• Title/Summary/Keyword: island ecosystem

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Characteristics, Threats and Management of Philippine Wetlands (필리핀 습지의 특성, 위협 및 관리)

  • Sespene, Shemelyn M.;Maniquiz-Redillas, Marla;Kim, Lee-Hyung;Choo, Yun-wook
    • Journal of Wetlands Research
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    • v.18 no.3
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    • pp.250-261
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    • 2016
  • The Philippines is a naturally water-rich archipelago capable of sustaining its ecological goods and providing services and needs of its people. Several waterbodies have been declared as natural wetlands in the country supporting the needs of community like water and food. In this study, 65 natural wetlands were considered including six sites that were identified as 'Wetlands of International Importance' such as Naujan Lake National Park, Agusan Marsh Wildlife Sanctuary, Olango Island Wildlife Sanctuary, Tubbataha Reefs Natural Park, Las $Pi{\tilde{n}}as-Para{\tilde{n}}aque$ Critical Habitat and Ecotourism Area and Puerto Princesa Subterranean River National Park. There are 22 wetland types presented in this research categorizing the Philippine wetlands. Philippine wetlands are now facing tremendous challenges such as land use conversion, abuse of resources, pollution coming from domestic, industrial and agricultural activities, and climate change. This paper provides an overview of Philippine wetlands in terms of their characteristics and components, impacts in the ecosystem, and the challenges they are dealing with. Moreover, the preservation measures that the government and private agencies implements to these wetlands were discussed and assessed. The enforcement of local and national laws concerning wetlands is found to be inadequate resulting in poor quality wetlands. The preservation and utilization of these wetlands can be maximized with a voluntary participation of whole Philippine community.

A Fundamental Study on the Effect of Ocean Fertilization by Deep Sea Water (해양심층수에 의한 해역 비옥화 효과에 관한 기초 연구)

  • Shiokari, Megumi;Tabeta, Shigeru;Kato, Takayoshi
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.3
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    • pp.198-207
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    • 2012
  • In this study, we investigated the effect of ocean fertilization by deep sea water, using an ecosystem model which contains not only phytoplankton but also zooplankton. The model is based on NEMURO which consists of eleven compartments - two species of phytoplankton, three species of zooplankton, $NO_3$, $NH_4$, $Si(OH)_4$, particulate organic nitrogen, dissolved organic nitrogen and particulate silicon. We introduced nitrogen cell quota in the both species of phytoplankton, and silicon cell quota in the large phytoplankton in addition to the eleven compartments of NEMURO. We made the experiment at Izu Oshima Island in order to investigate the effect of ocean fertilization. In this experiment, we could not find clear differences between the cases with and without deep sea water. We investigated the causes of the experiment results by the model simulations. One of the causes was high concentrations of nutrients in surface seawater used in the experiment. Another was that the increase of total concentration of inorganic nitrogen does not necessarily accelerate the photosynthetic rate because inorganic nitrogen uptake rate is related to the ratio of $NO_3$ to $NH_4$. Because the model can represent the results of the experiment, we investigated the effect of ocean fertilization by deep sea water using this model. We found that the effect of ocean fertilization hardly appeared when the interval of the addition of deep sea water was too short, or the amount of deep sea water was too much. It is supposed that if the addition of deep sea water is too frequent or too much, the dilution of plankton's concentrations will exceed the effect of promoting phytoplankton's photosynthesis.

Effects of Artificial Vegetation Island on Fish Fauna (인공수초섬이 어류상에 미치는 영향)

  • Byeon, Myeong-Seop;Park, Hae-Kyung;Jeon, Nam-Hui;Choi, Myeong-Jae;Kong, Dong-Soo
    • Korean Journal of Ecology and Environment
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    • v.40 no.1
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    • pp.103-109
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    • 2007
  • To investigate the effects of artificial vegetation island (AVI) on fish distribution, we compared fish fauna from artificial vegetation island (AVI) area, which installed in 2000, natural vegetation area (NVA) and vegetation-free area (VFA) at Kyungan Stream area of Lake Paldang from Jul. to Nov., 2005. Results showed that 11 families 23 genera 24 fish species were distributed in the AVI and NVA. Squalidus japonicus coreanus, a small-size fish which generally lives at the downstream, dominated absolutely in the individual numbers. However, only 6 families 11 genera 12 species of fishes caught at the VFA, and dominant fishes were Hemibarbus labeo and Erythroculter erythropterus, a medium to large-size migratory fishes which live in mid-depth of water column. The dominance index was high at the AVI (0.778) and NVA (0.868), whereas the diversity index and evenness index were high at the VFA. Fish distribution at AVI was similar to that of the NVA in numbers of species, indicating that the AVI could playa role as spawning and inhabitation zone to a variety of fishes. We believe that AVI may be used for a restoration of the damaged and disturbed littoral ecosystem.

The Characteristics and Distribution of the Surface Sediment Grain Size of Nakdong River Deltaic Barrier Islands (낙동강 삼각주연안 사주섬 표층퇴적물의 입도특성과 공간적 분포)

  • Kim, Sung-Hwan;Rhew, Ho-Sahng;Shin, Young-Ho
    • Journal of the Korean association of regional geographers
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    • v.13 no.1
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    • pp.43-53
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    • 2007
  • Rapid geomorphic changes occur in Nakdong River deltaic coast which is composed of deltaic barrier islands and tidal flats. We investigate the pattern of these rapid geomorphic changes by analyzing the distributions of sediment grain size characteristics. The distributions of sediment grain size characteristics analysis is a very efficient method to explain geomorphic changes of deltaic barrier islands. In sediments from Jinwoo Island, Sinja Island, and Doyo Island which are composed of Nakdong River deltaic coast, mean particle size increases to onshore direction and become coarser in tidal inlets. All sediments are very well sorted. Though almost sediments show little negative skewness, several sediments from tidal inlets show negative skewness. These results provide that the stronger and more regular energies affect Nakdong River deltaic coast and make fine sediments selectively move toward tidal inlets. Because of this mechanism, the recurved spits of deltaic barrier islands enlarge.

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Comparison of Nekton Assemblage Structures Between Estuary and Inshore Waters on the Mid-Western Coast of Korea (서해 하구역과 연안역 유영생물의 군집구조 비교)

  • Hwang, Sun-Do;Lee, Woo-Joo;Im, Yang-Jae
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.3
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    • pp.149-159
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    • 2012
  • To elucidate the species compositions of estuarine and inshore fauna and compare productivities between them, catch were collected by bag nets in the Han River estuary off Ganghwa Island and the inshore waters off Jangbong Island for 24 hours at the spring tide from March to December 2010. Community structures of nekton assemblages were different with area, month, taxonomic groups. Although the diversity of estuarine nekton assemblage was lower than that of inshore nekton assemblage, the productivity of nekton assemblage in estuary was higher than that in the inshore waters. Nekton assemblages were distributed according to habitat environment: the estuarine species, Coilia mystus, Chelon haematocheilus, Collichthys lucidus were prominent in the Han River estuary off Ganghwa Island, and marine species, Thryssa kammalensis, Sardinella zunasi, Portunus trituberculatus were prominent in the inshore waters off Jangbong Island. Palaemon gravieri, Exopalaemon carinicauda, Synechogobius hasta were inhabited in both waters. The health assessment of estuarine ecosystem based on scientific research will be contributed to the effective management of estuary with determination of order and direction in policy.

Floristic study of Aphaedo Island in Shinan-gun, Jeollanam-do, Korea (압해도(전라남도 신안군)의 식물상)

  • HYUN, Jin-Oh;NA, Hye Ryun;KIM, Yeonsu;HAN, Byungwoo
    • Korean Journal of Plant Taxonomy
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    • v.48 no.1
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    • pp.65-99
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    • 2018
  • We investigated vascular plants of Aphaedo Island in Shinan-gun, Jeollanam-do, Korea. By referring to voucher specimens collected over the course of 28 days from May of 2011 to March of 2016, a total of 451 taxa were identified and grouped into 102 families, 294 genera, 413 species, 6 subspecies, 30 varieties, and 2 forms, of which 9 taxa were classified as endangered or rare, including Albizia kalkora, Salomonia oblongifolia, and Centranthera cochinchinensis var. lutea. A total of 59 taxa were identified as regional indicator plants. Six taxa were endemic to Korea, including Hepatica insularis, Indigofera koreana, and Lespedeza maritima. Three taxa (Rumex acetosella, Aster pilosus, and Hypochaeris radicata) among 52 naturalized taxa were ecosystem-disturbing plants as designated by the Ministry of the Environment. The results of preceding floristic research before and after the inauguration of the Aphaedaegyo (bridge) were used to analyze changes in the number of naturalized species on Aphaedo Island.

Comparison of the foraging efficiency between adult and immature Eurasian Oystercatchers (Haematopus ostralegus osculans) during the breeding season on Yubu Island (번식기 유부도 일대에 서식하는 검은머리물떼새 (Haematopus ostralegus osculans) 성체와 미성체의 섭식 능력 비교)

  • Lee, Sang-Yeon;You, Young-Han;Jeong, Gilsang;Choi, Yu-Seong;Joo, Sungbae
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.483-492
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    • 2019
  • During the breeding season, both adults and immature Eurasian Oystercatchers (Haematopus ostralegus osculans) were observed to feed on prey, such as gastropods (Umbonium thomasi) and bivalves, at the tide water line around Yubu island in Korea. To determine differences in the foraging efficiency between the adult and immature birds, we recorded the feeding behavior using digiscoping with a telescope and a smartphone. We compared the pace, the prey search rate, the proportion of prey search techniques, the feeding success rate, the handling time, and the heads-up rate between the adult and immature birds. There were significant differences in the proportion of prey search techniques when gastropods were consumed and in the prey search rate and heads-up rate when bivalves were consumed but there were no significant differences in feeding success rates. Therefore, although the immature birds on Yubu Island were inferior to adults during the breeding season and they lacked the proficiency to locate prey, their overall foraging efficiency was similar to adults. This was considered to be due to the continuous eating of bivalves during the wintering season, which requires a high level of foraging efficiency.

Emergy Carrying Capacity of Sungap-do, An Uninhabited Island in Korea (무인도서 선갑도의 에머지 환경수용력 평가)

  • Kang, Dae-Seok
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.13 no.1
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    • pp.60-67
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    • 2010
  • For sustainable use of the resources of uninhabited islands of Korea, their ecological economic potential needs to be fully integrated into their management policy and the carrying capacity of the islands should be evaluated before using or developing them. The emergy methodology was used to evaluate the ecological economic value and carrying capacity of Sungap-do which is an uninhabited island in Incheon, Korea. The system boundary for the emergy evaluation of the island included the sea area within 1km from the high tide level, following the management boundary for the uninhabited islands of Korea stipulated in the Law on the Conservation and Management of Uninhabited Islands. The total renewable emergy input to Sungap-do was $1.04{\times}10^{20}$ sej/yr from tidal energy. The annual ecological economic contribution of the island was evaluated high at 29.9 billion Em₩/yr. If Sungap-do were developed to the national average, its carrying capacity was 6,586 persons at the current living standard of Korea. The carrying capacity of Sungap-do for the long-term sustainability scenario was 2,337 persons at the same living standard as in the developed scenario. When only emergy contribution of the land area was considered, the carrying capacity of Sungap-do sharply decreased to 14 persons for the developed scenario and 5 persons for the long-term sustainability scenario. The carrying capacity of the uninhabited islands of Korea including Sungap-do, thus, needs to be considered from the initial stage of utilization or development projects to sustain the ecosystem benefits and their sustainable uses.

The Distribution of the Exotic Species, Ophraella communa LeSage (Coleoptera, Chrysomelidae) and Their Applicability for Biological Control against Ragweed Ambrosia artemisiifolia L. on Jeju Island (제주도에서의 외래종 돼지풀잎벌레 분포 및 외래종 돼지풀 제거를 위한 생물학적 방제 대상종으로의 활용 가능성)

  • Kim, Do-Sung;Oh, Ki-Seok;Lee, Yeong-Don;Lee, Su-Young;Lee, Heejo;Kim, Hyun-Jung;Kim, Dong-Eon
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.437-445
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    • 2017
  • An analysis of recent studies and a field survey were conducted to investigate the distribution of the exotic species Ophraella communa LeSage (Coleoptera, Chrysomelidae) and the results' applicability for biological control against ragweed, which disturbs the island's ecosystem. The ragweed beetle (O. communa) can be found anywhere on the host plant Ambrosia artemisiifolia L., which grows in Jeju Island. Moreover, ragweed beetles possess the following characteristics: a high host plant specificity, a high-temperature resistance, an excellent mobility, and multivoltinism. Ragweed is extensively distributed and gradually expands its habitat further on Jeju Island. For this reason, it is recommended to take advantage of O. communa for the biological control of ragweed instead of pesticides or direct removal, considering that Jeju is endowed with many natural reserves and unique insular traits.

Ecological Restoration and Environmental Impact Assessment for the Realization of the Central Theme, Preservation, Suggested in the National Anthem of Korea (생태복원과 환경영향평가: "애국가"에 나타난 '보전'의 이념 구현을 중심으로)

  • Kim, Eun-Shik;Hong, Sun-Kee
    • Journal of Environmental Impact Assessment
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    • v.17 no.1
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    • pp.25-45
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    • 2008
  • This review was made to discuss the issues of ecological restoration and environmental impact assessment (EIA) related to the preservation of natural environment, the central theme expressed in the National Anthem of Korea. The authors notice that the key word or the central philosophy contained in the verses of the National Anthem of Korea is the preservation of national land and eternal identity for future generations, which is thought to be pursued through the attainment of ecological sustainability. A conceptual model for the sustainable management of natural ecosystems was suggested for the efficient utilization and the preservation of them, whose activities should be promoted by those of conservation and restoration instead of destructive development and negligence, respectively. Here, the preservation of natural environment can be directly pursued through the restoration of degraded ecosystems and landscapes and the utilization of natural environment can be directly pursued through the conservation of natural resources and wise management of natural ecosystems and landscapes. After reviewing the major characteristics and activities of the restoration of degraded ecosystems and landscapes, discussion was further extended to points for the promotion of the EIA activities. To point out some of them, it is needed for the public to better understand the nature of sustainable management of natural environment, for the society to put extensive energy and resources in the restoration of degraded ecosystems and landscapes, and for the government to install higher levels of ministries than that of the Ministry of Environment in dealing with the issues related to the 'preservation' of national land, people, culture and the security of the sustainability for future generations, where EIA and strategic environment assessment (SEA) can directly contribute to the sustainability of the country and future generations.