• 한국환경생태학회지
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• 제30권6호
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• pp.977-985
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• 2016

환경부 지정 멸종위기 II급 종인 남생이의 복원을 위하여 개체증식 프로그램들을 개발해왔지만, 남생이의 번식생리에 대한 이해는 여전히 부족한 상태이다. 본 연구에서는 2014년 11월부터 2015년 10월 사이에 동면을 한 개체와 동면을 하지 않은 개체를 이용하여 성호르몬, 여포와 알의 수와 크기, 암 수간의 행동상호작용의 계절적 변화를 연구하였다. 비록 동면 여부에 따라 다소의 편차는 있었지만, 암컷의 혈청 에스트라디올 농도는 7월부터 증가하기 시작하여 8월-10월에 최고 농도를 보였으며, 수컷의 테스토스테론의 농도는 8-9월에 최고 농도를 보였으며, 3월에 가장 낮았다. 동면을 한 암컷들은 5월초에서 7월 중순 사이에 완전히 발달한 알을 가지고 있었으며, 산란은 6월 초순부터 7월 하순 사이에 이루어졌다. 반면, 동면을 하지 않은 암컷들은 이른 4월부터 이른 6월 사이와 8월 중순에서 11월 하순 사이에 알을 가지고 있었으며, 산란은 6월초, 10월 중순, 2월 초에 이루어졌다. 이러한 결과는 동면이 여포와 알의 정상적인 발달에 매우 중요한 역할을 함을 보여준다. 행동연구에서 암 수간의 구애행동을 포함하는 행동상호작용은 8월 하순부터 증가되어 10-11월에 최대를 보였다. 연구결과는 남생이의 짝짓기 기간이 성호르몬의 증가와 직접 연계되어 있지만, 여포와 알의 발달은 그렇지 않다는 것을 보여준다. 이러한 연구결과는 멸종위기종인 남생이의 성공적인 번식프로그램을 운영하는데 매우 중요하게 사용될 것으로 판단된다.

• 한국어류학회지
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• 제29권4호
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• pp.235-243
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• 2017

본 연구는 2012년 1~7월까지 경기도 양평군 흑천 일대에서 한강납줄개의 산란 특성에 관한 연구를 실시하였다. 한강납줄개는 물의 흐름이 느리고 달뿌리풀과 버드나무의 수생식물이 많은 곳의 모래와 뻘의 하상구조를 보이는 지점을 선호하였다. 연령은 6월 기준으로 13~22 mm는 당년생, 체장 30~45 mm는 만 1년생, 45~55 mm는 만 2년생, 55~70 mm 이상군은 만 3년생 이상으로 추정되었다. 조사기간 동안 암수 성비는 1 : 0.80로 나타났고 산란기는 3월부터 6월까지로 추정되었다(수온 $11.0{\sim}26.2^{\circ}C$). 한강납줄개는 작은말조개 Unio douglasiae sinuolatus에 비점착성 알을 산란하였고 확인된 알 및 및 자어수는 1~22 ($5.8{\pm}5.51$)개였다. 반새 위치에 따른 알 및 자어수는 왼쪽 외반새 1~9 ($2.7{\pm}2.16$)개, 왼쪽 내반새 1~2 ($1.5{\pm}0.71$)개, 오른쪽 내반새 1~5 ($1.8{\pm}1.79$)개, 오른쪽 외반새 1~22 ($5.8{\pm}5.51$)개로 나타났다.

• 한국환경생태학회지
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• 제25권4호
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• pp.490-497
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• 2011

본 연구에서는 강원도 홍천 지역에 자생하는 노랑갈퀴(Vicia chosenensis) 개체군을 대상으로 개체군 내 결실에 영향을 미치는 요소를 규명하기 위해 생물적, 무생물적 환경 요소를 조사하였다. 자생지 내 교목 층은 신갈나무가 우점하는 가운데 소나무가 드물게 존재하고 있었으며, 관목층은 생강나무, 조록싸리가 우점하고 있었다. 초본류는 결실이 된 노랑갈퀴와 미 결실된 노랑갈퀴 주변에 공통적으로 우산나물이 가장 많이 분포하였고(21%), 넓은잎외잎쑥(13~18%)과 큰기름새(10~11%)가 다음으로 높은 빈도수를 나타내었다. 자생지의 토양 특성을 분석한 결과, 토양 수분은 20.4~21.9%, 유기물 함량은 8.6~14.9%, 전질소함량은 0.3~0.5%, 유효인산은 12.7~16.9 parts per million, 양이온 치환용량은 22.5~28.5$cmol_ckg^{-1}$, 평균 산도는 pH 5.3~5.5로 나타났다. 대부분의 노랑갈퀴는 빛이 많이 들어오는 곳에 위치하고 있었으며, 결실이된 개체가 미 결실된 개체보다 수관의 열림 정도가 크고 상대적으로 광량이 풍부한 숲틈에 분포하였다. 따라서 노랑갈퀴의 개체군 유지를 위해서는 간벌 등을 통해 상층목을 적절히 제거함으로서 숲틈이 유지될 수 있도록 하여야 할 것이다.

• Ocean and Polar Research
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• 제37권1호
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• pp.37-47
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• 2015

The effects of low salinity (fertilization success and larval survival) on the limpet Cellana grata were studied at early stages of development using the marine bioassay technique. It was shown that, under normal conditions for development from fertilization to the post veliger stage, the salinity must be not less than 20.0~35.0 psu. However, the fertilization rate and larval survival of C. grata was obviously reduced at 5.0 psu and 10.0 psu, respectively. Mass mortality was estimated to occur at <20.0 psu (48-h $EC_{50}=19.54psu$) and the survival rate of normal veliger larvae decreased with experimental time during exposure. No observed effective concentration (NOEC) and lowest observed effect concentration (LOEC) of post veliger were estimated at 30.0 psu and 25.0 psu, respectively, during 48-h exposure. The tolerance limits of the test species to salinity revealed various concentration ranges of salinity, which may reflect the physiology and ecology of the initial development stages of C. grata. These results demonstrate that reduced salinity is detrimental to the reproductive success and larval survival of C. grata, and if salinity is lowered by natural or anthropogenic sources during spawning, this would lead to decreased reproductive success and larval settlement.

• The Korean Journal of Ecology
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• 제14권2호
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• pp.211-230
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• 1991

The germinatin of e. annuus continued from the middle ofmay to mid-october. The maximum germination occurred on the mid-july. The period bloom of was distingushed amongs the different growth forms ; a orm pr of biennial and a form of pr perennial flowering from the mid-may to mid-september, and a form ps biennial blossom from the beginning of October to earlynovember. the dispersal of seed for(a form pr)occurred from early June to the mid-september. A rotte, germinating from summer to autumn, could classified into several growth forms; individuals without a critical leaf area for bolting until september and October, become a form ps of biennial, whicth did not proceed toreproductive growth unitl the next year, even thought wintering. individuals flowered on 3 years after germination become a form pr of perennial. The growth formular of aform pr of bennial, grown in a pot was w=20.2[1+$3.36{\times}10^3$(-0.062t)]$^{-1}$. The maximum relative growth rate(rgr) was 0.062g/g/day and the maximum net assimlation rate(nar) 0.089g/g/day. Therelative growth among each organ was shown as R=0.12 $T^{1.15}$between the avove-ground part(t) and the below- ground part(r). the relation between the avove-ground part(t) and the ratio of stem weight(wi) was ws/wi=2.56 $T^{0.35}$. n.p.k. was largely distributed on a leaf throughoutthe total growth period. while growing, it tended to decrease on the vegetative organ gut vice versa on the reproductive organ. however, nitrogen was more widely distributed on a leaf then in the reproductive organ.

• Journal of Ecology and Environment
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• 제41권9호
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• pp.256-264
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• 2017

Background: The aim of this study was to clarify the relationship between the sexual reproduction and the resource allocation in a natural Polygonatum humile population grown in a temperate mixed forest gap. For this aim, the plant size, the node which flower was formed, the fruiting rate, and the dry weight of each organ were monitored from June 2014 to August 2015. Results: Firstly, in 3-13-leaf plants, plants with leaves ${\leq}8$ did not have flowers and in plants with over 9 leaves the flowering rate increased with the number of leaves. Among plants with the same number of leaves, the total leaf area and dry weight of flowering plants were larger than those of non-flowering plants. The minimum leaf area and dry weight of flowering plants were $100cm^2$ and 200 mg, respectively. Secondary, the flowers were formed at the 3rd~8th nodes, and the flowering rate was highest at the 5th node. Thirdly, cumulative values of leaf properties from the last leaf (the top leaf on a stem) to the same leaf rank were greater in a plant with a reproductive organ than in a plant without a reproductive organ. Fourthly, fruit set was 6.1% and faithful fruit was 2.6% of total flowers. Biomasses of new rhizomes produced per milligram dry weight of leaf were $0.397{\pm}190mg$ in plants that set fruit and $0.520{\pm}0.263mg$ in plants that did not, and the difference between the 2 plant groups was significant at the 0.1% level. Conclusions: P. humile showed that the 1st flower formed on the 3rd node from the shoot's base. And P. humile showed the minimum plant size needed in fruiting, and fruiting restricted the growth of new rhizomes. However, the fruiting rate was very low. Thus, it was thought that the low fruiting rate caused more energy to invest in the rhizomes, leading to a longer rhizome. A longer rhizome was thought to be more advantageous than a short one to avoid the shading.

• 한국동물생명공학회지
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• 제38권2호
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• pp.62-69
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• 2023

Background: Research on the reproductive physiology of Water and Sika deer, an endemic in Korea, still needs to be completed. This study analyzed the ovarian development and morphological characteristics of wild Water deer and Sika deer. Methods: Water deer and Sika deer ovaries were collected from the Korean Peninsula and Russia-Korean Peninsula border during the estrus and pregnancy seasons, respectively. And, morphological and physiological analysis and immunohistochemistry were conducted to confirm the detection of Ca²⁺ and assess the morphological changes in the ovaries. Results: The results of morphological analysis of ovaries during pregnancy and estrus, the development of the corpus luteum and follicles of Water deer showed similar patterns to other mammals. In contrast, the corpus luteum of Sika deer differed in tissue morphology and composition from Water deer. Ca²⁺ related to tissue metabolism was detected in the theca cells zone of Water deer on the estrus and was highly detected in the luteum cells zone during pregnancy. The hormone receptor protein expression patterns were generally higher in the ovaries of Water deer on the estrus and the pregnancy than in Sika deer. The expression of LH receptor was relatively low in the lutein cell zone, unlikely that of Water deer. The expression of VEGF was also different from Water deer, and the response in Sika deer was relatively very low compared to Water deer in expressing all proteins-related development. Conclusions: Therefore, the results of the study were shown that the composition of the corpus luteum of Sika deer is not clear compared to Water deer, and there are many differences in the functional and morphological formation of the corpus luteum.

• Journal of Ecology and Environment
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• 제47권3호
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• pp.134-145
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• 2023

Background: The flowering and fruiting periods play an important role in biological processes. The deciduous dipterocarp forest is an important forest type in Thailand, however the phenological studies are still limited, particularly in different plant life forms. Thus, the present study focused on the flowering and fruiting phenology of herbs, climbers, shrubs, and trees in the deciduous dipterocarp forest at Lampang province of Northern Thailand. Field visits were made to record plant life forms and observe reproductive phenological events at monthly intervals from November 2018 to October 2019 and September to December 2020. Results: The phenological observations were based on 126 species of 45 families and 102 genera. Flowering and fruiting periods showed similar patterns in herbaceous plants, climbers, and shrubs. Most of these species produced flowers and fruits from the end of the rainy season (October) to the winter season (November-January). Whereas most of flowering and fruiting trees were found from the summer season (March-April) to the beginning of the rainy season (May-June). Most of the dry-fruited species occurred during the dry period (winter and summer seasons), while the majority of fleshy-fruited species dominated in the wet period (rainy season). The statistical analysis supported the phenological patterns of flowering and fruiting in the present study. There were significant negative correlations between the number of flowering and fruiting species and temperature. The number of flowering and fruiting species is significantly impacted by the interaction between seasons and plant life forms. Conclusions: Plant life form seems to be the important factor that affects the different phenological patterns in the studied plants. The abiotic and biotic factors play major roles in reproductive phenology. However, long-term study and in-depth phenological observations are necessary for better understanding.

• 한국발생생물학회지:발생과생식
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• 제12권2호
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• pp.169-181
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• 2008

2006년 1월부터 12월까지 한국 서해안 무안군 자운도 주변해역에서 안강망으로 채집한 병어, Pampus argenteus를 대상으로 조직학적 조사 및 형태 측정에 의해 번식 생태를 조사하였다. 병어는 자웅이체이며, 난소는 한 쌍의 낭상구조를 하고 있으며, 수많은 난소소엽으로 구성되어 있다. 정소는 엽상구조를 하고 있으며, 수많은 정소소엽으로 구성되어 있다. 암 수 개체들의 생식소중량지수(GSI), 간중량지수(HSI), 비만도지수(CF) 값들의 월별 변화는 2월(초기 성장기)부터 8월 (회복기 시작)까지는 생식소 발달단계와 아주 유사한 경향을 보이며 변하였다. 이들 지수값의 변화로부터 암컷과 수컷 개체들의 방란, 방정은 5월부터 7월까지 일어나는 것으로 추정되었다. 병어의 생식주기는 암컷의 경우, 초기성장기(2$\sim$3월), 후기성장기(3$\sim$4월), 성숙기(3$\sim$7월), 완숙 및 산란기(5$\sim$7월), 회복 및 휴지기(7$\sim$2월)로 구분되었다. 수컷의 경우는 성장기(2$\sim$4월), 성숙기(3$\sim$6월), 완숙 및 방정기(5$\sim$7월), 회복 및 휴지기 (7$\sim$2월)로 구분되었다. 월별 난경 조성 빈도 분포 변화로 보아 병어의 산란빈도수는 한 산란기 중 한 개체가 적어도 2회 또는 그 이상 산란하는 다회 산란종으로 추정되는 춘하계 산란종이다. 체장당 절대포란수의 총 난수는 체장이 커짐에 따라 절대포란수의 총 난수는 증가되는 경향을 보였으며, 상대포란수(cm 당)의 총 난수도 체장이 커짐에 따라 상대포란수(cm 당)의 총 난수가 증가되는 경향을 보였다. 체중당 절대포란수의 총 난수는 체중이 증가됨에 따라 절대포란수의 총 난수는 증가되는 경향을 보였다. 그러나 체중당 상대포란수(g 당)의 총 난수는 체중이 증가됨에 따라 증가되나, 일정 체중 이상으로 커지면, 오히려 체중 증가에 따라 상대포란수의 총 난수가 감소하는 경향을 보였다. 군성숙도 50%에 해당하는 체장은 12.1$\sim$15.0 cm(만 1세 이상에 해당)이었고, 군성숙도 100%에 해당되는 체장은 18.1$\sim$21.0 cm(만 3세에 해당)이었다. 따라서 병어는 만 1세 이상이 되면 전체 개체의 50%가 성숙에 도달하여 재생산(산란)에 가담할 수 있는 것으로 추정되었다.

• 식물분류학회지
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• 제46권2호
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• pp.129-148
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• 2016

Plant species on oceanic islands comprise nearly 25% of described vascular plants on only 5% of the Earth's land surface yet are among the most rare and endangered plants. Conservation of plant biodiversity on islands poses particular challenges because many species occur in a few and/or small populations, and their habitats on islands are often disturbed by the activity of humans or by natural processes such as landslides and volcanoes. In addition to described species, evidence is accumulating that there are likely significant numbers of "cryptic" species in oceanic archipelagos. Plant systematists, in collaboration with others in the botanical disciplines, are critical to the discovery of the subtle diversity in oceanic island floras. Molecular data will play an ever increasing role in revealing variation in island lineages. However, the input from plant systematists and other organismal biologists will continue to be important in calling attention to morphological and ecological variation in natural populations and in the discovery of "new" populations that can inform sampling for molecular analyses. Conversely, organismal biologists can provide basic information necessary for understanding the biology of the molecular variants, including diagnostic morphological characters, reproductive biology, habitat, etc. Such basic information is important when describing new species and arguing for their protection. Hybridization presents one of the most challenging problems in the conservation of insular plant diversity, with the process having the potential to decrease diversity in several ways including the merging of species into hybrid swarms or conversely hybridization may generate stable novel recombinants that merit recognition as new species. These processes are often operative in recent radiations in which intrinsic barriers to gene flow have not evolved. The knowledge and continued monitoring of plant populations in the dynamic landscapes on oceanic islands are critical to the preservation of their plant diversity.