Camargo Julio A, Alonso Alvaro, de la Puente Marcos
Departamento de Ecología, Facultad de Biología, Universidad de Alcalá, Alcalá de Henares 28871, Madrid, Spain.
Environ Monit Assess. 2004 Aug-Sep;96(1-3):233-49. doi: 10.1023/b:emas.0000031730.78630.75.
In this investigation we evaluated the performance of multiple metrics, based on benthic macroinvertebrates, to assess nutrient enrichment in impounded rivers. Field studies were conducted in the upper reaches of four impounded mountain rivers (Tormes, Riaza, Eresma and Miraflores Rivers) of Central Spain. The watersheds of these rivers are underlain by siliceous rocks. Two sampling sites, upstream and downstream from the reservoir, were established in stony riffles of each impounded river. We used a total of 34 metrics, representing five different metric groups: measures of abundance and richness, percentages of taxonomic groups, percentages of functional feeding groups, measures of dominance and diversity, and biotic indices. Evaluation of different metrics was mainly based on correlation analyses between concentrations of nutrients (NO3-N, NH4-N, PO4-P) and values of individual metrics. Deep releases from the reservoirs were the primary cause responsible for the nutrient enrichment at downstream sampling sites. Chironomidae density, Gastropoda density, % Chironomidae, % Gastropoda, % collector-gatherers and scrapers, proportion of the two most dominant taxa, and Camargo's dominance index exhibited the highest positive correlation coefficients. Conversely, Plecoptera density, Trichoptera density, EPT richness, % Plecoptera, % Trichoptera, % collector-filterers, % predators, % shredders, Simpson's and Camargo's diversity indices, and the average BMWQ score (biotic index) exhibited the highest negative correlation coefficients. Overall it is concluded that the multimetric approach may be a useful technique for the biological assessment of nutrient enrichment in fluvial ecosystems, particularly in upper reaches of siliceous rivers.
在本研究中，我们评估了基于底栖大型无脊椎动物的多个指标在评估蓄水河流营养物富集方面的性能。实地研究在西班牙中部四条蓄水山区河流（托尔梅斯河、里亚萨河、埃雷斯马河和米拉弗洛雷斯河）的上游进行。这些河流的流域由硅质岩构成。在每条蓄水河流的石质浅滩中设置了两个采样点，分别位于水库上游和下游。我们总共使用了34个指标，代表五个不同的指标组：丰度和丰富度测量指标、分类学类群百分比、功能摄食类群百分比、优势度和多样性测量指标以及生物指数。不同指标的评估主要基于营养物浓度（NO3-N、NH4-N、PO4-P）与各个指标值之间的相关性分析。水库的深层放水是下游采样点营养物富集的主要原因。摇蚊科密度、腹足纲密度、摇蚊科百分比、腹足纲百分比、收集者-采集者和刮食者百分比、两个最优势类群的比例以及卡马戈优势度指数呈现出最高的正相关系数。相反，襀翅目密度、毛翅目密度、EPT丰富度、襀翅目百分比、毛翅目百分比、收集者-滤食者百分比、捕食者百分比、碎食者百分比、辛普森和卡马戈多样性指数以及平均BMWQ评分（生物指数）呈现出最高的负相关系数。总体而言，得出的结论是，多指标方法可能是一种用于河流生态系统营养物富集生物评估的有用技术，特别是在硅质河流的上游。
