Dissertation Research: Production of Microbial ExtracellularPolysaccharides and Their Assimilation by Stream Invertebrates

论文研究：微生物胞外多糖的产生及其溪流无脊椎动物的同化

• 批准号: 8815237
• 负责人: Judith Meyer
• 金额: $ 0.71万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-12-01 至 1990-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8815237&HistoricalAwards=false
• 关键词: Dissertation; Research; Production; Microbial; ExtracellularPolysaccharides

Microbial extracellular polysaccharides are ubiquitous in the epilithon covering submerged lotic surfaces, yet their significance to carbon transfer in these ecosystems is unknown. The proposed research will estimate production of bacterial and algal biomass and the production of microbial extracellular polysaccharide on wood substrates in the Ogeechee River, a sixth order blackwater river, and measure the efficiency with which extracellular polysccharide may be assimilated by nymphal ayflies and by oligochaets. Assimilation of extracellular polysaccharide will be determined by feeding studies using 14C labelled extracellular polysaccharides. These polysaccharides will be purified form cultures of slime-producing bacteria which have been isolated from wood submerged in the Ogeechee River. Oak dowels in stream-side flumes will be used as subtrates for microbial colonization. If extracellular polysaccharides are assimilated by freshwater invertebrates, the contribution of microbes to invertebrate productivity would be much greater than suggested by estimates of cellular consumption alone. The assimilation of these products of microbial metabolism may contribute to meeting detritivore carbon requirements in many aquatic habitats where cellular microbial biomass is insufficient to meet detritivore needs. This research should be of significant basic ecological interest and produce results with meaning for stream management. The student's mentor is an excellent scientist, and institutional accommodations are good. The Ecosystem Studies Program recommends support for this doctoral dissertation improvement project.

微生物胞外多糖普遍存在于覆盖在水面上的浮游生物中，但它们在这些生态系统中对碳转移的意义尚不清楚。拟议的研究将估计六级黑水河Ogeechee河木质基质上细菌和藻类生物量的产量以及微生物胞外多糖的产量，并测量胞外多糖被若虫和寡毛虫同化的效率。胞外多糖的同化将通过14C标记的胞外多糖的喂养研究来确定。这些多糖将从从淹没在Ogeechee河中的木材中分离出来的粘液产生细菌的培养中提纯。溪边水槽中的橡木桩将用作微生物定植的底物。如果细胞外多糖被淡水无脊椎动物同化，微生物对无脊椎动物生产力的贡献将远远超过仅对细胞消耗的估计。这些微生物代谢产物的同化可能有助于满足许多水生生境的有害碳需求，在这些生境中，细胞微生物生物量不足以满足有害的碳需求。本研究具有重要的基础性生态意义，并取得了对河流管理有意义的成果。这名学生的导师是一位优秀的科学家，机构的安排也很好。生态系统研究计划建议支持这一博士论文改进项目。