DISSERTATION RESEARCH: Secondary Production in Urban Stream Food Webs: From Pattern to Process

论文研究：城市溪流食物网的二次生产：从模式到过程

• 批准号: 0808035
• 负责人: Margaret Carreiro
• 金额: $ 1.2万
• 依托单位: University of Louisville Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0808035&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Secondary; Production; Urban

Urban land use and future urban expansion pose a serious threat to natural ecosystems. Urban areas rely on outside support from natural ecosystems for resource acquisition and waste disposal. As a consequence, streams in urban systems are affected by multiple disturbances within the watershed, and, in many cases, serve as waste conduits for municipal wastewater discharge. In addition, changes in watershed hydrology due to increased impervious surfaces (i.e. roads, buildings, parking lots) drastically affect stream channel geomorphology by deepening and widening the stream to accommodate new flow patterns. These physical and chemical changes in stream conditions generally result in decreased biological diversity of stream dwelling organisms. An unaddressed question, however, is how reductions in community richness and diversity affect the ecosystem functions and services provided by urban stream communities. In this study, this question will be addressed by conducting experiments in six streams draining watersheds in which land use varies from 0 to 80% urban cover to determine not only how biological diversity within the stream is impacted by urbanization, but what consequences these losses in biological diversity have in terms of energy flow and nutrient cycling within stream food webs, two processes with profound consequences for in-stream water quality. Dissemination of these results will facilitate the future planning, management, and restoration of urbanized streams by linking commonly observed decreases in stream biological diversity with measureable ecosystem scale functions and services provided by the stream organisms.

城市土地利用和未来城市扩张对自然生态系统构成严重威胁。城市地区依靠自然生态系统的外部支持来获取资源和处理废物。因此，城市系统中的溪流受到流域内多重扰动的影响，并且在许多情况下，充当城市废水排放的废物管道。此外，由于不透水表面（即道路、建筑物、停车场）增加而导致流域水文发生变化，加深和加宽河流以适应新的流动模式，从而极大地影响河道地貌。河流条件的这些物理和化学变化通常会导致河流栖息生物的生物多样性降低。 然而，一个尚未解决的问题是社区丰富度和多样性的减少如何影响城市河流社区提供的生态系统功能和服务。 在本研究中，将通过在六个流域的排水流域中进行实验来解决这个问题，其中土地利用的城市覆盖率从 0% 到 80% 不等，不仅确定河流内的生物多样性如何受到城市化的影响，还确定这些损失对城市化造成的影响。生物多样性涉及溪流食物网内的能量流动和养分循环，这两个过程对溪流水质产生深远影响。 这些结果的传播将通过将普遍观察到的河流生物多样性的减少与河流生物提供的可测量的生态系统规模功能和服务联系起来，促进城市化河流的未来规划、管理和恢复。