Desert Microbial Activity in the Rhizosphere Oasis

根际绿洲的沙漠微生物活动

• 批准号: 0415938
• 负责人: Zoe Cardon
• 金额: --
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0415938&HistoricalAwards=false
• 关键词: Desert; Microbial; Activity; Rhizosphere; Oasis

In desert ecosystems, plant growth and reproduction are limited by water availability, but also by nitrogen and other soil nutrients. Soil fungi and bacteria are responsible for recycling nutrients from dead material into forms that plants can use, but low water availability can limit the ability of soil microbes to carry out such transformations. Interestingly, the roots of some deep-rooted desert plants can act as conduits for passive water movement from moist soil layers into shallow, drier layers where detritus is abundant, in a process called hydraulic redistribution. Microbial activity may be stimulated around roots by this movement of water into dry soil. This research project will include integrated greenhouse and field studies that take advantage of the ability of Artemisia tridentata (common sagebrush) to redistribute water from wetter to drier soil layers in Western U.S. landscapes. Using microbiosensors in greenhouse experiments, and soil, plant, and microbial assays in Utah field sites, hydraulic redistribution of water by sagebrush roots will be examined for its ability to promote soil nutrient cycling and nutrient availability. Enhanced nutrient availability may in turn lead to enhanced photosynthesis, growth, and reproductive yield of plants actively redistributing water. As a companion to the research, an exhibit will be developed at the Worcester Ecotarium that provides several primary messages, including: 1. Soil is alive with beneficial microbes, and 2. Roots are two-way streets which can both take up and release water.

在沙漠生态系统中，植物的生长和繁殖不仅受到水资源的限制，还受到氮和其他土壤养分的限制。 土壤真菌和细菌负责将死亡物质中的营养物质再循环成植物可以使用的形式，但低水可用性会限制土壤微生物进行这种转化的能力。 有趣的是，一些根深蒂固的沙漠植物的根可以作为被动水运动的管道，从潮湿的土壤层到浅层，干燥的层，在那里有大量的碎石，在一个过程中称为水力再分配。通过这种水分进入干燥土壤的运动，可以刺激根部周围的微生物活动。 该研究项目将包括综合温室和实地研究，利用蒿（普通蒿属植物）的能力，将水从美国西部的湿润土壤层重新分配到干燥土壤层。 在温室实验中使用微生物传感器，并在犹他州实地进行土壤，植物和微生物测定，将检查水的水力再分配的山艾属植物的根，以促进土壤养分循环和养分的可用性。 养分有效性的提高反过来又会导致植物主动重新分配水分的光合作用、生长和生殖产量的提高。 作为研究的伴侣，将在伍斯特生态馆举办一个展览，提供几个主要信息，包括：1。土壤是活的有益微生物，和2。根是双向的街道，既可以吸收和释放水。