LTREB Renewal: Drivers of temperate forest carbon storage from canopy closure through successional time

森林干扰，如皆伐和火灾，通常会导致森林及其土壤中的碳和养分大量流失。事实上，美国东部的所有森林都在从这种干扰中恢复过来，无论是自然的还是人为的。然而，人们还不清楚是什么机制控制森林碳和养分储量的恢复时间后，干扰。 同样不为人知的是，植物生长、土壤发育和气候变化如何相互作用地调节老化森林中碳和养分的回收。该项目使用密歇根大学生物站（密歇根州北方一个有110年历史的野外站）的长期实验地块，调查森林的变化如何导致整体碳捕获和储存。在全球范围内，森林消除了化石燃料燃烧产生的约1/4的碳排放，而温带森林，如本文所研究的森林，几乎占大气中碳排放量的一半。然而，在过去的大规模干扰之后，随着森林的老化和成熟，森林是否会继续部分抵消人类产生的碳排放，这是不确定的。该项目提供了关键数据和机制的理解，需要预测的规模和持续时间的温带森林碳吸收，以及森林的能力，提供纤维，燃料，栖息地，和许多其他利益的社会。这个长期（10年）的项目开始回答全球重大问题，在其富有成效的第一个5年。研究人员正在测量6个森林的森林和土壤（约100公顷）。2英亩），在1936年，1948年，1954年，1980年，1998年或2017年进行了实验性切割和燃烧。这些砍伐和焚烧处理复制了20世纪初发生在五大湖地区的大规模砍伐和焚烧，实验林就坐落在该地区。森林结构测量包括树、叶和分支密度和排列的格局。土壤测量包括养分分布和可用性以及土壤碳通量。利用附近的古老森林（130- 200岁），没有严重削减和烧毁作为参考点，该小组正在联系干扰，气候，土壤和植被控制的长期模式的碳封存在森林是代表其他森林在北方美国和加拿大类似地区，欧洲和亚洲。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Forest disturbances, such as clear-cutting and fire, typically lead to large losses of carbon and nutrients from forests and their soils. Virtually all forests in the Eastern US are recovering from such disturbances, whether natural or human-caused. It is, however, not well understood what mechanisms control recovery times of forest carbon and nutrient stocks following disturbance. Also not well known is how plant growth, soil development and climate variation interactively regulate recoveries of carbon and nutrients in aging forests. This project uses long-term experimental plots at the University of Michigan Biological Station (a 110-year-old field station in northern Michigan) to investigate how changes in forests lead to overall carbon capture and storage. Globally, forests remove approximately 1/4 of carbon emissions from fossil fuel combustion, with temperate forests, like those studied here, being responsible for almost half of that carbon removal from the atmosphere. However, it is uncertain whether forests will continue to partially offset human-derived carbon emissions as they age and mature following past large-scale disturbances. This project provides critical data and mechanistic understanding needed to predict the magnitude and duration of continued temperate forest carbon uptake, and the ability of forests to provide fiber, fuel, habitat, and many other benefits to society.This long-term (10-year) project began to answer globally significant questions in its productive first 5 years. Researchers are measuring the forests and soils in 6 forest stands (approx. 2 acres each) that were experimentally cut and burned in either 1936, 1948, 1954, 1980, 1998, or 2017. These cutting and burning treatments replicate larger-scale cutting and burning that occurred in the early 1900s across the Great Lakes region within which the experimental stands are nested. Forest structural measurements include patterns of tree, leaf, and branch density and arrangement. Soil measurements include both nutrient distribution and availability and soil carbon fluxes. By using nearby old forests (130- to 200-yr-old) that were not severely cut and burned as reference points, the team is linking disturbance, climate, soil, and vegetation controls to long-term patterns of carbon sequestration in forests that are representative of other forests across the northern U.S. and similar regions in Canada, Europe and Asia.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.