• Ocean Science Journal
• /
• 제42권3호
• /
• pp.135-152
• /
• 2007

The ecological aspect of meiofaunal communities in Can Gio mangrove forest, Ho Chi Minh city, Vietnam has not been investigated before. The composition, distribution, density and biodiversity of meiofaunal communities were studied along an intertidal transect at the Khe Nhan mudflat. Each time, three replicate samples were collected in four stations along a transect following the water line from low tide level up to the mangrove forest edge. In total, 18 meiofaunal taxa were found with the dominant taxa belonging to Nematoda, Copepoda, Sarcomastigophora and Polychaeta. The densities of meiofauna ranged from $1156inds/10cm^2$ to $2082inds/10cm^2$. The increase in densities from the mangrove forest edge towards the low water line was significant Along the mudflat transect, the biodiversity (expressed by different indices) was relatively high at different taxonomic levels but did not vary significantly along the mudflat except for taxa richness. Eighty nematode genera belonging to 24 families with Comesomatidae having the highest abundance 33.8 % were found. Theristus and Neochromadora decreased in densities from the lower water line towards the mangrove forest edge, while Paracomesoma and Hopperia are typical and more abundant at the middle of the mudflat. Halalaimus increased from high on the mudflat to the low water line.

• 한국환경과학회지
• /
• 제27권11호
• /
• pp.1007-1021
• /
• 2018

Community dynamics of benthic macroinvertebrates and biological evaluation of water quality were investigated at Gigyecheon of Pohang and Gyeongju, Korea. The survey was carried out at 8 sites from May to October, 2017. As a result, total of 104 species under 54 families, 15 orders, 8 classes in 4 phyla with 5,052 individuals were revealed. The number of species was the most abundantly identified in aquatic insects, 76 species under 34 families, 6 orders. Among them, the order Odonata was the most abundant taxon as 21 species(20.2%). The most abundant individuals were collected in the phylum Mollusca as 1,453 individuals(28.8%). Various species appeared dominantly at each site by season, and the most dominant species was Caridina denticulata denticulata belonging to the class Malacostraca with 0.08 of dominance index. According to the results of community structure analyses, the diversity and richness indices were the highest at site II, the evenness index was the highest at site I, and the dominance index was the highest at site IV. The number of species and individuals of gathering collectors were the highest among functional feeding groups. Those of sprawlers were the highest among habitat orientation groups. The ESB showed a tendency to change according to season and site, and it was the highest in May at most surveyed sites. The KSI was also somewhat fluctuated according to season and site. From these indices, average biological water quality was evaluated as class II.

• 한국환경과학회지
• /
• 제22권12호
• /
• pp.1551-1559
• /
• 2013

This study was conducted to compare benthic macroinvertebrate communities of urban stream and nature stream in Daegu-si, Gyeongju-si, Gyeongsan-si, Andong-si, and Cheongsong-gun. The survey was carried out with 12 points in total six points for urban stream, six points for nature stream from Sept. 2011 to July 2012. In the urban stream were 33 species belonged to 24 families, 11 orders, 7 classes and 4 phyla while in the nature stream were 73 species belonged to 38 families, 12 orders, 5 classes and 4 phyla. In general, species diversity indices and species richness indices appeared low in urban stream but dominance indices was high. Functional feeding groups and Habitat Oriented Groups appeared comparatively simple in urban stream rather than nature stream. As a result of analysis of community stability, species included to area I and area III equally appeared in nature stream while species included to area I mostly appeared in urban stream. An analysis of the correlation between the population density and the number of species, the population number and biological indicators such as DI, H', RI, and ESB revealed that there was a significant correlativity with the diversity index and a very high correlativity with the number of species, abundance index and the ESB. On the other hand, the population number and the dominance index did not reveal any correlativity. For indicator species, Hydroptila KUa, Physa acuta appeared in urban stream while Paraleptophlebia chocolata, Epeorus pellucidus appeared in nature stream.

• 한국제4기학회지
• /
• 제13권1호
• /
• pp.91-98
• /
• 1999

부유성 유공충의 상대적인 양이 고기후 및 고해양환경의 해석에 미치는 영향을 1년 동안 관찰한 퇴적물 포집장치에 함유된 유공충의 연구로 행하여졌다. 본 연구는 저자들이 알고 있는 한 처음으로 행해진 것이다. 총 부유성 유공충의 수, 고기후의 지시자로 사용되는 부유성 유공충 G. bulliodes와 N. dutertrei)의 상대적인 양, 수온, 염도 등은 부유성 유공충 유생의 상대적인 양과 통계적으로 의미 있는 상관관계를 보이지 않는다. 하지만 부유성 유공충 유생의 상대적인 양은 종다양성지수(종 풍성도, 샤논-와이너 지수, 균등도)와 상관관계를 보인다. 이러한 결과는 유생의 양은 종의 상대적인 양에는 영향을 미치지 않으나 종다양성에는 영향을 미침을 의미한다. 따라서 퇴적물 포집장치에서 일년간 관찰한 결과에 의하면 부유성 유공충의 유생을 count 시 제외했을 때 종다양성 지수를 이용한 고기후/고환경해석시 주의 가 요망된다.

• 한국수산과학회지
• /
• 제49권3호
• /
• pp.385-392
• /
• 2016

Seasonal variability in the algal community structure of intertidal zones was examined at six study sites in Marine National Parks, on the western and southern coasts of Korea from March to November 2015. A total of 193 species of algae, comprising 27 green, 40 brown and 126 red algae, were identified. Algal biomass averaged 101.50 g dry wt./m² with a maximal at Tonggae (168.12 g dry wt./m²) and minimum at Haseom (54.49 g dry wt./m²). The dominant seaweeds by biomass were Sargassum thunbergii at five sites (Tonggae, Haseom, Namdongri, Ando amd Sinjeonri), and S. fusiforme at Soando. Community indices measured as follows: dominance index (DI), 0.31–0.69; richness index (R), 7.30–11.43; evenness index (J'), 0.33–0.49; and diversity index (H'), 1.15–1.86. As evaluated using community indices and environmental states, the EEI (Ecological Evaluation Index) of the Marine National Park was “normal”. The present results indicate that seaweed community structures and indices could be used to evaluate the environmental status of coastal ecosystems.

• 한국물환경학회지
• /
• 제34권5호
• /
• pp.514-536
• /
• 2018

GPI (Group Pollution Index) using 29 indicator groups of Korean benthic macroinvertebrates was proposed in 1992, a higher category taxa-level index developed for rapid field assessment of organic water pollution. This study was performed to revise the assessment scheme of GPI based on taxonomic performance and ecological information accumulated since 1992. The original GPI was renamed SBMI (Simple Benthic Macroinvertebrates Index), and SBMI was based on saprobic valency of 26 indicator groups composed of higher category taxa (mainly family ~ phylum) excluding some genus or species-level taxa. SBMI revealed highly significant correlation with concentration of 5-day biochemical oxygen demand ($BOD_5$) (correlation coefficient r = 0.78, n = 569 sites), total suspended solids (r = 0.69), and total phosphorus (r = 0.77). Also, SBMI revealed strong correlation with Shannon-Weaver's species diversity (r = -0.85), Margalef's species richness (r = -0.85), and McNaughton's dominance (r = 0.83). Determination coefficient of SBMI to concentration of water quality items and values of community indices such as species diversity was 3 ~ 8 % and approximately 11 ~ 14 % higher than that of GPI, respectively. Correlation between SBMI and water quality factors or community indices such as species diversity did not reveal much difference compared to that of species-level indices, such as BMI (Benthic Macroinvertebrates Index) and ESB (Ecological Score of Benthic Macroinvertebrates). SMBI is a simple-qualitative index with higher category taxa easily identified, and is applicable for rapid field assessment of water environment impairment.

• 한국수산과학회지
• /
• 제44권6호
• /
• pp.740-746
• /
• 2011

Subtidal benthic macroalgal flora and community structure on barren grounds were examined seasonally along vertical shore gradients on the rocky shore of Hajung, Pohang, on the southeast coast of Korea, from February 2005 to November 2006. Twenty-six seaweed species were identified, including 5 green, 7 brown, and 14 red algae. The number of seaweed species ranged between 7 and 17 among seasons and between 13 and 20 species were found in vertical gradients along the shore. Over the study period, average seaweed biomass (g wet wt/$m^2$) was 299.88 g and it ranged seasonally from 120.99 to 620.00 g. Seaweed biomass declined with increasing seawater depth and ranged between 323.06 and 593.68 g. The dominant seaweed species, in terms of biomass, were Desmarestia ligulata and Sargassum honeri, which grew at depths between 5 and 10 m. The red alga Delisea pulchra was also abundant at a depth of 15 m. No seasonal patterns were found in community indices. Along vertical shore gradients, community indices showed different patterns; the dominance index increased and the richness, evenness, and diversity indices decreased with seawater depth.

• 한국환경생물학회:학술대회논문집
• /
• 한국환경생물학회 2004년도 학술대회
• /
• pp.23-23
• /
• 2004

Four times of field survey were carried out to collect fish samples at six stations in Shinpo district, North Korea in October 1997, July 1998, May and October 2002. Sampling stations were located in upstream, middle and down of the southern river of Bukchong and three brackish lakes of lake Hommanpo, Daein and Hyunkum, respectively. A total of 29 species belonging to 11 families occurred. Family Cyprinidae showed the prosperity in species number of 28% among total species occurred. No natural monument fishes or rare species were captured. Ten commercial fishes, five anadromous ones and five brackish ones were identified. Feeding habits divided fish fauna with 11 carnivores, two herbivores and seven omnivorous ones. In the river, 20 species belonging to seven families inhabited, 18 species of 6 families in lake Homanpo, 21 of seven III Hyunkum and 23 of eight in Daein, respectively. Ecological indices of richness, diversity and evenness were highest in lake Daein and dominance index was highest in lake Hyunkum.

• 생태와환경
• /
• 제43권4호
• /
• pp.477-491
• /
• 2010

Benthic macroinvertebrates were collected two times from 116 sites at the $1^{st}{\sim}4^{th}$ order streams in forest areas in Gyungsang province in late spring and late summer. The sample sites belonged to slightly and moderately polluted states. When communities were classified by the Self-Organizing Map (SOM), the gradient was observed according to degree of pollution. Within clusters of slightly polluted sites, however, seasonality was further observed. Scrapers, gatherer-collectors, and filterer-collectors were abundantly observed in late spring while shredders appeared more in late summer. The number of predator species increased in late summer. Behavior types were mostly clingers in two seasons. Community compositions at the moderately polluted sites were not much differentiated in different seasons. Gatherer-collectors and burrowers were dominantly collected in both seasons.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 G
• /
• pp.2312-2314
• /
• 1998

To improve the visual servoing performance, several strategies were proposed in the past such as redundant feature points, using a point with different height and weighted selection of image features. The performance of these visual servoing methods depends on the configuration between the camera and object. And redundant feature points require much computation efforts. This paper proposes the visual servoing m based on the disturbance observer, which compe the upper off-diagonal component of image fe Jacobian to be null. The performance indices su sensitivity for a measure of richness, sensitiv the control to noise, and controllability are sho improved when the image feature Jacobian is giv a block diagonal matrix. Computer simulation carried out for a PUMA560 robot and show results to verify the effectiveness of the pro method.