Analyzing the Effect of River Ecosystem Fragmentation by Bridges on Changes in the Wintering Population of Whooper Swans (Cygnus cygnus): Targeting the Nakdong River, Busan

Soo-Dong Lee(Soo-Dong Lee),Chung-Hyeon Oh(Chung-Hyeon Oh),Bong-Gyo Cho(Bong-Gyo Cho),Min-Hwa Jin(Min-Hwa Jin),Gyoung-Sik Park(Gyoung-Sik Park) 인간식물환경학회 2022 인간식물환경학회지 Vol.25 No.5

Background and objective: Fragmentation of river ecosystems is expected to affect biodiversity loss, but bridge construction is proceeding without consideration in urban areas. This study was conducted to determine the effect of internal environmental factors and river ecosystem fragmentation caused by bridge construction on the population of wintering whooper swans (Cygnus cygnus) in the Nakdong River of Busan Metropolitan City, a key wintering site for whooper swans. Methods: To compare the wintering population according to the distance between bridges, we surveyed and analyzed the current status of the population by period, distance between bridges, and land cover. One-way ANOVA and post-hoc test were conducted to confirm whether the differences in the environmental factors of the wintering sites, such as the distance between bridges, land cover status, and the number of wintering individuals, were statistically significant. Results: 83.6-94.7% of the wintering population in the lower Nakdong River were observed in Sec. 2 (Nakdong River Estuary Bank-Seobusan Nakdong River Bridge, 5.3 km) and Sec.4 (Gamjeon-Iron Bridge-Nakdong River Hwaengdansugwan Bridge, 3.6 km). As for the distance between the feeding and resting places of whooper swans and the bridges, whooper swans used the waterside and wetlands at an average distance of 1,147.5 m (10.9-2,611.2 m) from the bridge. Conclusion: Considering the weight of male swans and the presence of young individuals, as well as disturbance factors such as the noise and speed of vehicles crossing the bridges, it is necessary to maintain at least a 4 km distance between bridges for stable wintering. In addition, since fragmentation of river ecosystems has been confirmed to have an adverse effect on biodiversity, it would be desirable to keep the ecosystem intact and connected.

한강하구에 도래하는 재두루미의 서식지이용 현황

강태한 ( Tae Han Kang ),유승화 ( Seung Hwa Yoo ),김화정 ( Hwa Jung Kim ),이기섭 ( Ki Sup Lee ) 한국환경생태학회 2009 한국환경생태학회지 Vol.23 No.3

2006년부터 2008년까지 월동기(10월~3월)동안 한강하구에 도래하는 재두루미의 서식지 이용현황을 조사하였다. 월동개체군은 평균 106.6개체(SD=27)가 관찰되었으며, 2008년 1월초에 최대 140개체가 관찰되었다. 재두루미는 농경지와 갯벌을 같이 이용하였으며, 월동기 동안 농경지와 갯벌의 이용율에 유의한 차이를 보이지 않았다(Mann-Whitney test. p=0.4). 시기별 이용율은 월동초기에는 농경지의 이용율이 높았으며, 월동후기에는 갯벌의 이용율이 높았다 (Mann-Whitney test. 월동초기: p<0.01, 월동후기: p<0.01). 월동중기에는 농경지와 갯벌의 이용율에 차이가 없었다. 농경지는 홍도평, 평동, 이화동, 장항논을 모두 이용하였으며, 홍도평의 이용율이 높았다. 각 농경지간 이용율은 월동초기와 중기에 유의한 차이를 보였다(Kruskal-wallis test. p<0.05). 갯벌은 김포대교~누산리 구간을 이용하였으며, 김포대교~일산대교 상류구간의 이용율이 높았다. 각 구간별 이용율은 시기별로 유의한 차이가 있었다(Kruskal-wallis test. p<0.01). This study was conducted to investigate the habitat use of White-naped Cranes Grus vipio in Han river estuary during the wintering period from 2006 to 2008 (October~March). The average numbers of wintering White-naped Cranes were 106.6±21.7(Mean±SD) individuals, and the highest number of 140 individuals were recorded in the early January, 2008. The wintering habitat use of White-naped Cranes between rice field and mudflat was not significantly different (Mann-Whitney test. p=0.40) during the wintering period. However, White-naped Cranes spent more time on the rice field in the early winter (p<0.01), and on the mudflat in the late winter(p<0.01). There was not a difference of the habitat use rate on middle winter. White-naped cranes used four different sites of rice field: Hongdopyoung, Pyoungdong, Ihwadong and Janghang rice fields. Among them, Hongdopyoung was the main foraging site. There was significant differences of habitat use ratio in the early and mid winter (Kruskal-wallis test. p<0.01). White-naped Cranes used mudflat area from Gimpo Daegyo to Nusanri of Han river estuary. Especially, they preferred four sites from Gimpo Daegyo to Ilsan Daegyo more than the other sites. Habitat use rate of mud flats were significantly different among each site during the wintering period (Kruskal-wallis test. p<0.01)

블루베리의 내한성 평가 및 목재수분계측기를 이용한 동해피해 진단

김기덕(Ki-Deog Kim),이준구(Jun-Gu Lee),류명상(Myeong-Sang Ryu),유동림(Dong-Lim Yoo),권영석(Young-Seok Kwon),이종남(Jong-Nam Lee) (사)한국생물환경조절학회 2012 생물환경조절학회지 Vol.21 No.4

외국에서 도입한 블루베리의 내한성을 평가하고, 목재수분계측기가 월동 중 블루베리 가지의 동해피해를 간편하고 신속하게 진단하는데 활용할 수 있는지를 알아보기 위하여 수행되었다. 월동 중 블루베리의 가지의 고사율은 0~100%로 다양하게 나타나 품종별 내한성의 차이가 컸다. 블루베리 가지의 저온처리에 따른 TTC검정에서 품종별 OD값은 ?40℃ < ?21℃ < 4℃ 순으로 처리온도가 낮을수록 낮게 나타났다. 블루베리 가지의 저온처리에 따른 가지절단면의 색의 검정은 가지고 사율에 의한 내한성과 다른 결과와 차이가 있었다. 목재수분계측기에 의해 측정된 살아있는 블루베리 가지의 월동 중 최저 수분함량은 약 15%였으며, 월동 중 블루베리 가지의 위치별 수분함량은 나무 아랫부분일수록 높고 가지 끝으로 갈수록 낮았으나, 봄으로 접어들면서 가지 끝의 수분함량이 점점 높아져 20~40% 범위로 측정되었다. 월동 중 동해피해를 받은 가지는 점점 건조되어 수분함량이 5% 이하로 낮아졌다. 동해를 받은 블루베리 가지의 수분함량은 14% 수준 이하일 것으로 추정되며, 목재수분계측기가 블루베리 가지의 동해피해를 현장에서 신속하게 진단하는데 활용될 수 있을 것으로 기대된다. This study was conducted to evaluate on the freezing tolerance of introduced blueberry cultivars in Korea and to investigate availability of portable timber moisture meter for simple and rapid diagnosis of blueberry-shoot damage by freezing during wintering. Frost tolerance of blueberry cultivars showed big difference that rates of blueberry-shoot death were widely distributed from about 0% to 100% after wintering. Optical density in TTC reduction of blueberry twig treated low temperature was low in order of ?40℃ < ?21℃ < 4℃. Hardiness evaluation of visible injury in the cross-sectional surface color did not agree with that of rates of blueberry-shoot death during wintering. Lowest water content of blueberry stem measured by timber moisture tester during wintering was about 15%. During wintering, water contents of blueberry stems were higher at lower part of tree, but were low at end part of stems, and then when the blueberry grew again for spring, the water content gradually increased to 20~40%. Water content of blueberry stem with freezing injury during wintering decreased to under 5% by desiccation. Therefore it is assummed that the moisture content of blueberry stem injured by freezing during wintering was about under 14%, and it is expected that portable timber moisture meter could be available for rapid diagnosis of blueberry freezing injury in field.

인천해안지역의 난온대성 상록활엽수 겨울철 생장에 영향을 미치는 미기후 요인

김정철,김도균 한국조경학회 2019 韓國造景學會誌 Vol.47 No.5

This study investigated the feasibility of wintering evergreen broad-leaf trees in the Incheon coastal area through a climate analysis. The coldest monthly mean air temperature ranged from —2.9℃∼—1.6℃. The warmth index of the coastal area of Incheon ranged from 98.89℃·month-109.03℃·month, while the minimum air temperature year ranged from —13.9℃∼—3.6℃. This proved that the Incheon coastal area was not suitable for evergreen broad-leaf trees to grow as the warmth index ranges from 101.0℃·month∼117.0℃·month, and the temperature year-round is —9.2℃ or higher. This suggests the coastal areas of Incheon is not suitable for the growth of evergreen broad-leaf trees, however some evergreen broad-leaf trees lived in some parts of the area. Wind speed reduction and temperature effect simulations were done using Landschaftsanalyse mit GIS program. As a result of the simulations of wind speed reduction and temperature effects affecting the evergreen broad-leaf trees, it was discovered that a coastal wind velocity of 8.6m/sec was alleviated to be 5m/sec∼7m/sec when the wind reached the areas where evergreen broad-leaf trees were present. It was also discovered that species that grew in contact with buildings benefited from a temperature increase of 1.1℃∼3.4℃ due to the radiant heat released by the building. Simulation results show that the weather factors affecting the winter growth damages of evergreen broad-leaved trees were wind speed reduction and local warming due to buildings. The wind speed reduction by shielding and local warming effects by buildings have enabled the wintering of evergreen broad-leaved trees. Also, evergreen broad-leaved trees growing in the coastal area of Incheon could be judged to be gradually adapting to low temperatures in winter. This study reached the conclusion that the blockage of wind, and the proximity of buildings, are required for successfully wintering evergreen broad-leaf trees in the coastal area of Incheon. 본 연구는 인천해안지역의 난온대성 상록활엽수 겨울철 생장에 영향을 미치는 미기후 요인을 시뮬레이션 기법을 통해 도출하였다. 인천 해안지역 서구 오류동∼남동구 고잔동의 온량지수는 98.9℃·month∼109.0℃·month이었고, 1월 평균기온 —2.9℃∼—1.6℃, 최한월 최저기온 —13.9℃∼—3.6℃ 수준으로, 상록활엽수 분포기준인 온량지수 101.0℃․month∼117.0℃․month, 최한월 최저기온 —9.2℃이하로 상록활엽수가 생장하기 부적합한 지역으로 나타났다. 상록활엽수가 생장하는 공간에 도달하는 풍속의 저감정도와 가온효과에 대한 시뮬레이션을 실시한 결과, 상록활엽수 생장공간에서는 겨울 북서풍이 건축물 등에 의해 해안풍속이 8.6m/sec에서 도달풍속은 5~7m/sec로 완화되었고, 건축물 1m 이내에서는 건축물 복사에너지의 영향으로 1.1℃~3.4℃ 가량의 가온효과가 나타났다. 시뮬레이션 결과, 상록활엽수의 겨울철 생장피해에 영향을 미치는 기후요소는 풍속으로, 차폐에 의한 풍속저감과 함께 건축물에 의한 국부적 가온효과가 상록활엽수의 겨울생장이 가능한 것으로 추정되었다. 또한 인천 해안지역에 생장하고 있는 상록활엽수는 중부지방의 겨울철 저온에 점진적으로 식물이 적응하는 순화의 과정으로 판단할 수 있었고, 기온이 —18.0℃ 이하의 겨울한파에 견디는 내동능력과 바람에 의한 증발산을 견딜 수 있는 동건해(凍乾害)에 내성이 상록활엽수 겨울 생장을 좌우하는 것으로 나타났다.

인공증식 방사 저어새와 야생 저어새의 서식지 이용 및 이주

유성연,권인기,유정칠,이기섭,황종경,박종현 한국조류학회II 2023 한국조류학회지 Vol.30 No.2

This study evaluated the wild adaptation of released Black-faced Spoonbills using a headstarting strategy. Rings were attached to five captive-reared spoonbills and five wild spoonbills born in Gaksiam. Additionally, transmitters were attached to three released spoonbills and five wild spoonbills to compare habitat use, migration, and survival rates through re-sight and tracking data. As a result of the tracking data, two of the released spoonbills and five wild spoonbills used the tidal flat on southern Ganghwa Island after release or fledging for migration. One released spoonbill used the tidal flat near Donggeom Island and northern Yeongjong Island. Among the tracked spoonbills, one released spoonbill and three wild spoonbills had migrated from the West Sea to China. After migration, the released spoonbill wintered in Liyang Bay between Hangzhou Bay and Taizhou Bay, which were previously known spoonbill wintering site. One of the spoonbills, which was released with only an attached color band, wintered in Tai Lake, Suzhou, China. Tracking and re-sight record analyses revealed that, two released spoonbills died during the first wintering period. One wild spoonbill died before wintering, and one died during wintering. The survival rate of the released spoonbills was 60%, and the survival rate of the wild spoonbills was 60% one year after release or fledging. Headstarting for spoonbills is still in its early stages, and there is a limit to evaluating its effectiveness because of the small number of released individuals. This study revealed that the released spoonbills succeeded in wintering and migrating, and there is a possibility for future development of this strategy. If headstarting is further improved and expanded, it is expected to contribute to the population reinforcement of breeding sites with low reproductive success rates. 본 연구는 선제적보전전략 적용 하에 인천광역시 강화군에 위치한 저어새 번식지 각시암에서 알을 구조하여 인공 증식한 4개체와 송도 갯벌에서 구조한 유조 1개체를 원 서식지에 방사 후 야생 적응 여부를 평가하기 위해 수행하였다. 특히, 방사 개체 중 3개체와 각시암에서 태어난 야생 저어새 유조 5개체에게 위치추적기를 부착하여 얻은 자료와 가락지 재관찰 정보를 수집하여 서식지 이용, 이주 행동, 생존율을 비교하였다. 위치추적 결과 방사 개체 중 2개체와 야생개체들은 방사 및 이소 이후부터 이주하기 전까지 강화도 남단 갯벌을 이용했고, 나머지 방사 개체는 동검도 인근 갯벌과 영종도 북단 갯벌을 이용했다. 위치추적기를 부착한 개체들 중 방사개체 1개체와 야생개체 3개체가 서해를 건너 중국으로의 이주에 성공했다. 위치추적 방사개체는 이주 후 기존 저어새 월동지로 알려진 항저우만과 타이저우만 사이의 리양 만에서 월동했으며, 가락지만 부착한 방사개체 중 1개체는 중국 쑤저우시 타이호에서 월동한 것이 확인되었다. 위치추적 및 가락지 재관찰 기록 분석 결과 방사개체들은 첫 월동기에 2마리가 폐사했고, 야생개체들은 월동기 이전에 1개체, 월동기에 1개체가 폐사하여 1년이 지난 시점에서 방사된 저어새와 야생 저어새들의 생존율은 각각 60%로 나타났다. 저어새를 대상으로한 선제적보전전략 연구는 아직 초기 단계로 현재까지 방사한 개체수가 적어 그 효과를 평가하는데는 한계가 있으나, 본 연구 결과 방사된 저어새가 이주와 월동에 성공하여 향후 확대 적용시 번식성공률이 낮은 번식지의 개체군을 보강하는데 기여할 수 있을 것으로 기대된다.

Over-Wintering Stage of Citrus Leaf Miner (Phyllocnistis citrella Stainton) in Citrus Orchards in Jeju Area

Soon Hwa Kwon,Rok Yeun Hwang,Cheol Woo Choi,Jae Wook Hyun,Dong Soon Kim 한국응용곤충학회 2018 한국응용곤충학회 학술대회논문집 Vol.2018 No.04

The citrus leaf miner (CLM) is a of important citrus pests in Jeju island, but it’s not clear about ecology of over-wintering in Jeju. We investigated the developmental stage to know how the CLM overwinters in 20 sites. And we investigated the mortality of larvae, pupae and adult stage of CLM in open citrus cultivated field December, 2017 to April 2018 and growth chamber conditions(from –10 to 5 ℃). As a result, no larvae and adult survived open field during winter. We concluded that the CLM usually overwinters as pupa during winter.

Current Status and Importance of Grus vipio Coming to Hangang Estuary

Kang, Tae-Han,Yoo, Seung-Hwa,Lee, Doo-Pyo,Lee, Ki-Sup national science museum of korea 2009 Journal of Korean nature Vol.2 No.2

This study was conducted to understand the arrival trends of Grus vipio, which wintered in the Hangang estuary, from October to March next year from 2004 to 2008. During four wintering periods, the number of individuals of Grus vipio arriving at the estuary was average 507.5${\pm}$10.8 (n=4). The arriving sites were Seongdong IC and Janghang IC. Seongdong IC was a stopover while Janghang IC was a final destination for wintering. In Seongdong IC, 424.3${\pm}$149.4 (n=4) individuals on average arrive while 153.8${\pm}$63.3 (n=4) individuals arrive at Janghang IC. The number of individuals arriving at the Hangang estuary accounts for 8.6 percent of the living total and 2.0 percent of the total wintering individuals.

Varroa mite and climate change influence winter survival of honey bees (Apis mellifera) in Korea

Yong Soo Choi,You Young Jo,Dong Won Kim,Su Bae Kim,Bo Sun Park,Dae Gun Oh,Min Woong Shon,Akongte Peter Njukang,Chang Hun Lee 한국응용곤충학회 2023 한국응용곤충학회 학술대회논문집 Vol.2023 No.10

Honey bees are crucial pollinators for agricultural and natural ecosystems, but are experiencing heavy mortality in Korea due to a complex suite of factors. Extreme winter losses of honey bee colonies are a major threat to beekeeping but the combinations of factors underlying colony loss remain debatable. Finding solutions involves knowing the factors associated with high loss rates. To investigate whether loss rates are related to Varroa control and climate condition, we surveyed beekeepers in korea after wintering (2021–2022 to 2022–2023). The results show an average colony loss rate of 46%(2022) and 17%(2023), but over 40% colony loss before wintering at 2022. Beekeepers attempt to manage their honey bee colonies in ways that optimize colony health. Disentangling the impact of management from other variables affecting colony health is complicated by the diversity of practices used and difficulties handling typically complex and incomplete observational datasets. We propose a method to 1) Varroa mite population Control by several methods , and 2) Many nursing bee put in hive before wintering.

Effect of Fertilizer and Straw Mulching on Winter Discoloration and Spring Regrowth of Lawn Grasses

Lee, Jin-Wook,Lee, Ho-Jin The Korean Society of Crop Science 2001 Korean journal of crop science Vol.46 No.2

This experiment evaluates wintering ability to maintain green color of lawn grasses during winter and investigates the effects of top dressing of fertilizer on improving green color during regrowth. Kentucky blue-grass could maintain green color and leaf chlorophyll content better than tall fescue and creeping bentgrass in winter. All three grasses in this experiment have shown the excellent wintering ability. In enhancing the recovery of green color at the early stage of regrowth, the mulching effect with rice straw was highly significant for creeping bentgrass. Green color recovery in grasses during its regrowth was better at the top dressing plots than at the plots without top dressing, but when fertilizer application levels were increased, green color in lawn grass did not significantly change. Although green color in tall fescue, Kentucky bluegrass, and Korean lawngrass could be maintained during summer, the green color of creeping bentgrass is reduced significantly with high temperature. Top dressing after winter and mowing improved leaf chlorophyll content and green color in tail fescue and Kentucky bluegrass significantly. However, Korean lawngrass did not respond significantly with increased levels of fertilizer.

돌나무의 가을 삽목번식에 미치는 삽목용토 및 시기의 영향

안정호(Jeong Ho Ahn),최성식(Seong Sig Choe),배종향(Jong Hyang Bae),이승엽(Seung Yeob Lee) (사)한국생물환경조절학회 2007 생물환경조절학회지 Vol.16 No.2

돌나물의 가을 삽목번식을 위한 적정 삽목용토와 삽목시기를 조사하기 위하여, 농가에서 손쉽게 구할 수 있는 밭흙, 강모래와 훈탄을 혼합한 삽목용토의 효과를 조사하였다. 밭흙과 모래를 1:1 또는 2:1 (v/v)로 혼합하여 사용하는 것이 활착, 지상부 생육 및 뿌리발달이 양호하여 경제적이었다. 선발된 삽목용토(밭흙:모래 =2:1)를 이용하여 10×5 ㎝ 간격으로 가을 노지삽목을 실시한 결과, 9월 초중순에 히는 것이 뿌리 및 지상부 생육이 양호하고, 월동전 충분한 rosette를 확보할 수 있어 안정적이었다. 따라서 가을 노지삽목 한계기는 9월 20일로서, 삽목시기가 늦을 경우, 이듬해 봄철 적정 수량을 확보를 위하여 삽수의 수량을 25-30% 늘려 밀식재배하는 것이 바람직하다. For autumn cutting of Sedum sarmentosum, the influences of bedsoil and cutting date were investigated. Among six kinds of bedsoils mixed upland soil, carbonized rice and sand, the mixture with upland soil and sand (1:1 and 2:1, v/v) showed excellent root and shoot growth. The mixtures with upland soil and carbonized rice were lower rooting than the mixture with upland soil and sand. In field condition, autumn cutting was conducted with 10×5 ㎝ space using the mixture with upland soil and sand (2:1, v/v) at intervals of 10 days from September 1 to October 10. Both root and shoot growth were significantly decreased by delayed date. In cutting from early to middle September, root and shoot growth, and number of rosette before wintering were desirable for shoot production next spring. The safety date to autumn cutting before wintering was on September 20 in field condition. If autumn cutting is late than September 20, the number of scion has increased 25 - 30% to secure a full rosette before wintering. The results could provide the beneficial information for cutting propagation of S. sarmentosum under field condition in autumn.