The Influence of Tree Species on Soil Organic Matter Dynamics in Temperate Forests

森林土壤含有比整个大气都多的碳，因此森林土壤和大气之间的二氧化碳交换会影响全球碳循环和气候变化。今天森林中正在发生的变化，包括优势树种身份的转变和外来蚯蚓物种的入侵，都有可能扰乱这些生态系统的碳平衡。不幸的是，这两种干扰对森林土壤碳储量的影响在很大程度上是未知的。这项提议的目的是在波兰进行一项独特的田间试验，研究树种和蚯蚓对土壤碳储量的影响。35年前，波兰种植了14种不同的树种。在这个地点，众所周知，树种在它们所支持的蚯蚓种群和其他可能影响土壤碳的质量方面存在差异，包括树叶和细根特征。这项建议中提出的研究将把这些已知的物种差异与使用先进的分子和同位素分析工具对土壤碳动态进行新的研究联系起来。通过明确树种、蚯蚓和土壤碳储量之间的关系，可以更好地了解树种组成变化和蚯蚓入侵对森林碳平衡的影响。这些信息可用于管理美国森林的物种组成，以固碳为目的，促进参与旨在碳管理和气候变化缓解的经济和政治追求。

Forest soils contain more carbon than the entire atmosphere and thus the exchange of carbon dioxide between forest soils and the atmosphere can influence the global carbon cycle and climate change. Changes taking place in forests today, including shifts in the identity of dominant tree species and exotic earthworm species invasions, threaten to perturb the carbon balance of these ecosystems. Unfortunately, the effect of these two disturbances on forest soil carbon storage is largely unknown. The intent of this proposal is to study the influence of tree species and earthworms on soil carbon storage at a unique field experiment in Poland, where 14 different tree species were planted more than 35 years ago. At this site, tree species are known to differ with respect to the earthworm populations they support and other qualities that could influence soil carbon, including leaf and fine root characteristics. The research put forth in this proposal will relate these known species differences to new studies of soil carbon dynamics using advanced molecular and isotopic analytical tools. By defining clear relationships between tree species, earthworms, and soil carbon storage, the consequences of changing tree species composition and earthworm invasions on the carbon balance of forests can be better understood. This information could be used to manage the species composition of U.S. forests for the purpose of carbon sequestration, facilitating participation in economic and political pursuits aimed at carbon management and climate change mitigation.