• Title/Summary/Keyword: 번식 밀도

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Differences in Breeding Bird Communities between Coniferous Forests of Mt. Namsan and Gwangneung Areas (남산과 광릉의 침엽수림에서 번식기 조류 군집의 차이)

  • Rhim, Shin-Jae
    • Korean Journal of Environment and Ecology
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    • v.22 no.3
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    • pp.332-337
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    • 2008
  • This study was conducted to clarify the differences in bird communities in breeding season between coniferous forests of Mt. Namsan and Gwangneung areas from April to August 2006. We chose a study site of 10ha in size for territory mapping of breeding bird community in each area. There were significant difference in DBH distribution of trees and average foliage profiles between both study areas. Number of breeding species and pairs, breeding density, and bird species diversity were higher in Gwangneung area than in Mt. Namsan area. Number of bird species and breeding pairs belonged to hole and canopy guild were different between both study areas. The difference in breeding bird communities between both study areas may be related with forest structure. For the protection and management of birds, greater structural complexity would be needed in Mt. Namsan area.

Selection of Emergent Plants as for the Nesting Site by the Breeding Birds on the Marsh of Paldang Dam and Gyungan-cheon (팔당댐과 경안천 습지에 번식하는 조류의 둥지 장소로서의 정수식물의 선택)

  • Lee, Ki-Sup;Kim, Mi-Ran
    • Journal of Wetlands Research
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    • v.11 no.1
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    • pp.29-37
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    • 2009
  • This study was conducted on the marsh of Paldang dam and Gyungan-cheon, Gyeonggi-do province. 6 species bred on the emergent plants and the nests of Common Coots Fulica atra, Common Moorhens Gallinula chloropus, Great Reed-Warblers Acrocephalus orientalis, Yellow Bitterns Ixobrychus eurhythmus, Little Grebes Podiceps ruficollis and Great Crested Grebes Podiceps cristatus were found. The main vegetations of the nests were Narrow Leaf Cattails Typha angustata, Reeds Phragmites communis, and Wild Rices Zizania latitolia. Particularly, Narrow Leaf Cattails were the most favorite plants for breeding birds. Few nests were found on the emergent plants covered with rubbish, or on high density. And no nests found on the inside shrubs. The mean density of nests on the marsh was 3.1 nests per ha and the nests were highest in Non-island as 17 nests per ha. The nest density on the area of Sonae-islands was higher than the area of Kyangdong-kyo bridge. This would be related on the bulk of narrow-leaf cattails and the quality of water.

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Effect of Fishing Activity on Nest Selection and Density of Waterfowls in Namyang Lake (낚시꾼의 활동이 수초 지대에 번식하는 물새류의 둥지 위치 선택과 밀도에 미치는 영향)

  • Park, Ji-Hwan;Park, Heon-Woo;Sung, Ha-Cheol;Park, Shi-Ryong
    • Journal of Ecology and Environment
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    • v.29 no.3
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    • pp.213-217
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    • 2006
  • The increase of human activities has been extensively changed the breeding habitats of birds directly or indirectly, where the reproductive success of the birds has been seriously reduced. Leisure activities on water, such as fishing, influenced the breeding biology of waterfowls. However, few researches have been done for this in Korea. We examined the effects of fishing activity on nest selection and density of four waterfowl species at Namyang Lake: Coot (Fulica atra), Moorhen (Gallinula chloropus), Little Grebe (Podiceps ruficollis), and Great Crested Grebe (Podiceps cristatus). We divided the Namyang Lake into three study areas. Except for the number of anglers, there were no significant differences among the three study areas in the kinds of avian predators, the water depth around study areas measured for possible territorial predatory mammals' passing over, and the values of Relative Importance Percentage of occupying plants. The results showed that waterfowls bred in Namyang Lake preferred the areas with few anglers for the nests. From this study, we recommend that leisure activities including fishing should be prohibited or restricted during the breeding periods of waterfowls for the stable breeding success and that further systematic researches and managements for the species are necessary.

Development of Wheat-Leymus Addition Line with Salt Tolerance throgh Wide-hybridization (국내 자생 갯그령(Leymus mollis)의 환경 적응성 강화 밀 자원 소재 개발을 위한 이용 가치)

  • Seong-Wook Kang;Ji-Yoon Han;Seong-Woo Cho
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2022.09a
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    • pp.37-37
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    • 2022
  • 밀은 세계 3대 작물로 국내 1인당 소비량은 지속적으로 증가하고 있다. 하지만 국내 밀의 유전적 배경 확대와 기후변화 신속 대응을 위한 국내 밀 유전자 풀의 확장은 밀의 질적 향상을 위해 매우 중요한 목표이다. 국내 자생 갯그령(Leymus mollis)은 해안가에서 번식하는 영년생 식물로 뿌리줄기를 이용한 왕성한 번식력을 가지고 있다. 또한, 해안가의 뜨겁고 염에 대한 적응성과 저항성을 가지고 있다. 이러한 특성은 밀 유전자 풀의 확장에 매우 유용할 것이다. 국내 밀 재배지 한계 극복을 위한 간척지 재배가 가능한 내염성 강화 밀 자원 개발을 위하여 모본인 보통 밀(Triticum aestivum L., Chinese Spring)과 부본인 갯그령을 원연교배하였다. 갯그령과 보통 밀의 원연 교배를 통한 종자 형성은 매우 어려우나 불가능한 것은 아니며, 최종적으로 10개의 교배 종자를 얻어 F1 식물체로 생장하는 과정에서 5 식물체는 고사하였고, 나머지 5 식물체는 영년생 특성인 뿌리줄기에 의해 새로운 줄기가 출현하는 것을 확인하였다. 또한, 갯그령의 DNA를 이용한 genomic in situ hybridization 방법으로 F1 식물체에서 갯그령의 염색체가 밀의 유전적 배경에 이입된 것을 확인하였다. F2 식물체는 모본인 보통 밀보다 긴 수장과 간장을 나타내고 이삭 수는 많았지만, 출수기는 보통 밀보다 3주 이상 늦어지는 것을 확인하였다. 내염성 평가를 위하여 F2 종자를 2% 소금물에서 발아시켜 생육이 좋은 식물체를 선발하여 50 cm 투명 아크릴 원통에 이식하고 2% 소금물을 지속적으로 관개하였다. 내염성 강화 F2 식물체는 염에 감수성을 보인 식물체에 비하여 상대적으로 긴 이삭과 종자 형성을 보였으며, 감수성 식물체는 종자 형성이 이루어지지 않았다. 또한, 내염성 강화 F2 식물체는 감수성 식물체에 비하여 좋은 뿌리의 신장과 천근성을 보였다. 이러한 갯그령의 식물학적 특성이 이입된 계통은 기후변화 대응, 환경 적응성 강화, 및 근권 강화에 좋은 작물 소재로 이용할 수 있다고 생각한다.

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A Study on the Breeding Density and Diet of Magpie Pica pica in Jeju Island1a (제주도에 서식하는 까치 Pica pica의 번식 밀도 및 식이물에 관한 연구)

  • Park, Joo-Yeon;Kim, Byoung-Soo;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
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    • v.22 no.6
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    • pp.648-657
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    • 2008
  • This research was conducted to investigate the breeding density and seasonal food items of the magpies in Jeju Island and the near-manned islets. The examination of nest distribution to determine breeding density was performed during breeding season from February 2006 to April 2008, and that of food items from May 2006 to February 2008. A total of 2,113 nests were found across Jeju Island, the average density was $1.33\;nest/km^2$, and the magpies were distributed up to 600 meters above the sea level. The nest density was the highest in the central areas of Jeju Island, with 688 nests at $3.61\;nest/km^2$, while that in the eastern areas was the lowest, with 214 nests at $0.66\;nest/km^2$. In terms of the number of nests depending on the height above the sea level, 1,172 nests, which was equivalent to the density of $1.85\;nest/km^2$, was observed below 100m and highest among the intervals of height, but 16 nests found at 500-600m were the lowest, corresponding to $0.20\;nest/km^2$. The number of nests found in the manned islets near Jeju Island was eight in Biyang-do with the density of $15.38\;nest/km^2$, nine in U-do with $1.49\;nest/km^2$, and one in Gapa-do with $1.15\;nest/km^2$, whereas none of nests were observed in Mara-do. The contents of stomach consisted of 17 types of prey sources including countless bones, eggshells, plants, and seed, most of which were the individuals of the order Coleoptera. In spring and summer, the foraging frequency for invertebrate animals such as insects was high, but less than 30% in winter. In contrast, the magpies preyed upon plants and seeds at the frequency of 10% and 30%, respectively, in spring, while the foraging frequencies for both of them were 100% in winter and higher than any of other seasons. Eggshells and bones of birds were also detected infrequently. If the density of the magpies, which may play role as the upper predator within the ecosystem, increases, it would be expected to affect directly the reduction of the number of the species and population of endemic animals such as small birds and reptiles, etc. Therefore, it is considered that long-term monitoring for the density of the magpies and precaution is prerequisite to minimize adverse effects on ecosystem.

요각류 Calanus helgolandicus의 번식력에 미치는 단일, 혼합 먹이, 알 포식의 영향

  • ;Serge Poulet
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.359-360
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    • 2000
  • 해양 생태계에서 규조류는 요각류의 생산력에 필요한 중요한 먹이인 것으로 인식되고 있다. 그러나, 많은 실험실 연구에서 규조류가 요각류의 번식력을 억제할 수 있음을 보여주고 있다 (Ban et al., 1997; Poulet et at., 1994, 1995; Chaudron et al., 1996). 요각류 성체 암컷이 규조류를 섭식할 경우 요각류의 알 생산력이나 알 부화율이 낮아질 수 있으며, 이러한 저해 작용은 규조류가 아닌 다른 먹이 (와편모조류)로 대체하였을 경우, 정상적으로 회복될 수 있으며, 이러한 저해 작용은 먹이로 제공된 규조류의 밀도가 높을수록 더 강하게 나타나고 있었다. 이러한 증거들로 인하여 실제 해양에서 요각류의 번식력과 규조류 사이의 연결성에 대하여 의문이 제기되고 있다. (중략)

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Breeding Population and Habitat of Black-tailed Gulls (Larus crassirostris) on Nando Island, Natural Monument (천연기념물 난도에서 번식하는 괭이갈매기 개체군 및 서식 환경)

  • Kim, Miran;Kwon, Young-Soo;Nam, Ki-baek;Lee, Ho;Myeong, Hyeon-Ho;Noh, Hyung Soo
    • Korean Journal of Environmental Biology
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    • v.35 no.2
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    • pp.134-142
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    • 2017
  • Nando Island is reported as one of the biggest breeding colonies of seabirds in South Korea, and is protected as a Natural Monument. This study was conducted between July to November 2015, to investigate the breeding population of Black-tailed gulls and their habitat on Nando Island. We estimated the breeding population of Black-tailed gulls (Larus crassirostris) using nest density. The mean nest density of Black-tailed gulls was $0.51\;per\;1m^2$ ($0.51m^{-2}$), and the breeding population was approximately 26,760 individuals. The dominant vegetation was Echinochloa crusgalli and Agropyron tsukushiense var. transiens, which served as shelter and nest sites to Black-tailed gulls. The diet of Black-tailed gulls was mainly the fish, Japanese Anchovy Engraulis japonicas (48%). Other species which were found to breed on Nando Island were Streaked Sheawater (Calonectris leucomelas), Temminck's Cormorant (Phalacrocorax capillatus), and Swinhoe's storm petrels(Oceanodroma monorhis).

Effects of Habitat Environment on Bird Community in Forest (산림지역에서 서식지 환경이 조류군집에 미치는 영향)

  • Kim, Jung-Soo;Shin, Ju-Ryul;Lee, Hwa-Su;Koo, Tae-Hoe
    • Journal of Environmental Policy
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    • v.7 no.3
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    • pp.141-160
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    • 2008
  • The effects of disturbance on bird community were studied in Ssanggok Valley and Beopju Temple area, Songni Mt. National Park in $2006{\sim}2008$. We divided three sites by habitat condition such as traffic road(strong disturbance), trail(medium) and control(weak) site. During breeding and non-breeding seasons(n=12), number of species, number of individuals, species diversity and density did not differ among three sites, but in breeding season(n=9), number of species(Kruskal Wallis, $x^2$=10.32, p=0.006), number of individuals(Kruskal Wallis, $x^2$=7.118, p=0.028) and species diversity of birds(Kruskal Wallis, $x^2$=9.847, p=0.007) were significantly higher in trail site with medium disturbance than in other sites. In breeding season, nesting and foraging guild rate were not different among three sites. In guild analysis, hole was the highest nesting guild and canopy was the highest foraging guild in three sites.

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Differences in Breeding Bird Communities by Post-fire Restoration Methods (산불 후 복원방법의 차이가 번식기 조류 군집에 미치는 영향)

  • Kim, Jin-Yong;Lee, Eun-Jae;Choi, Chang-Yong;Lee, Woo-Shin;Lim, Joo-Hoon
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.508-515
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    • 2015
  • Post-fire restoration can affect breeding bird communities and species compositions over a long-term period by determining pot-fire succession, and a long-term monitoring is therefore required to understand its impacts on forest birds. This study aimed to document the effects of post-fire restoration methods on breeding bird communities in three areas: unburned and two burned (nonintervention and intervention with clear-cut logging and planting) stands 13 years after the stand-replacing Samcheok forest fire at Mt. Geombong in Samcheok, South Korea. According to 108 point counts during the breeding season from April to June 2013, we found that the number of individuals, observed bird species, and species diversity index in intervention stands with clear-cut logging and planting were lower than that in nonintervention and unburned control stands. Foraging and nesting guild analysis also showed a lower abundance of foliage searchers, timber drillers, primary cavity nesters and secondary cavity nesters in intervention stands than in the other stands, while no significant difference was detected between the nonintervention and unburned stands. These results imply that an interventional restoration method may deter the recovery of avian breeding communities after forest fires, and also suggest that non-interventional restoration methods may be an effective way to benefit the species diversity and density of breeding bird communities.

Changes in Breeding Bird Community Caused by Thinning in Deciduous Forest (활엽수림(闊葉樹林)에서 간벌(間伐)에 의(依)한 번식기(繁殖期) 조류(鳥類) 군집(群集)의 변화(變化))

  • Rhim, Shin-Jae;Lee, Woo-Shin
    • Journal of Korean Society of Forest Science
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    • v.90 no.1
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    • pp.36-42
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    • 2001
  • Changes in breeding bird community and forest structure by thinning were investigated from April 1997 to August 1998 in 10ha ($400{\times}250m$) of temperate mixed hardwood forest in Mt. Gariwang which is located in National Forest, Pyoungchang, Kangwon Province, Korea. Bird community was surveyed by the territory mapping method and forest structure was done by analyzing the vertical structure of foliage, distribution of diameter at breast height (DBH) of trees and tree species composition. After the thinning, tree density, number of tree species and basal area were decreased from 195ea/ha, 18 species and 6.69 $m^2/ha$ into 100ea/ha, 13 species and 3.04 $m^2/ha$, respectively. Foliage coverages in upper and mid layer were decreased, but coverage in low layer was increased. Large trees (Over 40cm of DBH) were decreased. Number of breeding bird species and pairs were decreased from 14 species and 23 pairs into 8 species and 12 pairs after the thinning. Number of breeding pairs of Yellow-breasted bunting Emberiza elegans incresed. There were decrease in number of species in hole & bush-nesting and canopy & bush-foraging guild. The results suggested that the thinning affect the species composition of breeding bird community and the forest structure. Changes of habitat structure might influence in breeding bird's density, species diversity and habitat using pattern of breeding bird community.

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