• 한국작물학회지
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• 제28권3호
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• pp.319-322
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• 1983

벼 이앙후에 발생되는 잡초를 조사하여 벼와의 경쟁적 영향을 해석함에 있어 가장 적은 노력으로 전체잡초발생상태를 대표할 수 있는 최소표본크기(minium quadrat size)와 최소표본회수(minimun quadrat number)를 초종일표본변적(species-area) 및 초종일표본회수(species-quadart number) 관계식에 의해 조사하였다. 1. 초종일표본면적, 또는 초종일표본회수 관계식에서 다같이 표본면적, 또는 표본회수가 증가하게 됨에 따라 얻어지는 초종증가는 처음에는 급속도로 증가하고, 서서히 증가속도가 완만해지며, 어느 한계점을 지나면 더 이상의 초종증가는 없이 평형상태를 유지하는 특징적인 곡선을 보였다. 2. 표본추출면적, 또는 표본 추출회수를 10% 증가시킴에 따라 얻어지는 초종 증가율이 10%되는 관계를 고려한 최소표본추출 회수는 3회였다.

• 한국응용곤충학회지
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• 제49권4호
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• pp.313-324
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• 2010

논의 생물다양성에 관한 관심이 증가하면서 논 먹이망의 중요한 부분을 차지하고 있는 수서성 대형무척추동물을 정량적으로 평가하기 위한 효율적인 방법이 요구된다. 이를 위해, 강원도 춘천시와 충청남도 홍성군에 위치한 논에서 채집망과 방형구, 피이프형 채집기(core)로 얻어진 자료를 비교하여 적절한 채집기를 알아보았다. 채집망은 틀이 사각형이고, 바닥이 평평하기 때문에, 채집망의 조사 면적은 토양을 훑은 길이와 망의 넓이를 곱하여 측정되었다. 모든 채집물은 두 벼줄 사이에서 채집되었다. 대형무척추동물은 춘천과 홍성에서 24, 28분류군이 채집되었다. 춘천에서 분류군수는 세 가지 채집기에서 유사했지만(17-18분류군), 추정밀도는 그렇지 않았다(채집망, $1317/m^2$; 방형구, $1368/m^2$ core, $1810/m^2$). 홍성에서는 채집망에서 분류군 수가 가장 컸었지만(채집망 25분류군; 방형구, 21분류군 core, 16분류군), 추정밀도는 core에서 가장 높았다(채집망, $1586/m^2$; 방형구; $2595/m^2$; core $3704/m^2$). 각 채집기의 효율은 분류군에 따라 달랐는데, 채집망에는 주로 수서곤충류가 많았던 것에 비해 방형구에는 빈모류나 깔따구과 등 토양 속에 서식하는 종류에 대한 효율이 높았다. 논에 서식하는 수서곤충에 대한 정량자료와 희귀분류군에 대한 정성자료를 통시에 얻고자 하는 경우에는 채집망을 이용하여 논 가장자리와 논 내부에서 각 6회 정량채집하고, 논둑 근처와 논 가운데에서 정성채집을 수행되는 것이 시간 및 노동력 측면에서 가장 경제적 이라고 생각된다.

• 한국패류학회지
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• 제30권1호
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• pp.95-99
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• 2014

In the present study, we surveyed the molluscan fauna in a lagoon located near Seong-san harbor on the east coast of Jeju Island in July 2012. For the survey, a $25{\times}25cm$ quadrat was deployed over 3 randomly selected sites in the intertidal area of the lagoon. Sediment from the surface to a depth of 25 cm in the quadrat was removed and sieved using a 1 mm mesh sieve. All molluscan fauna retained on the sieve was identified to the species level. From the survey, 25 species of mollusca belonging to 2 orders and 16 families were identified. Species richness, in terms of total number of species, was found to be the highest at sampling site 1, where the substrate was composed of coarse sand and some rocks, while it was lowest at sampling site 3, composed of compact fine sand. Regardless of the type of substrate at the sampling sites, the mud-creeping snail Batillaria cumingii (Crosse, 1862) occurred at a high density, ranging from $324-468ind./m^2$. The luciniid bivalve Pillucina pisidium also occurred at a high density at sampling site 1, at $336ind./m^2$, while the density of this species was only $4ind./m^2$ at sampling site 3. The Manila clam Ruditapes philippinarum could be found at all 3 sampling sites with very low density ranging from $16-48ind./m^2$. The density and species richness of molluscs observed in this study was lower compared to the previously reported molluscan fauna in Jeju Island, suggesting that further investigation needs to be carried out to conserve the unique marine lagoon ecosystem in Jeju Island.

• 한국수산과학회지
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• 제57권3호
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• pp.278-291
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• 2024

This study performed three research methods (destructive, non-destructive, and panoramic image analysis) to determine the most useful for identifying seaweed habitat characteristics. Panoramic images are suitable for understanding the overall seaweed distribution. The composition of the main dominant seaweed species showed a significant difference between the destructive and non-destructive methods using Quadrat. The destructive method showed Rhodophyta dominance, whereas the non-destructive was showed Phaeophyta as dominant. Destructive methods are disadvantageous because they destroy natural communities in sea areas where bleaching is severe. Non-destructive methods are disadvantageous because of the difficulty in analyzing small species. Performing 10 surveys using a non-destructive method was found to explain up to 80% of the species identified by the destructive method. However, considering the difficulty of field investigation, repeating the investigation with non-destructive methods at least 6-7 times is necessary to ensure that more than 60% of the destructive methods can be interpreted. To understand the distribution of oceanic marine algae, performing both destructive and non-destructive surveys are necessary, as each has its own merits and demerits.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.183-190
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• 2019

Background: In the Philippines, the practice of planting mangroves over seagrass has been a practice done to promote coastline protection from damages done by storms. Despite the added protection to the coastline, the addition of an artificial ecosystem gradually inflicts damage to the ecosystem already established. In this study, seagrass communities that had no history of mangrove planting were compared with those that had mangrove planting. The percent substrate cover of seagrass in the sampling areas was determined, and the macroinvertebrates present in the sampling areas were also observed. The study was conducted based on reports of mangrove planting activity that disrupted seagrass functions on Santa Fe, Bantayan Island, Cebu. Transect-quadrat method sampling was done to assess the chosen sites. Results: Six species of seagrass was found on the site without mangrove planting which was barangay Ocoy (Cymodocea sp., Thalassia sp., Halodule sp., Enhalus sp., Halophila sp., and Syringodium sp.) and had a higher percent cover, while only four were found on the site with mangrove planting (barangay Marikaban). It was also found that barangay Marikaban had a lesser Shannon-Wiener and Simpson's index compared to barangay Ocoy. Jaccard's index of similarity between the two sites was low. Conclusion: With the results of the assessment, we recommend proper monitoring of future mangrove planting activities and that these activities should not disrupt another ecosystem as all ecosystems are important.

• ALGAE
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• 제23권4호
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• pp.289-294
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• 2008

To estimate seaweed biomass or standing crop, a nondestructive sampling can be beneficial because of not much destroying living plants and saving time in field works. We suggest a methodological procedure to estimate seaweed biomass per unit area in marine benthic habitats by using species-specific regression equations. Percent cover data are required from the field samplings for most species to convert them to weight data. However, for tall macroalgae such as kelps we need density data and their size (e.g., size class for subtidal kelps) of individuals. We propose that the field sampling should be done with 5 replicates of 50 cm x 50 cm quadrat at three zones of intertidals (upper, middle, lower) and three depth points (1, 5, 10 m) in subtidals. To obtain a reliable regression equation for a species, a substantial number of replicate is necessary from destructive samplings. The regression equation of a species can be further specified by different locality and different season, especially for the species with variable morphology temporally and spatially. Example estimation carried out in Onpyung, Jeju Island, Korea is provided to compare estimated values with real weight data.

• 환경생물
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• 제35권4호
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• pp.640-647
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• 2017

생물다양성 측면에서 논 생태계의 중요성이 대두되면서 수서생물을 효율적으로 채집하는 방법이 요구되고 있다. 본 연구는 논 생태계 내에서 수서생물을 객관적이고 정량적으로 쉽게 채집하기 위해 두 가지 유인제(어분, 캐미라이트)를 활용한 수중트랩을 고안하였다. 고안된 트랩으로 채집된 수서생물의 유인제 선호도는 일반화선형혼합모형을 통해 분석되었다. 또한 선행연구의 데이터를 활용하여 방형구와 수중트랩으로 채집된 수서 무척추동물의 군집 조성을 비계량형다차원척도법을 통해 비교 분석하였다. 그 결과, 수중트랩에 의해 채집된 65분류군의 수서생물 중 18분류군이 유인제에 의해 채집효율이 달라지는 것을 확인하였다. 18분류군 중왕우렁이, 수정또아리물달팽이, 애기물달팽이, 돌거머리, 패충류, 풍년새우, 꼬마줄물방개, 애기물방개, 깔따구류, 참개구리, 미꾸리류 등 12분류군은 어분을 선호하였고, 아시아실잠자리, 실잠자리류, 깃동잠자리, 방물벌레, 검정배물벌레, 애물땡땡이 등 6종은 캐미라이트를 선호하였다. 또한 수중트랩은 방형구법에 비해 생물다양성의 측정도구로서의 활용도는 낮지만 특정 분류군의 선택적인 채집에는 효과적이었다. 본 연구에서 간단하고 정량적인 방법으로 수서생물을 채집할 수 있도록 고안된 트랩은 장기적이고 광범위한 논 수서생물 생태 조사에 유용하게 활용될 수 있을 것으로 판단된다.

• 환경생물
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• 제36권2호
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• pp.99-106
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• 2018

기존에 주로 논 수서생물의 채집을 위해 사용된 방형구법과 뜰채법은 높은 노동력을 요구했기 때문에 광범위한 지역을 대상으로 한 모니터링이 어려웠다. 이 연구는 논 수서생물을 보다 신속하게 채집할 수 있는 수중트랩을 사용하여 지역 및 시기별 논 수서생물의 군집 조성을 확인하였다. 수중트랩은 논을 대표하는 수서생물 중 환경 변화를 지표하거나 수조류의 먹이가 되는 이동성이 높은 종이 포함된 분류군을 채집하는 데 유용했다. 사과우렁이과 (Ampullariidae), 미꾸라지과 (Cobitidae), 물벌레과 (Corixidae), 물방개과 (Dytiscidae), 물땡땡이과 (Hydrophilidae), 물달팽이과 (Lymnaeidae) 등 15개 분류군은 논 수서생물 군집 조성을 결정했다. 주요 분류군 중 환경 교란에 강한 깔다구과 만이 논 수서생물 군집의 시기 변화를 대표했다. 인위적인 영향에 민감한 사과우렁이과, 물땡땡이과 그리고 물방개과는 지역별로 분포가 상이했다.

• ALGAE
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• 제23권4호
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• pp.327-334
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• 2008

Seaweed biomass was estimated using a nondestructive sampling method in the rocky intertidal and subtidal zone in Daejin on the mid-east coast of Korea from August 2006 to April 2008. Seasonal sampling were done at the depth of 0, 1, 5, 10 m using 50 x 50 cm quadrat. A total of 95 species, including 11 chlorophytes, 26 phaeophytes, 57 rhodophytes and one sea grass were identified. Mean biomass was comprised of 1,292 g wet wt m$^{-2}$ and the biomass values varied seasonally from 904 g to 1,945 g. Dominant species in biomass were Sargassum spp. (S. horneri, S. yezoense), Corallina pilulifera, Phyllospadix japonica, Symphyocladia latiuscula, Hizikia fusiformis, Codium arabicum and Chondrus ocellatus at Daejin. The vertical distribution of algae were characterized by Corallina pilulifera, Symphyocladia latiuscula, Sargassum spp. (S. confusum, S. yezoense), Hizikia fusiformis and Grateloupia elliptica at intertidal zone, Sargassum spp. (S. fulvellum, S. horneri, S. yezoense), Phyllospadix japonica, Codium arabicum, Undaria pinnatifida and Corallina pilulifera at 1 m depth, Sargassum spp. (S. horneri, S. micracanthum, S. yezoense), Phyllospadix japonica, Grateloupia elliptica, Gelidium amansii and Codium arabicum at 5 m depth and Phyllospadix japonica, Codium arabicum, Sargassum spp. (S. horneri, S. micracanthum, S. yezoense) and Undaria pinnatifida at 10 m depth.

• ALGAE
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• 제23권4호
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• pp.311-316
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• 2008

The seasonal variation of marine algal biomass and community were studied with nondestructive sampling and quadrat method during May 2006 to April 2008 in the intertidal and subtidal zone at Yokjido. As result, total 120 species, 13 Chlorophyta, 34 Phaeophyta, 71 Rhodophyta and 2 Spermatophyta were identified in this study. The major species which contributed significantly to the total biomass were Ulva pertusa, Undaria pinnatifida, Ecklonia stolonifera, Sargassum horneri, S. serratifolium, Gelidium amansii and Prionitis cornea. The mean biomass was 235.5 g wet wt m$^{-2}$ in intertidal, 1,038.9 g wet wt m$^{-2}$ in 1 m, 1,013.1 g wet wt m$^{-2}$ in 5 m, and 19.7 g wet wt m$^{-2}$ in 10 m depths of mean sea level. Seasonal biomass change in intertidal zone, the peak season was in spring, while the lowest was in autumn. The vertical distribution of marine vegetation was characterized by Ulva pertusa - Gelidium divaricatum - Gloiopeltis furcata - Sargassum thunbergii - Hizikia fusiformis at intertidal zone, and Caulerpa okamurae - Gelidium amansii - Chondrus ocellatus - Ecklonia stolonifera - Sargassum horneri - Gracilaria textorii at subtidal zone. These result indicates that the marine algal species and biomass of 1 m and 5 m depths in subtidal zone are greater than intertidal zone, and Ecklonia stolonifera and Sargassum spp. are the dominant species of Yokjido.