• Title/Summary/Keyword: Diversity indices

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Wintering Bird Community in Cheonsu Bay and the Relationship with Food Resources (천수만에서 월동하는 조류군집과 먹이 자원과의 관계)

  • Yoo, Seung-Hwa;Kim, In-Kyu;Kang, Tae-Han;Jo, Hae-Jin;Yu, Jae-Pyoung;Lee, Si-Wan;Lee, Han-Soo
    • Korean Journal of Environment and Ecology
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    • v.22 no.3
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    • pp.301-308
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    • 2008
  • We conducted the survey about the avian fauna, population, community and correlation between avian population and densities of the fallen rice grain in Cheonsu reclaimed area(Ganwol and Bunam Lake and reclaimed land) from Oct. 2006 to Mar. 2007. Total surveyed species number was 142 species, sum of maximum count of each species was 362,797 individuals, sum of average count of each species was 84,818 individuals. Comparing with early and late wintering season, number of species was stable in each survey time, but total population was decreased as the season progressed. Dominant species were Bean Geese Anser fabalis, Baikal Teals Anas formosa, White-fronted Geese Anser albifrons, Mallards Anas platyrhynchos and Pintails Anas acuta. Population fluctuation of the Bean Geese Anser fabalis, Baikal Teals Anas formosa, Mallards Anas platyrhynchos, PintailsAnas acuta was decreasing, but population of the White-fronted Geese Anser albifrons was stable. Number of species, total population were not significantly different among Ganwol, Bunam and Cheonsu Bay. Survey period was significantly correlated with species diversity and population in each area, and most community indices of each area were shown significant correlation. The density of the fallen rice grain was significantly different between the harvested rice paddy by big harvesting machine and small harvesting machine. Density of the fallen rice grain in stubble collected area was significantly different with area of stubble not collected. Density of the fallen rice grain was drastically decreased in the middle of wintering season, but not significantly different between Dec. 2006 and Feb. 2007. Avian population was strongly correlated with number of fallen rice grain in the same period.

Seasonal Changes on Community Structures of Benthic Macroinvertebrates in Wetland Upo (우포늪 저서성 대형무척추동물의 계절별 군집구조 변화)

  • Lee, Jun-Cheol;Koo, Bon-Yoon;Yoon, Chun-Sik;Lee, Dong-Jun;Cheong, Seon-Woo
    • Journal of Environmental Science International
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    • v.20 no.2
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    • pp.261-274
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    • 2011
  • The studies on community structure of benthic macroinvertebrates and environmental survey in selected four sites were performed on wetland Upo from 2008 to 2009. The lowest water temperature was measured at Upo and Mokpo showing $7^{\circ}C$ in February of 2008 and 2009 respectively. The highest water temperature was measured at Upo showing $32^{\circ}C$ in August of 2009. The lowest pH was measured at Topyeong with 5.3 in August of 2009, and the highest pH was measured at Mokpo with 10.1 in August of 2008. Generally the levels pH of 2008 were higher than those of 2009. The range of electric conductivity to the sites was big. Overall, the higher electric conductivity was seen at Sajipo and the lower one was seen at Mokpo. The level of Dissolved oxygen was lowest at Upo with $5.53mg/\ell$ in August 2008, and it was highest at Upo with $14.76mg/\ell$ in February of 2008. The investigation was performed with both quantitative and qualitative collecting methods from four surveying sites, Upo, Mokpo, Sajipo and Topyeong. Through the eight times of seasonal survey, 6 classes, 17 orders, 59 families, 131 species and 5460 individuals of benthic macroinvertebrates were collected. 6 classes, 17 orders, 53 families 106 species and 2439 individuals were identified in 2008, and 6 classes, 16 orders, 44 families, 93 species and 3021 individuals were collected in 2009. The number of species was decreased in 2009 comparing that of 2008, however, the number of individuals were increased in 2009. The dominant species and the subdominant species was Plea (Paraplea) indistinguenda and Diplonychus esakii with 20.16% and 11.90% of dominant indices respectively. From the community analysis, both the species diversity index and the species richness index were highest in Topyeong showing 4.743 and 9.054 respectively. The similarity evaluation to the investigation sites with the species in there showed very high similarity among Upo, Mokpo and Sajipo showing 5 or lower levels of distance cluster combine.

Temporal and Spatial Changes in the Species Composition and Abundance of Benthic Polychaetes after the Construction of Shihwa Dike (West Coast of Korea) (시화 방조제 건설 이후 시화호 다모류의 종 조성 몇 서식밀도 변화)

  • Ryu, Jong-Seong;Choi, Jin-Woo;Kang, Seong-Gil;Koh, Chul-Hwan;Huh, Sung-Hoi
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.2 no.2
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    • pp.101-109
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    • 1997
  • The present study was carried out to investigate the temporal and spatial changes in species composition and abundance of polychaetes in Lake Shihwa. Macrobenthic fauna were collected from eight sampling surveys performed in March, June, September and December of 1994, March and October of 1995, February and August of 1996, using a modified van Veen grab with 0.1 $m^2$ coverage area. Polychaete worms, the most abundant macrofaunal group, comprised of 1~22 species at each investigation; number of species continuously decreased during the survey period. The mean density of polychaete was $794{\pm}1,275\;indiv.{\cdot}m^{-2}$ and showed a large fluctuation over time. The variation in abundance was mainly coupled with the domination of Polydora ligni occupying 83% in total density. The next dominant species were Pseudopolydora kempi (mean density of 31 $indiv.{\cdot}m^{-2}$) and Capitella capitata (mean density of 23 $indiv.{\cdot}m^{-2}$). Abundant polychaetes in Lake Shihwa are known to be tolerant to sediment pollution. Ecological indices such as diversity (H') and dominance (D) also indicated that the number of species significantly decreased and a few species predominated in Lake Shihwa after the dike construction. The azoic zone were extended from the upper reach of Lake Shihwa to the vicinity of the dike over time. The reduced number of species, predominance of pollution indicator species and development of an azoic zone reflect severe deterioration of benthic environments in Lake Shihwa.

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A Study on the Freshwater Fish Community in the Small Streams in Namhae Island, Korea (남해도 소하천 담수어류 군집에 관한 연구)

  • Han, Jeong-Ho;Park, Chan-Seo;Hwang, Hosung;Paek, Woon-Kee
    • Korean Journal of Environment and Ecology
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    • v.30 no.4
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    • pp.730-744
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    • 2016
  • In this study, fish fauna and stream characteristics were surveyed from June to October of 2014 in 31 sites of 23 small streams of Namhae Island. During the study period, 38 species belonging to 30 genera under 13 families were collected. Cyprinidae and Gobiidae fish occupied 28.9% (11 species) and Cobitidae fish accounted for 10.5% (4 species). The dominant family was Cyprinidae, and the most dominant species was Zacco koreanus with 30.3% (1,089 individuals) of the total. Eight species (33.8%) such as Zacco koreanus, Squalidus gracilis majimae, Coreoleuciscus splendidus, Pseudobagrus koreanus, Iksookimia hugowolfeld, Iksookimia longicorpa, Silurus microdorsalis and Liobagrus mediadiposalis were Korean endemic and one species of Micropterus salmoides was exotic. According to the analysis of the community based on the diversity, evenness and richness indices, fish community seems to be more stable in the S7. The small streams were classified into three types of steep mountainous, mountainous-flatland, and flat land streams, and their types were categorized by their features of stream width, water depth, bottom substrate, riparian vegetation, and land use patterns. Principal component analysis based on species abundance classified fish communities into three main groups according to human impact and land-use pattern change. These results suggest that fish community structures were primary affected by the longitudinal environmental changes and these were modified by the habitat condition in accordance with the land use pattern change in the small streams.

The Characteristic of Fish Fauna and Distribution by Habitat Type in the Yanghwa Stream of the Namhan River Basins (남한강 수계 양화천의 서식처 유형별 어류상 및 분포특성)

  • Lee, Seung-Hyun;Lee, Hwang-Goo;Shin, Hyun-Seon;Choi, Jun-Kil
    • Korean Journal of Environment and Ecology
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    • v.26 no.6
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    • pp.884-891
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    • 2012
  • The characteristic of fish fauna and distribution by habitat type in the Yanghwa stream were investigated from August, 2008 to June, 2009. During the surveyed period, 30 species belonging 8 families were collected. And there were 10 Korea endemic species(33.3%), including Rhodeus uyekii et and so on. Dominant species was Rhodeus notatus, and subdominant species was Pseudorasbora parva. Dominant species according to habitat type was Pseudorasbora parva in Dam type pool and Channel conected pool, Pseudogobio esocinus(Run), Zacco platypus(Riffle), Rhodeus notatus(Side channel and Substrate type pool), Squalidus gracilis majimae(Meander type pool), and Carassius auratus(Channel unconnected pool), respectively. As a results of community analysis in the Yanghwa Stream, diversity, richness, and abundance indices showed relatively high values, indicating that studied stream have relatively stable community structure. Moreover, cluster and principal component analysis were divided by two groups(lotic and lentic habitats), suggest that species and individuals were different among habitat types.

Terrestrial Insect Fauna of the Junam Wetlands Area in Korea (우리나라 주남습지 지역의 육상 곤충상)

  • Ahn, Soo-Jeong;Park, Chung-Gyoo
    • Korean journal of applied entomology
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    • v.51 no.2
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    • pp.111-129
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    • 2012
  • Terrestrial insect fauna was surveyed in the Junam wetland area, which consists of the Junam, Dongpan, and Sannam wetlands, by visual counting and pictures. A sweep net collection was conducted from May to October 2010. A neighburing artificial lotus wetland was also surveyed for comparison. A total of 5,730 insects were surveyed, representing 268 species in 85 families and 12 orders. Sixty-three species of coleopterans were surveyed, followed by 60 species of Lepidoptera, and 37 species of Hemiptera. Coleopteran individuals were 25.9% of the total insect numbers surveyed, comprising most abundant group. This was followed by Odonata, Lepidoptera, and Orthoptera at 22.3%, 15.4%, and 12.7%, respectively. In total, 197 species were surveyed in the Dongpan wetland, 175 in the Junam wetland, and 154 species in the Sannam wetlands. However, only 86 species were surveyed in the artificial lotus wetland. Galerucella nipponensis in Coleoptera, Crocothemis servilia mariannae in Odonata, and Polygonia c-aureum in Lepidoptera were the most abundant in all four wetlands. Community analyses showed that the dominance index was highest in the artificial lotus wetland at 0.25 and lowest in Junam wetland at 0.08. Diversity indices were relatively high in all wetlands at 4.48, 4.44, 4.28, and 3.87 in Junam, Dongpan, Sannam, and the artificial lotus wetland, respectively. The insect fauna similarity index was highest in the Junam and Dongpan wetlands at 0.96. The lotus wetland showed the lowest similarity of the three wetlands with values of 0.45-0.53.

Effects of Debris Barrier on Community Structure and Functional Feeding Groups of the Benthic Macroinvertebrate (사방공작물의 시공이 저서성대형무척추동물의 군집구조 및 섭식기능군에 미치는 영향)

  • Seo, Jun-Pyo;Lee, Heon-Ho
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.480-487
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    • 2012
  • This study was conducted to search the effects of debris barrier on the benthic macroinvertebrate. Gimcheon was selected as the survey site as it has relatively stable ecosystem with constantly running water. The survey was conducted 6 times before and after the construction of debris barrier from February in 2009 to October in 2010. In the first survey before construction, the identified species were 36 species belonged to 22 families, 9 order, 4 class, and 4 phylum. The figure slightly decreased to 30 species belonged to 18 families, 7 order, 2 class, and 2 phylum in the sixth survey after construction. Before construction, occupation ratio of EPT taxa was showed in the following order: Ephemeroptera (50.0%, 85.0%), Trichoptera (35.3%, 10.0%), and Plecopteran (14.8%, 5.0%). After construction, it was showed in the following order: Trichoptera (50.3%, 68.0%), Ephemeroptera (42.1%, 29.4%), and Plecopteran (7.5%, 2.7%). Ephemeroptera was the highest before construction. Trichoptera increased rapidly after construction. The Diversity, Richness, Evenness, and Dominance indices were all turned low in the second survey right after the construction. However, each index tended to increase with the course of time. In Functional Feeding Groups, GC type was the highest of 60.7% before construction. After construction, SC(53.1%) and FC(35.4%) increased rapidly and they became stabilized since the third survey. The result of this study reveals that debris barrier greatly affects the Aquatic Ecosystem right after its construction, but the system becomes stable and returns to normal with the course of time (about 18 months). Therefore, the study considering various influence factors such as time is required to recover completely through further long-term monitoring.

Prediction of Succession and Silvicultural Control in the Black Locust(Robinia pseudoacacia L.) Plantation (아까시나무(Robinia pseudoacacia L.) 조림지(造林地)에서 천이(遷移)의 예측(豫測)과 조림학적(造林學的) 제어(制御))

  • Yun, Chung Weon;Oh, Seung Hwan;Lee, Joon Hyouk;Joo, Sung Hyun;Hong, Sung Cheon
    • Journal of Korean Society of Forest Science
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    • v.88 no.2
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    • pp.229-239
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    • 1999
  • To get ecological information necessary for the prediction on succession and the silvicultural control of the black locust(R. pseudoacacia) plantation, classification of vegetation unit. competition of major species, and succession were analyzed. The results were as follows. Vegetation units classified in R. pseudoacacia forest were Quercus variabilis community, Persicaria perfoliata community, Styrax japonica community, Acalypha australis community, Typical community. Species diversity indices showed significant difference among the vegetation units. As a result of stand ordination by CCA method, arrangement of stands on Axis I was correlated significantly with altitude, sand, silt and available phosphorus contents, and that on Axis II was with total nitrogen, exchangeable calcium and kalium contents. It was judged that R. pseudoacacia plantation would be replaced by the mixed forest including Quercus spp., Acer spp., and Prunus spp. etc., native to Korea with the progression of succession as the results of analyses on competition of major species and successional tendency in R. pseudoacacia plantation.

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Community Structure and Cluster Analysis of the Benthic Macroinvertebrates in Inflow and Outflow area of Ten Reservoirs of the Nakdong River System (낙동강수계 10개 호소의 유입 및 유출부의 저서성대형무척추동물 군집구조 및 유사도 분석)

  • Lee, Mi-Jin;Park, Jin-Young;Seo, Jung-Kwan;Lee, Hae-Jin;Seo, Eul-Won;Lee, Jong-Eun
    • Journal of Life Science
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    • v.19 no.12
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    • pp.1758-1763
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    • 2009
  • Biological assessments of benthic macroinvertebrates community structure were carried out in ten reservoir inflow and outflow areas of the Nakdong river system from April 2008 to August 2008. The collected benthic macroinvertebrates from the surveyed sites were 9,427.6 inds./$m^2$, 42 species belonging to 29 families and 16 orders. A dominant species was Chironomus sp. and a subdominant species was Ecdyonurus levis. In the all sites, Ephemeroptera had the most number of species (17.81%) and Diptera had the most number of individuals (64.00%). Dominance, species diversity, species richness, and species evenness indexes were 0.68, 2.42, 2.96 and 0.54, respectively. The numbers of benthic macroinvertebrates species in each surveyed site were from 21 (site 9 Jilnal wetland) to 51 (site 2 Yeongcheon reservoir). As a result of an analysis about relative resistance and resilience of stability factors, the most popular group was group I with high indices in both resistance and resilience. Site 7 (Beongae wetland) and site 8 (Jangcheok reservoir) had the highest similarity in the result of cluster analysis using the surveyed benthic macroinvertebrates.

Analyzing the Spatial Change of Urban Green Spaces with Cell Based Spatial Metrics : A Case Study of Daegu (화소 기반 공간메트릭스를 이용한 도시 녹지의 공간적 변화 분석: 대구시를 사례로)

  • Seo, Hyun-Jin;Jun, Byong-Woon
    • Journal of the Korean association of regional geographers
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    • v.23 no.1
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    • pp.136-150
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    • 2017
  • This study analyzed the spatial change of urban green spaces in Daegu from 1989 to 2009 using cell based spatial metrics. To do so, the conversion process of land covers during the past 20 years was explored using a land cover change detection matrix. The synoptic analysis with a moving window sampling strategy was conducted to quantify cell based spatial metrics related to size, shape, cohesion, and diversity and to explain the spatial change at the local level. Difference maps were then generated by subtracting the 1989 maps of spatial metrics from the 1998 maps and the 1998 maps from the 2009 maps. The gradient analysis was performed to identify the directional change of spatial metrics along an urban development axis in Daegu. The results from this study show that urban green spaces in Daegu during the past 20 years have been gradually fragmented around the new town housing development districts such as Dalseong-gun, Seongseo, and Ansim. Forests were most prominently fragmented in the Hwawon area while most rapidly in the Chilgok area. Grasslands were largely fragmented in many areas due to the decrease in size and cohesion indices and most fragmented in the Ansim area. The spatial pattern of the decreased and fragmented urban green spaces identified by this study can be used as a base data for establishing the environment-friendly urban development strategy in Daegu.

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