Dissertation research: Does long-term drought alter the response of microbial communities to moisture?

论文研究：长期干旱是否会改变微生物群落对水分的反应？

• 批准号: 1110559
• 负责人: Matthew Wallenstein
• 金额: $ 1.47万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2013-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1110559&HistoricalAwards=false
• 关键词: Dissertation; research; Does; long; term

Molecular advances in recent decades have revealed the immense diversity of microorganisms that inhabit the soil. These microorganisms depend on moisture to regulate the water balance in their cells and access food. Drought is expected to increase in areas of the US West, likely causing more frequent water stress for these organisms. Other organisms, like plants, differ in their sensitivity to drought, and this causes the composition of the community to shift under drought, sometimes to one that responds differently to water. Despite the important role of microorganisms in the cycling of nutrients, and predictions of harsher climates, we know little about how these communities might change under drought or other disturbances. This project will study how these soil microbial communities will change under drought, and whether these new drought-tolerant communities respond differently to moisture than non-drought communities. To answer this question, soils will be collected from a long-term drought manipulation in a Colorado grassland and subject both non-drought and drought soils to a range of moisture levels in the lab. To describe how the community changed, two exciting new technologies will be used. First, microorganisms that are active in the soil will be isolated. Since microorganisms are able to survive in a dormant state for long periods of time, much like seeds, it is important to separate the actively growing microorganisms - those that are affecting the function of the ecosystem - from those that are dormant. Second, high-throughput sequencing and sample taxonomy at a fine resolution will be used to report whole-community changes as well as which species in particular might be more or less sensitive to drought.This research will elucidate how soil microbial communities might shift under drier climates, how this might influence nutrient cycles these communities control, and also how microbial communities, compared to plants and animals, respond to and recover from disturbance. The findings will both refine general ecological principles of how communities respond to disturbance, and improve our ability to predict changes and feedbacks that might occur under different climate regimes.

近几十年来，分子进步揭示了居住在土壤中的微生物的巨大多样性。这些微生物依赖水分来调节其细胞中的水平并进入食物。预计干旱将在美国西部地区增加，这可能会导致这些生物体频繁的水压。其他生物（如植物）对干旱的敏感性有所不同，这会导致社区的组成在干旱下转移，有时转变为对水的反应不同。尽管微生物在养分循环中的重要作用以及对气候变化的预测，但我们对这些社区在干旱或其他干扰下可能会发生变化一无所知。该项目将研究这些土壤微生物群落如何在干旱下变化，以及这些新的耐旱社区对水分的反应是否与非干旱社区不同。为了回答这个问题，将从科罗拉多草原的长期干旱操纵中收集土壤，并将非干旱和干旱土壤降低到实验室的一系列水分水平。为了描述社区的变化，将使用两种令人兴奋的新技术。首先，将分离在土壤中活跃的微生物。由于微生物能够长时间在休眠状态下生存，就像种子一样，重要的是要将主动生长的微生物（那些影响生态系统功能的微生物与处于休眠状态的微生物）分开。其次，将使用精细分辨率的高通量测序和样本分类法来报告全部社区的变化，尤其是哪些物种可能对干旱敏感或多或少敏感。这项研究将阐明土壤微生物群落在干燥的气候下可能会在更干燥的气候下变化，这可能如何影响这些社区的养分，以及这些社区的控制以及对动植物的影响，与动植物相比，与动植物相比，与动植物相比，与之相比，与动植物相比，并康复。这些发现都将完善社区如何应对干扰的一般生态原则，并提高我们预测不同气候制度下可能发生的变化和反馈的能力。