Suspended solids play an important role in the growth and survival of aquatic organisms. The marine zooplankton species tested in this study were Tigriopus west (Copepoda) and Haustorioides koreanus (Amphipoda) sampled from the intertidal zone, including Artemia nauplii (Branchiopoda) hatched from cysts. The study design included six concentrations (0, 50, 100, 250, 500, and 1,000 mg L-1) of the suspended test particles assayed in triplicate. Experimental cultures in 500 mL-round polycarbonate bottles were subsampled after 96 h to count dead zooplankton. The culture bottles were agitated at 4 RPM on a rotating wheel at 23°C and 30 PSU. The survival rates of Artemia nauplii and T. west were not affected by suspended solid concentrations higher than 50.0 mg L-1, whereas the survival rate of H. koreanus decreased with increasing concentrations (p<0.05). In conclusion, H. koreanus and T. west, which were continuously exposed to suspended solid concentrations higher than 50.0 mg L-1, were affected by low-intensity ecological stress. However, in the case of H. koreanus, a concentration of 50.0 mg L-1 may be considered to be the limit of tolerance to suspended solids, suggesting that the number of individuals who eventually die will increase if continuously exposed.
In this study, the community structure of marine benthic invertebrates was examined to evaluate the differences between the west, south, and east coasts of Korea and to identify the indicator species representing each region. Acrylic attachment plate sets were installed in Jeongok, Mokpo, Tongyeong, Yangpo, and Gangreung, and the invertebrate fauna thus captured were identified. Monitoring was performed in each area from March 2017 to May 2018. Water depth, temperature, and salinity at each location were measured to determine the potential influence of abiotic factors on the community structure. As a result, the mean depth of plates installed and the water temperature were significantly different in each area. A total of 32 invertebrate species were identified in all localities, and the most significant difference in the species compositions was found between Mokpo and Gangreung. The community structure differed significantly with a change in the plate depth, and a larger number of indicator species appeared on shallower plates. Finally, we determined the community structure of benthic invertebrates in different geographical regions of the Korean ocean by characterizing the dominant invertebrate taxa and the indicator species at each site.
농업생태계에 따른 지표배회성 무척추동물의 군집 특성을 비교하기 위하여 한반도 동부의 3개 행정권역내에 분포하는 논, 밭, 과수원을 대 상으로 선정하였다. 2013년부터 2015년까지 매년 2회에 걸쳐 pit-fall trap법을 사용하여 채집된 무척추동물을 통해 군집분석을 하고 기상자료를 포함하는 환경요인의 영향을 분석하였다. 전체 채집된 무척추동물은 13목 58과 172종 6,420개체이며, 분류군 중에서 벌목(38.26%), 메뚜기목 (16.28%)이 우점하였다. 경상남도 출현 개체수가 2,983개체(46.46%)로 가장 많았으며, 경상북도가 풍부도(1.96), 다양도(1.51) 모두 높게 나타 났다. 농업생태계 유형 중 논에서 69종 3,299개체(51.39%)가 조사되었으며, 종다양성 지수도 높게 확인되었다. 특히 우점종인 개미과의 포함유 무가 종 다양성지수 분석에 미치는 영향은 미미한 것으로 보여진다. 곤충 분류군과 환경요인과의 정준상관분석 결과, 토양 pH, 토양온도와 토양 함수율의 영향에 의해 매미목, 바퀴목, 흰개미목, 딱정벌레목과는 양의 상관관계로 구분되었고, 기온, 강수량, 전기전도도, 상대습도, 최저초상온 도와는 음의 상관관계를 나타냈다. 무척추동물 군집은 계층적 군집화를 통해 생태계 유형별로 패턴화가 일어나는 것으로 확인되었다. 이러한 결 과는 공간과 환경요인과의 상관관계가 무척추동물의 분포에 다소 영향을 주는 것으로 사료된다.
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.
다도해해상국립공원의 비금.도초지구인 우이도 해역의 조하대에 서식하는 대형무척추동물의 생물다양성, 생물량(개체수 및 생체량) 및 군집구조를 파악하기 위하여 2008년 5월과 9월에 현장조사를 실시하였다. 조사 기간 중, 총 63종 1.4 m-2, 3,750개체(268 inds. m-2)와 156.14 gWWt (11.15 gWWt m-2)의 대형무척추동물이 출현하였다. 출현 종수, 개체수 및 생체량에 있어서 환형동물문의 다모류가
Analysis of benthic micro-invertebrate community structure from the Pyeonghwaui Dam was investigated from May 2006 to October 2008. Total taxa of benthic micro-invertebrates were 5 phylum, 8 class, 15 order, 44 family, and 97 species in 2006, and 5 phylum, 7 class, 15 order, 48 family, 103 species in 2008. Mean dominance index at St. 1 to St. 5 were 0.36, 038, 0.38, 0.21 and 0.29. Mean species diversity at St. 1 to St. 5 were 3.84, 3.34, 3.13, 4.84 and 4.28. Although the dominance index of Lentic area was higher than Lotic, but the diversity was lower than Lotic area.
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.
This study was conducted to compare the community structure and biodiversity of ground-dwelling invertebrates between conventional and organic paddy fields’s levees. Ground-dwelling invertebrates were collected using a pitfall trap every month for two years (2010-2011) in levees of conventional and organic paddy fields. The numbers of species and individuals were higher in organic paddy field than in conventional paddy field. For the pests, the treatment of insecticide and herbicide reduced the number of Delphacidae, and Chrysomelidae, but did not affect the other pests such as Chronomidae, Culicidae, Thripidae, and Aphididae. For the natural enemies, the treatment reduced the number of individuals of most of enemy's taxon (except only one taxonomic group, Ichneumonidae) in the levee of conventional paddy field.
We have studied characteristics of community structure on the benthic macro-invertebrates at twelve selected sites in upstream, midstream and downstream of Paemsagol, Piagol, Chilseongol and Daeseonggol, major streams of Jirisan Mountain, for three years from April 2008 to September 2010. As a result, 2 phyla, 3 classes, 11 orders, 41 families, 119 species and 4,449 individuals of benthic macro-invertebrates have been collected and classified in this study. Among them EPT group (Ephemeroptera, Plecoptera, Trichoptera), commonly appearing taxa in clean stream ecosystem, was found most frequently. The highest species number of benthic macro-invertebrates were collected in 2008, the year with lower climatic influence including heavy rain. In almost all of survey sites 80% or over of EPT group were counted, and St. 1 scored highest rate of EPT group at 92.59%. Most dominant species was Ecdyonurus kibumensis at 12.83% of dominance index, and subdominant species was Goerodes KUb at 6.81% of dominance index. The investigation of the feeding function group indicated that gathering-collectors were dominant with 26 species and 1,334 individuals, while the number of filtering-collectors was lowest with 11 species and 230 individuals. This result represents that the feeding function group of Jirisan Mountain is mountainous stream-specific one. Both diversity index and richness index were lowest at the midstream of Chilseongol (St. 5), while the midstreams of Daeseonggol (St. 11) and Piagol (St. 8) were highest in diversity and richness indices respectively. The analyses of linear regression and correlation were performed in order to investigate and to predict the appearance aspect of EPT group by altitude. The results showed that the ratio of Plecopteran species number has increased by the elevation of the altitude at 0.05 significance level. Cluster analysis was also carried out for evaluating environmental similarities among survey sites. As a result, upper regions of Paemsagol (St. 1) and Piagol have clustered as most similar sites each other, while the midstream of Piagol (St. 8) has separated with lower similarity value than other sites in species composition.
Chronic effects such as reproduction and population dynamics with elevated CO2 concentration were evaluated using two representative marine benthic species, copepod (Tisbe sp.) and amphipod (Monocorophium acherusicum) adopting long-term exposure. Juvenile copepod and amphipod individuals were cultivated in the seawater equilibrated with control air (0.395 mmol CO2/air mol) and high CO2 air having 0.998, to 3.03, 10.3, and 30.1 mmol CO2/air mol during 20 and 46 days, respectively. After the exposure period, the number of benthic invertebrate was counted with separate larval and juvenile stage such as naupliar, copepodid and adult for copepod, or neonate and adult for amphipod, respectively. The individual number of both test species at each life-stage was significantly decreased in seawater with 10.3 mmol CO2/air mol or higher. Recently, the technology of marine CO2 sequestration has been developed for the reduction of CO2 emission, which may cause climate change. However, under various scenarios of CO2 leaks during the injection process or sequestrated CO2 in marine geological structure, the potential risk to organism including various invertebrates can be expected to exposure. So the results of this study suggested that the detailed consideration on the adverse effect with marine ecosystem can be prerequisite for the marine CO2 sequestration projects.