The objectives of this research were to record the changes in composition of the community of ephemeroptera in Plalar-Gremeng river, examine the causes of these changes and discover their significance in the life of t...The objectives of this research were to record the changes in composition of the community of ephemeroptera in Plalar-Gremeng river, examine the causes of these changes and discover their significance in the life of the rivers. The ephemeropteran community and abundance of the feeding group （detritivore, gatherer and scrapper） were compared with the nutrient and water quality of each sampling site. It is established that, under site conditions, nutrient status can be regarded as the chief internal factors. The method was field survey for sampling the substrate at five sites： （I） Up-stream of Plalar river; （2） The site before the Plalar cave; （3） The total dark zone of Plalar-Gremeng caves; （4） The site after Gremeng cave and （5） The down-stream of Gremeng to Beton river. Substrate sampling used Surber benthic sampler and the sample was containing and labeling. Environmental parameters were measured water temperature, carbon dioxide, velocity, pH, C-organic, sediment total-phosphorus and nitrogen and Ca content. The data was analyzed by description. The results showed that the abundance of ephemeroptera was highest at site-4 and the lowest at site-3. Ephemeropthera play a highly important role in preserving nutrient status.展开更多
文摘The objectives of this research were to record the changes in composition of the community of ephemeroptera in Plalar-Gremeng river, examine the causes of these changes and discover their significance in the life of the rivers. The ephemeropteran community and abundance of the feeding group （detritivore, gatherer and scrapper） were compared with the nutrient and water quality of each sampling site. It is established that, under site conditions, nutrient status can be regarded as the chief internal factors. The method was field survey for sampling the substrate at five sites： （I） Up-stream of Plalar river; （2） The site before the Plalar cave; （3） The total dark zone of Plalar-Gremeng caves; （4） The site after Gremeng cave and （5） The down-stream of Gremeng to Beton river. Substrate sampling used Surber benthic sampler and the sample was containing and labeling. Environmental parameters were measured water temperature, carbon dioxide, velocity, pH, C-organic, sediment total-phosphorus and nitrogen and Ca content. The data was analyzed by description. The results showed that the abundance of ephemeroptera was highest at site-4 and the lowest at site-3. Ephemeropthera play a highly important role in preserving nutrient status.
