• 한국해양학회지:바다
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• 제8권3호
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• pp.243-250
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• 2003

본 연구는 경기만 동물플랑크톤 군집의 시공간적 분포 특성을 파악하기 위하여 2001년 2월부터 2001년 12월까지 인천 연안에서 선갑도에 이르는 수역에서 5개 정점을 대상으로 월별 조사가 실시되었다. 연구 기간중 출현한 동물플랑크톤 개체수는 월평균 1,100∼404,200 indiv./㎥의 범위로 2월에 가장 적은 개체수가 출현하였고 8월에 가장 많은 개체수가 출현하였으며 연구 기간 평균 개체수는 55,000 indiv./㎥였다. 정점별 평균 개체수는 인천 연안 수역에서 114,600 indiv./㎥로 가장 많았고 외해쪽으로 갈수록 감소하여 선갑도 부근 수역에서 16,500 indiv./㎥가 출현하였다. 경기만에서 우점하여 출현한 동물플랑크톤은 Noctiluca scintillans, Acartia hongi, Oithona davisae, Paracalanus crassirostris, Paracalanus indicus, Oikopluera spp. 였으며 이들에 의해 전체 평균 동물플랑크톤 개체수의 94.9％가 점유되었다 대부분의 우점종들은 경기만에서 연중 넓게 분포하지만 계절에 따른 개체수의 대량 증가 현상은 내만 수역에서 집중되는 현상이 나타났으며 이러한 시, 공간적 분포 특성은 수온과 식물플랑크톤 현존량에 의해 크게 영향을 받는 것으로 판단된다.

• 한국환경생태학회지
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• 제22권3호
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• pp.320-324
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• 2008

본 연구는 지리산국립공원에서 번식기동안 산림환경에 따른 번식조류들의 풍부도를 조사하여, 번식조류 풍부도에 영향을 미치는 요인들을 밝히고 조류서식지의 효과적 관리를 위한 기초 자료를 얻기 위해 실시하였다. 조사를 위하여 주등산로 4개소를 조사지로 선정하고 2007년 4월부터 8월까지 번식조류 및 산림환경 조사를 실시하였으며 그 결과는 다음과 같다. 지리산국립공원의 고도 300m부터 1900m에서 번식기동안 관찰된 조류는 총 33종이었으며, 전체 조사지점의 30%이상에서 출현한 13종과 종풍부도, 개체수풍부도로 회귀분석을 실시하였다. 단순회귀분석과 다중회귀분석으로 산림환경 인자들 중 조류들의 풍부도에 영향을 미치는 인자들을 분석한 결과 각 종들은 고도의 영향을 적게 받는 것으로 나타났다. 산림환경 인자들 중 교목층 12m이상 엽층피도율, 수구 관목층 엽층피도율, 경사도, 아교목층 4-2m 엽층피도율 등은 고도보다 더 많은 종의 풍부도 변화에 영향력 있는 인자들로 나타났다. 그러므로 지리산국립공원 번식기 조류의 보호 및 관리를 위해 교목층 12m이상 엽층피도율, 수고, 관목층 엽층피도율, 경사도, 아교목층 4-2m 엽층피도율 등의 유지 관리가 필요하다.

• 환경생물
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• 제35권4호
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• pp.566-572
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• 2017

2015년 10월부터 2016년 7월까지 가을, 겨울, 봄, 여름의 계절별로 한강 하구의 시암, 성동, 공릉천, 산남, 장항습지 등 5개 습지에서 동물플랑크톤 채집을 실시하였다. 25종의 윤충류를 포함하는 총 46종류의 동물플랑크톤이 출현하였다. 기수종은 요각류 2종만이 출현하였고 10월에 성동과 장항습지에 출현한 15종류가 가장 다양하게 출현한 것이었다. 최대 출현량은 3월에 시암습지에서 윤충류의 대량 출현에 의해 $8,000indiv.\;L^{-1}$로 기록되었다. 3월에는 다른 정점에서도 $5,000indiv.\;L^{-1}$ 이상의 높은 출현량이 나타났지만 나머지 기간 중에서 수백 개체의 낮은 밀도가 지속되었다. 종다양성지수는 0.4~1.8 사이에서 변동하였다. 요각류 유생의 장내용물질 분석 결과 미동정물질들과 함께 규조류가 주먹이원인 것으로 밝혀졌다. 수온은 $10.1{\sim}28.2^{\circ}C$, pH는 7.1~8.6 용존산소량은 $4.5{\sim}11.0mg\;L^{-1}$ 사이에서 변동하여 정점에 따라 하계 수온상승에 의한 용존산소량 부족 가능성이 제기되었다.

• The Korean Journal of Ecology
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• 제18권4호
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• pp.441-449
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• 1995

The abundance of coarse woody debris (CWD) has been hypothesized to increase niche for forest dwelling insectivores, concentration of nutrients, and the diversity of invertebrates. However, no abjective assessment based on replication in the field has yet been done. this study was carried out to test the relationships between invertebrate availability and the abundance of four insectivores (Sorex trowbridgii, S. vagrans, S. monticolus and Neurotrichus gibbsii) in western Washington, USA. Pitfall traps were used to determine abundance and diversity of invertebrates. Abundance of insectivores was not different between habitats except for S. vagrans which was more abundant in habitats with low amounts of CWD than in habitats with high amounts of CWD. Simpson’s diversity index computed for invertebrates did not differ between habitats. There were no significant relationships between the diversity indices of invertebrates and the abundance of shrews. Shrew abundance and the Coleoperan beetles also did not show any significant relationship. The results suggested insectivores might select a wide range of prey items in addition to surface-active invertebrates.

• 환경생물
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• 제33권2호
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• pp.223-229
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• 2015

Pre-monsoon dynamics of zooplankton community were investigated in the downstream of the Gagok stream flowing into the East Sea of Korea. Monthly sampling was carried out to collect zooplankters at five sites in the stream during the period between April and July 2014. Dissolved oxygen contents exceeded $7.0mg\;L^{-1}$ all the time. Water temperature was in a range of 15.7 to $24.9^{\circ}C$ and pH 7.4 to 8.8, respectively. A total of 75 taxa consisted of 36 species of rotifers, 16 species of cladocerans, 16 species of copepods, four kinds of aquatic insects, two kinds of decapods and one nematod was occurred. One species of marine copepod and one cladoceran, and one species of brackish rotifer and one copepod distributed at the station located in the stream mouth. Zooplankton abundance showed to vary from 42 to 4202 individuals $m^{-3}$ due to the explosion of aquatic insects and Alona sp. at site 2 located in the downstream in April. Heavy rainfall during the monsoon period seems to decrease the zooplankton abundance caused by diffusion and drifting to the sea. Species diversity indices were generally high between 1.2~2.3 and were recorded to be high at the downstream throughout the study period. With the zooplankton dynamics, the influence of the input of sea waters into the stream seemed to be confined to some hundred meters of the stream mouth facing the East Sea.

• 대한의생명과학회지
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• 제17권4호
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• pp.367-370
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• 2011

Studies on the relative abundance of potential vectors of scrub typhus was conducted from April to October 2009 at the Jangseong of Jeonnam Province, Korea. Among the total 62 field rodents collected by the Sherman collapsible traps, 56 rodents were $Apodemus$ $agrarius$ (90.3%), 4 were $Crocidura$ $lasiura$ (6.4%) and 2 were $Cricetulus$ $triton$ $nester$ (3.2%). Out of the 62 field rodents, 39 were parasitized by chiggers, showing 62.9% of the infestation rate and 80.0 of the chigger index. Chigger index of $A.$ $agrarius$ and $C.$ $triton$ $nester$ were 79.9, 82.0, respectively. But chigger mite was not collected from $C.$ $lasiura$. From the trapped field rodents, 3,120 chiggers were collected and identified with 6 species of 2 genera. $Leptotrombidium$ $scutellare$, the vector species of tsutsugamushi disease, was the dominant species, showing 2,276 chiggers (72.9%). $L.$ $pallidum$ was the second dominant species showing 346 chiggers (11.0%). The distribution of chigger mites was showed the different dominant species according to seasons. $L.$ $pallidum$ was the predominant chigger collected in April (34.8%), May (77.8%) and Jun (39.3%), whereas $L.$ $scutellare$ was the predominant chigger collected in September (78.78%) and October (76.8%).

• 한국수산과학회지
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• 제50권5호
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• pp.553-560
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• 2017

Fluctuations in the abundance and species composition of fishes in the coastal waters of Geumo-do, Yeosu, Jeollanam-do, Korea were investigated from 2002 to 2005. A gill net with entrances on both sides was used to collect a total of 469 individuals (55,180 g) of 3 orders, 18 families, and 28 species. The dominant species was Sebastes inermis (60 individuals, 5,670 g), followed by Neoditrema ransonneti (46 individuals, 2,290 g), and Pseudaesopia japonica (38 individuals, 3,080 g). The highest number of individuals was found in 2004, while the biomass was highest in 2005. The diversity index was highest in 2004 (H'=2.703) and lowest in 2002 (H'=2.580). The dominance index was highest in 2004 (D=3.983) and lowest in 2002 (D=3.404). The richness index was highest in 2003 (RI=0.337) and lowest in 2002 (RI=0.261). Changes in temperature and salinity affected the community structure and the location of spawning grounds. The number of individuals and total biomass increased with changes in temperature and salinity each year.

• 한국수산과학회지
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• 제51권4호
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• pp.426-434
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• 2018

We investigated temporal and depth-related variation in species composition and abundance of the fish assemblage in the southern East Sea. Fish samples were collected seasonally between 2007 and 2008 using a demersal trawl off the southern coast of Korea. We identified 59 fish species belonging to 41 families. The most frequently occurring species was Coelorinchus multispinulosus, followed by Lophius litulon, Acropoma japonicum and Apogon lineatus. The five most abundant species were A. lineatus, A. japonicum, Myctophum nitidulum, Engraulis japonicus and C. multispinulosus, accounting for 87.04% of the total number of individuals collected. The number of species, abundance and diversity fluctuated with sampling location and time. Permutational multivariate analyses of variance revealed that the assemblage structure was influenced by year, season and water depth, with season being the main indicator. These changes were visually emphasized using non-metric multidimensional scaling ordination plots. Fluctuations in assemblage structure were due to differential contributions of the dominant species.

• 농업과학연구
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• 제39권4호
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• pp.545-553
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• 2012

In Asia, including Japan and Korea, rice paddies occupy the largest cultivated area in agricultural land. Rice paddies provide the habitats for many organisms including endemic species, sustaining high biodiversity. Insect natural enemies inhabiting rice paddies have an important function for rice production as agents of 'ecosystem services' because they play a major role in suppressing rice pests. The diversity and abundance of natural enemies can be a good index reflecting the 'healthiness' of agro-ecosystem services in rice paddies. The present study investigates whether insect natural enemies could be good biological indicators for general arthropod biodiversity and agricultural practice. First, the concept of ideal bio-indicators was summarized. The strategy to explore and select such bio-indicators was then proposed. Lastly, field survey was made to evaluate the abundance and biodiversity of natural enemies in Japanese rice paddies where chemical inputs, i.e., insecticide use, were different. The results showed that reduction of chemical inputs led to an increase in species richness or diversity of natural enemies including parasitoids and predators. Then, the data were analyzed to examine suitable indicator species to assess environmental soundness of agricultural practice and biodiversity in rice paddies. The density of several species of natural enemies did respond both to pesticide use and to general arthropod biodiversity. The analyses thus have indicated that natural enemies can be suitable as bio-indicators. Usefulness of indicator species in rice paddies is discussed in the context of ecologically sound agriculture.

• 한국유기농업학회지
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• 제3권1호
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• pp.23-42
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• 1994

This paper studied earthworm populations in fields under practical cultivation in the Eastern Harzforeland (Germany). The examined sites differed insignificantly in their climatic and soil conditions. The examination was a comparison between a field and a narrow edge or meadow. A combination of Oktett method and handsortin was used. The five different habitates seven earthworm species were discoverd. The most frequently foundd were A. rosea, A. caliginosa, and A. chlorotica. There were clear differences in species between the habitates of each site. Generally the edge or the meadow contained one (Zoeberitz) or two (Zscherben) more species than the field. The composition of species differed between 1990 and 1992. In the dry Autumn of 1991 there were less species found at both sites. The occurance of earthworm species depends on the weather. Moisture influencing similiarity of abundance and bio-mass were recorded in three out of four habitates. Starting on a high level in Autumn 1990 the abundance as well as biomass decreased until Autumn 1991 and increased the following year. The number from 1990 were never reached again during the examination. One year of normal precipita-tion was not enough to return the population to the beginning level. Great differences in the number of earthworms between the compared habitats suggest that the edges and meadows are a potential immigration source into a field which is poor on earthworms. Structrues of distribution near the edge refer to a migration from a high populated edge into an almost empty field.