Collaborative Research: EAGER: Pathways and patterns of litter chemistry during decomposition

微生物对棚内植物部分（升）的分解称为分解，是所有生态系统中能量流动和养分循环不可或缺的基本生态过程。许多早期的研究已经描述了凋落物的初始化学组成与其分解速度的关系。但对腐烂的后期阶段知之甚少，这对土壤和生态系统的长期稳定很重要。如果最初的化学反应实际上并不像人们通常认为的那样与长期分解有关，那么我们的理解就比想象的要有限得多。该项目利用了多年来从广泛的生态系统中收集的大量存档凋落物样本。研究人员将把现有的凋落物化学数据与这些存档样本的新分析结合起来，探索整个分解过程中凋落物化学的更普遍模式。该项目将把研究和教育与亚利桑那州立大学西校区的本科生结合起来，该校区为一个非常多样化的社区提供服务，其中第一代大学生的比例很高。此外，将为K-12教师开发一个分解模块，用于亚利桑那州的初中和高中科学课。研究人员将利用多个相关机构来协调本科生的教学和参与研究，而新罕布什尔大学的集中培训将使研究生能够在密切合作中学习新技术。最后，除了在同行评议的期刊上发表研究结果外，还建议召开一次特别会议，让更多的科学家参与讨论这一重要主题。该项目将确定不同植物凋落物类型是否在整个腐烂过程中保持其初始化学差异，是否像通常假设的那样保持化学独特性，或者分解凋落物是否遵循不同的化学轨迹，在分解过程中收敛或发散。此外，本研究将确定这些模式与腐烂率的关系，并确定可能影响分解过程中凋落物化学模式和时间变化的当地环境驱动因素，包括气候和分解者群落。这个项目的结果将有助于确定在包括森林、沙漠和农田在内的一系列陆地生态系统的腐烂过程中，已知影响分解的凋落物化学特征是否遵循一致的模式。这将有助于解决初始凋落物化学是否是衰变速率的主要决定因素的问题。该项目还将记录和解释目前使用的许多分析方法所产生的差异，这些差异应在今后的研究中加以考虑。通过利用现有数据和大量存档的垃圾样本，可以大大减少实现这些目标所需的新资源。

The breakdown of shed plant parts (liter) by microbes, called decomposition, is a fundamental ecological process integral to the flow of energy and cycling of nutrients in all ecosystems. Many earlier studies have described how the initial chemical makeup of litter relates to its decomposition rate. But much less is known about the later stages of decay, which are important for long-term stability of soils and ecosystems. If initial chemistry is not in fact related to long-term decomposition, as is usually assumed, then our understanding is much more limited than thought. This project takes advantage of a large set of archived litter samples collected from a wide range of ecosystems over many years. The investigators will combine existing data on litter chemistry with new analyses of these archived samples to explore more general patterns of litter chemistry throughout the entire decomposition process. This project will integrate research and education with undergraduates at the West Campus of Arizona State University that serves a very diverse community with a high percentage of first-generation college students. In addition, a decomposition module will be developed for K-12 teachers to use in Arizona middle and high school science classes. The investigators will take advantage of the multiple institutions involved to coordinate undergraduate student teaching and involvement in research, while centralized training at the University of New Hampshire will enable graduate students to learn new techniques in close collaboration. Finally, in addition to publishing results in peer-reviewed journals, a special session is proposed for a national meeting to engage a larger group of scientists in discussions of this important topic.This project will determine whether diverse plant litter types maintain their initial chemical differences throughout decay, remaining chemically unique as often assumed, or if decomposing litter follows different chemical trajectories to either converge or diverge over the course of decomposition. Further, this study will determine how these patterns relate to decay rate and identify the local environmental drivers, including climate and decomposer communities, that may influence the patterns and temporal variability in litter chemistry during decomposition. The results of this project will help determine whether the suite of litter chemical characteristics known to influence decomposition follow consistent patterns throughout decay across a range of terrestrial ecosystems that includes forests, deserts and agricultural fields. It will help settle the issue of whether or not initial litter chemistry is the main determinant of decay rates. The project will also document and explain differences resulting from the many analytical methods currently used that should be taken into account in future studies. By leveraging existing data and a large set of archived litter samples, the new resources needed to achieve these objectives are greatly reduced.