The Application Of Scaling Rules To Energy Flow In Stream Ecosystems

尺度规则在溪流生态系统能量流中的应用

• 批准号: 0109122
• 负责人: Louis Kaplan
• 金额: $ 15万
• 依托单位: Stroud Water Research Center
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-15 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0109122&HistoricalAwards=false
• 关键词: Application; Scaling; Rules; Energy; Flow

Abstract Kaplan 0109122 The investigators propose to estimate the contribution of dissolved organic matter (DOM) in transport to the support of stream ecosystem metabolism. The specific objective of this project is to estimate the mass flux of DOM (e.g., the rate of flux from the water column to the streambed), to represent this as the sum of fluxes from several lability classes, and to characterize the respective concentration and uptake length coefficient of DOM in each lability class. Uptake length converts easily to mass transfer coefficient or turnover rate through scaling relationships involving depth and water velocity. Quantifying the uptake of natural DOM in the stream is analogous to describing the uptake (or spiraling) of phosphorus or ammonium, but is complicated by the diversity of natural DOM (i.e. it consists of an array of compounds of varying lability), and the fact that isotopically-labeled natural DOM is not available. This project will use 13C-labeled DOM generated by growing plants in a 13C atmosphere. The longitudinal uptake of 13C -DOm will be resolved into multiple uptake lengths (corresponding to multiple lability classes), estimated as the sum of exponential-curves. In addition, the uptake kinetics of natural (12C) DOM in laboratory bioreactors will be compared to those of the labeled 13C-DOM, and this comparison will be used to scale the results of the 13C-DOM injection, to appropriately describe the uptake of natural DOM in the stream.

摘要/ Abstract摘要：研究人员提出估算河流中溶解有机物（DOM）在运输过程中对河流生态系统代谢的支持作用。该项目的具体目标是估计DOM的质量通量（例如，从水柱到河床的通量率），将其表示为几个不稳定类别的通量之和，并表征每个不稳定类别中DOM的各自浓度和吸收长度系数。通过涉及深度和水速度的缩放关系，吸收长度很容易转换为传质系数或周转率。量化河流中天然DOM的吸收类似于描述磷或铵的吸收（或螺旋），但由于天然DOM的多样性（即它由一系列不同稳定性的化合物组成）和同位素标记的天然DOM不可用的事实而变得复杂。该项目将使用13C标记的DOM，该DOM是在13C的大气中种植植物产生的。13C -DOm的纵向吸收将被分解成多个吸收长度（对应于多个不稳定等级），估计为指数曲线的和。此外，将实验室生物反应器中天然（12C） DOM的摄取动力学与标记的13C-DOM的摄取动力学进行比较，并将这种比较用于缩放13C-DOM注射的结果，以适当地描述溪流中天然DOM的摄取。