间的平衡。 这一过程的一个令人困惑的方面是，东北部的老田地可以持续几十年，但在东南部，尽管有许多共同的“田地入侵”树种，但往往在不到10年的时间内过渡到森林。 这是因为东南部气候温暖，树木可以在与草药和草的竞争中生长得更快吗？ 如果是这样，随着气候变暖，“老田”会更快变成森林吗？ 或者，这些区域在其他方面可能不同（例如土壤质量）。在这个项目中，PI设计了一个实验来明确回答这个问题，使用从纽约到佛罗里达的六个现场实验网络。 在每个地点，研究人员将控制旧的田间植物和入侵树木的组成（使用北部和东南部共同的物种），以及改变土壤条件，以接近北方和南部的土壤。 研究人员将监测树木入侵每个实验社区的速度，并利用结果制定一个模型，该模型可以预测气候，土壤肥力和特定物种的特征如何影响美国东部的森林发展速度。这些结果将是了解美国东部农业景观在下一个世纪将如何继续变化的关键，并将向利益攸关方通报与固碳、生物多样性和其他生态系统服务有关的土地管理问题。 两名研究生和几名本科生将通过两名初级教师的支持进行培训。 该项目还包括使用美国东部的几个核心生态研究设施。