DISSERTATION RESEARCH: Interactive Effects of Fern and Microbial Stoichiometry on Decomposition

论文研究：蕨类植物和微生物化学计量对分解的相互作用

基本信息

批准号：
0508954
负责人：
Peter Vitousek
金额：
$ 1.06万
依托单位：
Stanford University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2005
资助国家：
美国
起止时间：
2005-06-01 至 2007-11-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0508954&HistoricalAwards=false
关键词：
DISSERTATION RESEARCH Interactive Effects Fern

项目摘要

Plants and the microorganisms that decompose them innately contain different amounts of elements such as carbon, nitrogen and calcium. The time it takes for the microbial community to break down plant material is often correlated with plant nutrient concentrations; plants with nutrient concentrations closer to that of fungi and bacteria decompose faster. Because decomposition ultimately controls nutrient availability to plants, understanding why different types of plants decompose differently is important. Distinct plant groups can have different nutrient concentrations that may contribute to differences in decomposition rates. Ferns are a significant component of many terrestrial forests, and often decompose more slowly than angiosperms. Ferns also appear to be nutrient-poor in comparison to angiosperms, and those ferns species that evolved longer ago are nutrient-poor in comparison to evolutionarily younger fern species.In order to test the importance of nutrient content for fern decomposition, we will explore decomposition dynamics of ferns and angiosperms in the laboratory, where we will manipulate the nutrient content of both leaves and soil. Measurements of microbial community composition and leaf elemental content over time will clarify the interactions between nutrient content, fungal/bacterial ratios, and nutrient release and decomposition rates. Stable isotopes of elements such as nitrogen and calcium can be used to trace the movement of nutrients; we will add stable isotopes to the soil in a subset of the experiment, thereby tracking microbial movement of nutrients into decomposing leaves. Additionally, we plant to directly analyze microbial nutrient content using an x-ray attached to a scanning electron microscope. These techniques will further illuminate the fates of nutrients and the influence of plant and soil nutrient content on microbial nutrients.

植物和分解它们的微生物天生包含不同量的元素，例如碳，氮和钙。微生物群落分解植物材料所需的时间通常与植物营养浓度相关。养分浓度更接近真菌和细菌分解的植物更快。由于分解最终会控制植物的养分利用率，因此了解为什么不同类型的植物分解不同是重要的。不同的植物群可以具有不同的营养浓度，这可能导致分解率的差异。蕨类植物是许多陆地森林的重要组成部分，并且通常比被子植物更慢。与被子植物相比，蕨类植物似乎也是营养贫困的贫困，而与进化的年轻蕨类物种相比，那些以前进化的蕨类物种是营养贫困的。为了测试营养含量对于蕨类植物分解的重要性，我们将在ferns and nutrip and nutrip and nutrip conterrip conterrip and nutrip conterrip conterrip conterrip conterrip and nutrip conterrip conterrip and nutr and nutrip conterrip conterrip conterrip conterrip and nutrip conterrip。随着时间的推移，微生物群落组成和叶片元素含量的测量将阐明营养含量，真菌/细菌比例以及养分释放和分解速率之间的相互作用。氮和钙等元素的稳定同位素可用于追踪养分的运动。我们将在实验的一部分中向土壤中添加稳定的同位素，从而跟踪养分的微生物运动为分解叶片。此外，我们使用附着在扫描电子显微镜上的X射线直接分析微生物养分含量。这些技术将进一步阐明养分的命运以及植物和土壤养分含量对微生物养分的影响。