Pulsing of Plant-available Moisture & Nitrogen in Great Basin Communities: Interactions of Microbial Processes, Root Depth Distributions and Hydraulic Lift

摘要 提案编号：DEB-9807097 经销商：考德威尔 研究机构：犹他州州立大学 该提案的目的是调查不同生命形式的植物和土壤微生物如何对大盆地生态系统中的土壤水分和氮脉冲做出反应并影响土壤水分和氮脉冲。 位于犹他州州立大学的5名主要研究人员具有从微生物学到遥感的专业知识，他们从不同的角度和规模开发了一个集中于这些问题的综合研究设计。 液压升降机的作用（即，在深层吸水和夜间释放到上层土壤层）的特点，作为一个过程，可能是特别重要的，在促进获取水和氮在面对时间的变化。 其他重点包括研究根分布的意义，在微生物的过程中，介导的氮在可变环境中的可用性，并在不同的植物生命形式的作用。 虽然这项研究是在大盆地生物群落，这些主题是有关几乎所有的陆地生态系统，包括农业系统，也有明确的影响陆地生态系统对全球环境变化的反应。 这项工作也有相当大的impor 6 t流域水文和人类操纵的植被在大盆地。

ABSTRACT PROPOSAL # : DEB-9807097 INVESTIGATOR(S) : CALDWELL INSTITUTION: UTAH STATE UNIVERSITY The aims of this proposal are to investigate how plants of different life forms and soil microbes react to and influence soil moisture and nitrogen pulses in a Great Basin ecosystem. Based at Utah State University, 5 principal investigators with expertise ranging from microbiology to remote sensing have developed an integrated research design focused on these issues from different perspectives and scales. The role of hydraulic lift (i.e., water absorption at depth and nocturnal release into upper soil layers) is featured, as a process that may be particularly important in facilitating acquisition of both water and N in the face of temporal variability. Other emphases include research on the significance of root distributions, on microbial processes that mediate N availability in variable environments, and on the role of different plant life forms. Although the study is set in the Great Basin biome, these topics are relevant to almost all terrestrial ecosystems including agricultural systems, and there are also clear implications for response of terrestrial ecosystems to global environmental change. The work also has considerable impor6t for watershed hydrology and human manipulation of vegetation in the Great Basin.