• 제목/요약/키워드: feeding site types

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유부도 일대에 서식하는 검은머리물떼새 (Haematopus ostralegus osculans)의 번식기 섭식지 유형에 따른 섭식행동과 먹이원 (Foraging Behavior and Preys in Relation to Feeding Site Types of the Eurasian Oystercatcher (Haematopus ostralegus osculans) during the Breeding Season in Yubu Island, Korea)

  • 이상연;최유성;주성배;정길상;유영한
    • 생태와환경
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    • 제51권2호
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    • pp.184-191
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    • 2018
  • 섭금류인 검은머리물떼새(Haematopus ostralegus osculans)는 주로 조수 경계부를 섭식지로 이용하는데, 번식기에는 간조시 드러난 갯벌에서 섭식하는 개체들이 일부 관찰된다. 드러난 갯벌에서 섭식하는 경우 조수 경계부에 비해 걸음수가 더 많고, 먹이탐색을 위해 중복탐침과 찔러넣기 행동의 비율이 더 높았지만, 섭식성공률은 현저히 낮았다. 또한, 주요 먹이원은 드러난 갯벌에서는 갯지렁이류였지만, 조수 경계부에서는 복족류(서해비단고둥)와 이매패류로 섭식지 유형간 뚜렷한 차이가 있었다. 번식기에 국한하여 드러난 갯벌을 섭식지로 이용하는 현상은 본래 선호하는 섭식지에 비해 효율이 떨어지더라도 번식 성공을 위해 번식지와 가까운 지역을 섭식지로 이용하는 것으로 판단된다. 본 연구는 번식이라는 생활사 변화에 맞춰 검은머리물떼새가 섭식행동과 먹이원을 달리함으로써 환경 변화에 대한 적응이 가능하다는 것을 제안한다.

Characterizing Ecological Exergy as an Ecosystem Indicator in Streams Using a Self-Organizing Map

  • Bae, Mi-Jung;Park, Young-Seuk
    • 환경생물
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    • 제26권3호
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    • pp.203-213
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    • 2008
  • Benthic macro invertebrate communities were collected at six different sampling sites in the Musucheon stream in Korea from July 2006 to July 2007, and ecological exergy values were calculated based on five different functional feeding groups (collector-gatherer, collector-filterer, predator, scrapper, and shredder) of benthic macro invertebrates. Each sampling site was categorized to three stream types (perennial, intermittent and drought) based on the water flow condition. Exergy values were low at all study sites right after a heavy rain and relatively higher in the perennial stream type than in the intermittent or the drought stream type. Self-Organizing Map (SOM), unsupervised artificial neural network, was implemented to pattern spatial and temporal dynamics of ecological exergy of the study sites. SOM classified samples into four clusters. The classification reflected the effects of floods and droughts on benthic macroinvertebrate communities, and was mainly related with the stream types of the sampling sites. Exergy values of each functional feeding group also responded differently according to the different stream types. Finally, the results showed that exergy is an effective ecological indicator, and patterning changes of exergy using SOM is an effective way to evaluate target ecosystems.

사업체 단체급식소의 유형에 따른 급식운영실태 평가 (Assessment of foodservice management practices in the employee feeding operations according to type of workers)

  • 곽동경;장미라
    • 대한영양사협회학술지
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    • 제3권1호
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    • pp.63-73
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    • 1997
  • This study was conducted to evaluate the industry foodservice management practices and to suggest guidelines for the effective foodservice management. The survey for the analysis was conducted through the questionnaires to dietitians. They were divided into two groups : the site color worker and the blue color worker. The questionnaires were received for a response rate of 73.2%. Statistical data analysis was completed using the SAS programs for descriptive analysis, $x^2$ test, T-test, F-test, and Fisher's LSD. The results of the study can be summarized as follows : 1) The level of education of dietitians and food cost in the employee feeding operations for the blue color worker was lower than the employee feeding operations for the white color worker. 2) The labor productivity indices were not significantly different according to types of workers. But in the employee feeding operations for the blue color worker, full-time foodservice employees worked more than 10.7 hour per week than their counterpart. This indicates the full-time foodservice employees in the employee feeding operations for the blue color worker performed more loaded work compared to the employee feeding operations for the white color worker. 3) Equipped rate of facilities in the employee feeding operations for the blue color worker was low especially in the food preparation and cooking processes.

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Foraging Habitat Preferences of Herons and Egrets

  • Choi, Yu-Seong;Kwon, In-Ki;Yoo, Jeong-Chil
    • Journal of Ecology and Environment
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    • 제30권3호
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    • pp.237-244
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    • 2007
  • We investigated the foraging habitat preferences of herons and egrets in an agricultural area in Asan city, Chungcheongnam-do, Korea. In the study area, rice fields were the most abundant habitat type (86.8%) and total suitable feeding habitat was greater in the northern area (59.0%) than the southern area (22.5%) of the colony. Most feeding herons and egrets were located in the northern area of the colony. The number of feeding individuals in a given area was related to the available feeding area (Pearson correlation, r=0.773, p<0.001 for field habitats; r=0.901, p<0.001 for freshwater habitats). Feeding habitat preferences differed among species. Grey herons (Ardea cinerea), great egrets (Egretta alba), and black-crowned night herons (Nycticorax nycticorax) used reservoirs and ditches. However, intermediate egrets (E. intermedia) and cattle egrets (Bubulcus ibis) were dependent on rice fields. The little egret (E. garzetta) was a habitat generalist using all types of habitats. The two largest species, grey herons and great egrets, fed at deeper site than little egrets and foraged in deeper sites in reservoirs than in ditches (${\chi}^2-test,\;{\chi}^2{_3}=26.6$ and p<0.001 for grey herons, ${\chi}^2{_3}=17.5$ and p<0.001 for great egrets). All species displayed seasonal changes in feeding habitat use and these changes were related with changes in availability of feeding habitats.

도심하천과 자연하천의 식생형에 따른 조류 서식지 유형분석 (Classification of Avian Habitats Based on Vegetation Types in Urban and Natural Streams)

  • 표재훈;유영한
    • 한국습지학회지
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    • 제13권1호
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    • pp.67-77
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    • 2011
  • 우리나라 중부지역에 입지하는 3개 하천(안양천, 갑천, 섬강)을 대상으로 식생형에 따른 조류의 서식 유형을 파악하였다. 식생 유형은 교목형, 관목형, 장경-습생초지형, 단경-건생초지형, 기타 경작지형 등 5가지 유형이었다. 식생형과 출현 조류는 상관성이 높았는데, 교목형에서는 멧비둘기(Streptopelia orientalis) 및 직박구리(Hypsipetes amaurotis) 등의 종이, 관목형에서는 붉은머리오목눈이(Paradoxornis webbiana), 딱새(Phoenicurus auroreus) 등이, 장경 및 습생초지에서는 덤불해오라기(Ixobrychus sinensis), 개개비(Acrocephalus arundinaceus)등이, 단경초지에서는 꿩(Phasianus colchicus), 황조롱이(Falco tinnunculus) 등의 종이, 경작지에서는 중대백로(Egretta alba modesta), 흰뺨검둥오리(Anas poecilorhyncha) 및 밭종다리(Anthus spinoletta) 등의 종이 각각 번식 및 채식지로 이용하였다. 현존식생 및 입지유형에 따라서 조류의 종별 분포유형이 뚜렷이 구분되었다.

양식어류의 자동먹이공급장치 개발 연구-I (A study on the development of auto-feeding system for the cultured fish-I)

  • 양용수;배재현;배봉성;안희춘;김인옥;이배익;정용길
    • 수산해양기술연구
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    • 제42권4호
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    • pp.234-239
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    • 2006
  • This paper introduces an auto-feeding system to exactly control the feeding time and the amount to cultured fishes in aquaculture industrial field. To reduce expensive costs or labors in this field, it was designed by the concept of controlling feed quantity exactly on the basis of fish's feeding behavior pattern in water tank. A feed control method of this system was developed for controlling feed amount by rotor capacity and motor rotated number. Moreover, a scattering section was selected by rotate way of propeller wing to scatter dried feed to designated site, and then, the diameter of its wing was 250mm and maximum scattering distance was 7.6m for 600rpm. Furthermore, the scattering ways were embodied 2 types such as a simplified way and a multistage shift way looks like a manual scattering. As a results, the multistage shift way is more effective to discharge the dried feed widely than the simple way in the water tank.

Artificial Habitat Creation of Luciola lateralis (Coleoptera: Lamphyridae) and Research of Breeding Technique for Festival at Hwadamsup, Korea

  • Kang, Seung-Ho;Jeon, Mi-Kyung;Kwon, Soon-Jik;Na, Seok-Jong;Kim, Kyung-Ho;Jeong, Jong-Chul
    • Journal of Forest and Environmental Science
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    • 제34권4호
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    • pp.275-283
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    • 2018
  • This study created the running water (Bandibooliwon) and lentic water (Sooryunwon) artificial habitats of Luciola lateralis in Hwadamsup, Gwangju-si, Gyunggi-do from April 2014 to February 2016. Through various habitat types, metapopulation was formed, and more sound population was induced to be maintained via interactions between habitats. We investigated coenosite at the habitat creation-target site, and 20 species in the lentic water site and 38 species in running water site were found. After releasing L. lateralis, we checked the status of settlement of L. lateralis larvae through traps and macroscopy, controlled the flow velocity of the habitats in line with the life cycle of L. lateralis (hatching, larva period, landing, pupation, copulation, and oviposition), and shaped gentle slope at water side, and planted moss. We artificially supplied melanian snails (Semisulcospira sp.), the food source, in the running water site and induced stable feeding. Also, We created artificial insectary, bred larvae stably in winter, and secured firefly population for a festival. Through night time observation, the time most suitable for a festival was confirmed to be from 20:30 to 22:00.

Changes in Benthic Macroinvertebrate Communities in Response to Natural Disturbances in a Stream

  • Bae, Mi-Jung;Park, Young-Seuk
    • Journal of Ecology and Environment
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    • 제32권3호
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    • pp.197-206
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    • 2009
  • Benthic macroinvertebrate communities were collected from six different sites in the Dobong Stream in Seoul, Korea to investigate spatial and temporal changes in benthic macroinvertebrate communities in response to natural disturbances such as floods and droughts. We collected samples monthly or semimonthly with a Surber net ($30cm{\times}30cm$), and measured environmental factors, including stream temperature, discharge, width, conductivity, dissolved oxygen and pH at each sampling site. Benthic macro invertebrates were strongly affected by floods as well as droughts. In addition, benthic macroinvertebrate communities displayed different responses to the onset of the rainy season in summer 2006 and 2007, apparently due to differences in the intensity and amount of precipitation. Chironomids were particularly sensitive to heavy rain. Floods and droughts also affected the proportions of functional feeding groups during the survey period: the proportion of scrapers was high right after heavy rains, while the proportion of predators tended to increase in intermittent-type streams as the riffle zone decreased. Finally, although species richness and abundance were strongly influenced by heavy rain, they recovered to background levels for within one month, and varied consistently among stream types, indicating habitat stability.

사방공작물 시공이 저서성 대형무척추동물 군집에 미치는 영향 (Effect of Erosion Control Works on Benthic Macroinvertebrate Communities)

  • 이익수;정유경;이헌호
    • 한국산림과학회지
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    • 제101권4호
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    • pp.686-694
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    • 2012
  • 본 연구는 산지 황폐계류에 시공한 사방공작물이 저서성 대형무척추동물상에 미치는 영향을 밝히기 위하여 수행하였다. 2007년 4월부터 2008년 10월까지 총 6회에 걸쳐 사방공작물이 설치되지 않은 계곡 상류지역의 대조지점(Site 1)과 사방공작물이 시공된 2개의 지점(Site 2, Site 3)을 대상으로 저서성 대형무척추동물상의 변화와 생물학적 수질 변화를 조사하였다. 저서성 대형무척추동물상은 조사결과 4문 6강 13목 24과 27종 6,922개체가 조사되었으며, 조사지점 평균값으로 볼 때 단각목의 보통옆새우가 우점종으로 나타났다. 다양도지수는 Site 2의 4차 조사에서 1.47로 가장 높았으며, Site 2의 6차 조사에서 0.24로 가장 낮게 나타났다. 균등도지수는 Site 2의 4차 조사에서 0.823으로 가장 높게 나타났고, Site 1의 5차 조사에서 0.194로 가장 낮게 나타났다. 풍부도지수는 Site 1의 1차 조사에서 2.794로 가장 높게 나타났고 Site 2의 6차 조사에서 0.291로 가장 낮게 나타났다. 저서성 대형무척추동물 생태점수 (ESB)는 조사기간동안 낮아지는 경향을 보였다. 섭식기능군은 SH(Sherdder)가 조사기간동안 가장 많은 개체수로 조사되었으며, EPT분류군 개체수가 낮아지는 경향을 보였다.

Evaluation of Environmental Factors to Determine the Distribution of Functional Feeding Groups of Benthic Macroinvertebrates Using an Artificial Neural Network

  • Park, Young-Seuk;Lek, Sovan;Chon, Tae-Soo;Verdonschot, Piet F.M.
    • Journal of Ecology and Environment
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    • 제31권3호
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    • pp.233-241
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    • 2008
  • Functional feeding groups (FFGs) of benthic macroinvertebrates are guilds of invertebrate taxa that obtain food in similar ways, regardless of their taxonomic affinities. They can represent a heterogeneous assemblage of benthic fauna and may indicate disturbances of their habitats. The proportion of different groups can change in response to disturbances that affect the food base of the system, thereby offering a means of assessing disruption of ecosystem functioning. In this study, we used benthic macroinvertebrate communities collected at 650 sites of 23 different water types in the province of Overijssel, The Netherlands. Physical and chemical environmental factors were measured at each sampling site. Each taxon was assigned to its corresponding FFG based on its food resources. A multilayer perceptron (MLP) using a backpropagation algorithm, a supervised artificial neural network, was applied to evaluate the influence of environmental variables to the FFGs of benthic macroinvertebrates through a sensitivity analysis. In the evaluation of input variables, the sensitivity analysis with partial derivatives demonstrates the relative importance of influential environmental variables on the FFG, showing that different variables influence the FFG in various ways. Collector-filterers and shredders were mainly influenced by $Ca^{2+}$ and width of the streams, and scrapers were influenced mostly with $Ca^{2+}$ and depth, and predators were by depth and pH. $Ca^{2+}$ and depth displayed relatively high influence on all four FFGs, while some variables such as pH, %gravel, %silt, and %bank affected specific groups. This approach can help to characterize community structure and to ecologically assess target ecosystems.