Behavioral reaction can be measured as a sensitive endpoint for sublethal toxicity of copper, and can be used to obtain easily and quickly. Also behavioral endpoints may serve as a more insightful evaluation tool of the ecological effects of toxic chemicals. In this study, four invertebrates in freshwater which are usually used indicate species for water quality were selected as test species (Chironomus riparius, Heterocypris incongruens, Daphnia magna, and, Triops longicaudatus). Each test species was exposed to copper for 6 hours, and total distance, velocity, and, turn angle were measured for 1 hour using video analysis system (Ethovision : Noldus Information Technology) in laboratory condition. Each endpoints reflected effect of copper toxicity appropriately for all test species. These endpoint have possibility that can be used to identify characteristic behavioral responses to a metal toxicity. We viewed this study as a preliminary experiment for future research to investigate the significance of behavioral endpoints to various toxic chemicals.

To investigate the trophic relationship between the fresh water fishes and aquatic invertebrates, the research of their prey is important. However, the morphological identification of the prey in the fish intestine is very difficult due to the process of digestion. Thus, we conducted the DNA barcoding methods for aquatic insect samples from the gut of fresh water fishes for identifying hardly recognizable species. All benthic macroinvetebrates and manchurian trouts were collected from the upper streams of Inje-gun, Korea, in spring and summer, 2013. A total of 27 unique taxa were recognized, among which 23 species were identified by morphology, and 4 unrecognizable individuals were identified based on mitochondrial cytochrome C oxidase I (Mt-COI). As the results of this study, Ephemerella sp., Neophylax sp., Neophylax sp., and Pteronarcys sp. are verified to the genus level by DNA barcoding.

Traditionally oxygen demands and concentrations of variable pollutant have been used for the assessment of lentic or lotic water quality. But there is a high probability that newly synthesized chemicals flow into the aquatic ecosystem, and it is very hard to investigate that many kinds of chemicals interact even though they exit at lower level than legal standards. As a consequence of limitation of chemical assessment for media, biological assessment techniques for accepters which are affected by pollutants or physicochemical properties have been developed. However, it still has several weak points because it does not have the ecological relevances using the internationally standard test species which do not inhabit Korea. Besides, the assessment using just one or two species may have a possibility of overestimation or underestimation because a certain species can be extremely sensitive or insensitive to a certain chemical or physicochemical property. Therefore, we used four kinds of indigenous aquatic invertebrates to assess the local stream quality and integrated their responses into a new index which ranges from 0(bad) to 1(good). We assessed four streams throughout Ansan and one stream in Gapyeong, and index values of two streams near residential and industrial area in Ansan were under 0.9 and the others were over 0.9.