• 제목/요약/키워드: conservation population

검색결과 578건 처리시간 0.031초

Biological Control Strategy of Uzi Fly in Sericulture

  • Singh, R.N.;Saratchandra, Beera
    • International Journal of Industrial Entomology and Biomaterials
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    • 제6권2호
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    • pp.125-132
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    • 2003
  • Uzi fly (Exorista bombycis Louis) is one of the major larval endo-parasitoid of silkworm (Bombyx mori). It causes extensive damage to sericulture industry. The application of synthetic organic pesticides has tremendous impact on minimizing pest population but their overuse and frequent misuse and high sensitivity towards the silkworms, has forced the entomologists to search for alternatives to chemical control, which is safe to silkworm, environment and farm workers. Biological control continues to offer exciting possibilities for the control of fly pest population. It is environmentally safe alternative to chemical control and offering a long-term protection. Several potential hymenopteran parasitoids have been screened. Among successful natural enemies, Nesolynx thymus, Trichomalopsis apanteloctena, Trichopria sp., Brachymeria lasus, Pediobius sp., Spalangia sp., Spilomicrus karnatakensis and Dhirhinus sp. are important. It is essential to predict accurately the efficacy of these natural enemies in a new habitat prior to its introduction. The important desirable attributes of these potential parasitoids viz., host searching capacity, specificity, power of increase and fitness and adaptability of the parasitoid in new environment has been recorded. Results of the host parasitoid interaction indicate that the aging of the host function as a factor that influence the host finding efficiency of the parasitoid. It is highly scored with 15-20 hrs old pupa of the host. However, aging of the parasitoid does not significantly affect it. The sex ratio is female biased which is advantageous from biological control point of view, Biological suppression methods involving conservation and utilization of natural enemies have been discussed in detail.

Estimating Population Density of Leopard Cat (Prionailurus bengalensis) from Camera Traps in Maekdo Riparian Park, South Korea

  • Park, Heebok;Lim, Anya;Choi, Tae-Young;Lim, Sang-Jin;Park, Yung-Chul
    • Journal of Forest and Environmental Science
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    • 제33권3호
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    • pp.239-242
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    • 2017
  • Although camera traps have been widely used to understand the abundance of wildlife in recent decades, the effort has been restricted to small sub-set of wildlife which can mark-and-recapture. The Random Encounter Model shows an alternative approach to estimate the absolute abundance from camera trap detection rate for any animals without the need for individual recognition. Our study aims to examine the feasibility and validity of the Random Encounter Model for the density estimation of endangered leopard cats (Prionailurus bengalensis) in Maekdo riparian park, Busan, South Korea. According to the model, the estimated leopard cat density was $1.76km^{-2}$ (CI 95%, 0.74-3.49), which indicated 2.46 leopard cats in $1.4km^2$ of our study area. This estimate was not statistically different from the previous leopard cat population count ($2.33{\pm}0.58$) in the same area. As follows, our research demonstrated the application and usefulness of the Random Encounter Model in density estimation of unmarked wildlife which helps to manage and protect the target species with a better understanding of their status.

Does Natural Disasters Have an Impact on Poverty in East Java, Indonesia?

  • SANTOSO, Dwi Budi;AULIA, Dynda Fadhlillah
    • The Journal of Asian Finance, Economics and Business
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    • 제10권1호
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    • pp.57-66
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    • 2023
  • There is a strong association between poverty levels and the probability of natural disasters. East Java, however, exhibits a distinct pattern. While the rate of poverty is declining, natural disasters are becoming more severe. Considering that East Java is an area with a high risk of natural disasters and a high poverty rate, this study aims to estimate the effect of environmental preservation and the magnitude of the impact of disasters as measured by the Disaster Risk Index (IRBI) on poverty. The 3SLS model is used on secondary data from 38 districts/cities from 2015 to 2021 as an analytical database. Based on the estimation results, there are 3 findings in this study: (i) the role of government, population development, and economic activity have a strong influence on nature conservation; (ii) nature conservation has a strong influence on disaster risk; and (iii) the disaster risk index has a strong effect on poverty. As a result, areas with a high level of disaster risk have a slower rate of poverty reduction. The role of this research is to show the need for the government's role in improving the quality of natural disaster mitigation anticipation, economic activity, and the role of the population in a sustainable manner.

Current Status of the Ecosystem at the Nakdong River Estuary and Management Plan (낙동강하구의 생태계 현황과 관리방안)

  • Sangwook Han;Kwangjin Cho;Pyoungbeom Kim;Haeseon Shin
    • Journal of Environmental Science International
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    • 제32권12호
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    • pp.943-953
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    • 2023
  • This study analyzed the ecological characteristics of the wetland protection area at tthe Nakdong River through vegetation and biota surveys, which showed that brackish water meets fresh water, a unique ecological environment has been created, biodiversity is high, and diverse habitats are distributed. Eleven plant communities, including four woody communities and seven grass communities, are distributed along the coast, and a total of 514 species, including 11 endangered wildlife species, were identified in terms of species diversity. Among them, the species diversity of the Eulsuk-do area was found to be relatively higher than that of other Barreir Islands areas. The presence of a population of Sterna albifrons on Sinja-do and a population of Eremias argus on Jinwo-do, an area outside the boundaries of the wetland protection area, confirmed the conservation value of the wetlands and the need to expand the boundaries of the wetland protection area. It is judged that this information can be used as basic information for a systematic conservation and management plan for the wetland protection area at the Nakdong River Estuary and as basic data to support the establishment of a policy.

Change of Seoul's Downtown Planning: Focusing on Urban Conservation from the 1960s to the 1990s (서울시 도심 계획 방식의 변화: 1960년대부터 1990년대의 도시보전을 중심으로)

  • Rhee, Bum-Hun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제21권9호
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    • pp.39-48
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    • 2020
  • The purpose of this study was to understand changes in Seoul's downtown planning from the 1960s to 1990s. The approach was examined by classifying its formation process though urban conservation. The effects of modernization and urbanization on Seoul's downtown planning were as follows. In the 1960s, Seoul attempted to decentralize urban functions due to excessive population. In the 1970s, a policy to diversify urban functions according to Gangnam development was enacted. In the 1980s, the existing downtown declined, and the sub-downtown grew with changing urban functions. In the 1990s, the identity of the existing downtown was recognized through the Seoul Memorial Project. This study also analyzed downtown planning efforts concerned with urban conservation. First, the physical aspects of existing buildings and street facilities were maintained. Second, the spatial aspects for the maintenance of surrounding areas were proposed. Fourth, the social aspects for accessibility by Seoul citizens was improved. This analysis demonstrates the concept of urban conservation based on physical-spatial-social aspects.

Genetic Diversity in Three Populations of Hibiscus hamabo(Malvaceae) in Jeju Island, Korea (제주도 황근(Hibiscus hamabo) 집단의 유전적 다양성)

  • Kim, Young-Dong;Kim, Ki-Joong;Kim, Sung-Hee;Kim, Hyeong-Tae
    • Korean Journal of Plant Taxonomy
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    • 제37권2호
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    • pp.115-129
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    • 2007
  • Using internal transcribed spacer (ITS) sequences and inter-simple sequence repeats (ISSRs) data, genetic diversity of a rare species, Hibiscus hamabo Siebold & Zucc. was examined for 3 populations in Jeju Island, Korea. A total of 14 nucleotide (excluding 3 ambiguous nucleotide) site variation in the ITS was observed from 18 individuals (Population 1, Hadori), which differed up to 13 bp in pair-wise comparison. On the contrary, the ITS sequences of all individuals in Populations 2 and 3 were identical. Genetic diversity estimates including Nei's gene diversity (h) generated by ISSR data were substantially high in Population 1 compared to other two populations. Low genetic variation in Populations 1 and 2 is considered due to genetic drift (bottleneck effect) and limited gene flow in these populations. Considering the differences in genetic diversity, protection of the Population 1(Hadori) is very critical for in situ conservation of Hibiscus hamabo in Korea. If ex situ conservation is required, making the full use of Population 1 will be most efficient.

The Basic Theories for Restoration of Fragmented Habitats (파편화된 서식처 복원을 위한 기초이론 고찰)

  • Kim, Myoung-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • 제4권2호
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    • pp.52-61
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    • 2001
  • At least, there are intense pressures on the natural habitats from various disturbance, including urbanization, extension of industrial area, and road construction. These human land use result in fragmentation of landscape and natural habitat. The ecological consequences of habitat fragmentation include the direct effects of habitat loss and the indirect effects of reduced inter-patch dispersal. The decline of biological diversity has been rapidly declined by the habitat loss and fragmentation. Conservation strategists should consider not only the habitat amount of that must be preserved, but also the spatial configuration of habitat across the landscape. But, the paucity of available data for most species forces landscape ecologists to develop the concept, model, and theory. The developed theories are often misused in academic papers and practical applications. The development history, presumption of concept, model, theory is ignored. This tendency have leaded to failure of landscape restoration and the use of theory in conservation practice have come under increasing attacks. This paper will highlight the ecological theory that have proven the most influential in landscape ecology, restoration and conservation : the theory of island biogeography, the theory of nested subset analysis, minimum viable population(MVP), the theory of metapopulation dynamics. And, it find the problem and usefulness of four theory in application to real world. Consequently, the understanding of theoretical implication about landscape ecological theory is required. We must carefully apply the theory after examining the problem and availability of various theory because of no existence of only one general theory.

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Vegetation characteristics, conservation and ecotoursim strategies for water spider(Argyroneta aquatica) in small marsh, Korean Natural Monument (물거미가 서식하는 천연기념물 습지의 식생학적 특성과 보전 및 생태관광화 방안)

  • You, Young-Han;Yi, Hoon-Bok
    • Journal of Wetlands Research
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    • 제11권2호
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    • pp.99-106
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    • 2009
  • Water spider(Argyroneta aquatica Clerck) is only spider that live under aquatic water. In korea, water spider distributed only in Undari Wetland, Yeochon County, Kyongii Proviance, where it is designated as Natural Monument. I counted the population density, analysed the ecological traits such as actual vegetation map, and suggested conservation strategy and eco-tourism planning for water spider. The population mean density of water spider was one individual/$m^2$ and 8,000 individuals/ha. The wetland inhabited by water spider was characterized by high water level fluctuation between rainy season and dry ones. Wetland plant community was dominated by Phragmites australis and Leersia oryzoides var. japonica with submersed plant, Utricularia japonica. It is need to supply water for inhibiting terrestial succession trend during the dry season and to connect three fragmented wetlands through ecological corridor. Also, It was suggested that ecotourism planning is important for conserving this wetland.

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A unique genetic lineage at the southern coast of China in the agar-producing Gracilaria vermiculophylla (Gracilariales, Florideophyceae)

  • Hu, Zi-Min;Liu, Ruo-Yu;Zhang, Jie;Duan, De-Lin;Wang, Gao-Ge;Li, Wen-Hong
    • ALGAE
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    • 제33권3호
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    • pp.269-278
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    • 2018
  • Ocean warming can have significant negative impacts on population genetic diversity, local endemism and geographical distribution of a wide range of marine organisms. Thus, the identification of conservation units with high risk of extinction becomes an imperative task to assess, monitor, and manage marine biodiversity for policy-makers. Here, we surveyed population structure and genetic variation of the red seaweed Gracilaria vermiculophylla along the coast of China using genome-based amplified fragment length polymorphism (AFLP) scanning. Regardless of analysis methods used, AFLP consistently revealed a south to north genetic isolation. Populations at the southern coast of China showed unique genetic variation and much greater allelic richness, heterozygosity, and average genetic diversity than the northern. In particular, we identified a geographical barrier that may hinder genetic exchange between the two lineages. Consequently, the characterized genetic lineage at the southern coast of China likely resulted from the interplay of post-glacial persistence of ancestral diversity, geographical isolation and local adaptation. In particular, the southern populations are indispensable components to explore evolutionary genetics and historical biogeography of G. vermiculophylla in the northwestern Pacific, and the unique diversity also has important conservation value in terms of projected climate warming.

Population Trends of Wintering Whooper Swans(Cygnus cygnus) in South Korea: Data from the Winter Waterbird Census Program

  • Choi, Jieun;Kim, Ji Yoon;Do, Yuno;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • 제51권4호
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    • pp.365-372
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    • 2018
  • The Wintering Waterbird Census of Korea was started in 1999 and monitors 200 major migratory sites in South Korea. Waterfowl counts have been undertaken for more than 20 years since; however, a limited number of studies have analyzed the temporal patterns of waterfowl population. In this study, we analyzed population size changes of wintering whooper swan (Cygnus cygnus) at 112 monitoring sites from 2001 to 2018. The average number of whooper swans was $4,296{\pm}42.66$ and there was a trend for an increase in population size across the survey period. We found that the population in the Nakdong River Estuary, one of the major wintering sites over 18 years (26.22% of the national population), had rapidly decreased (-0.77% per year). Conversely, the whooper swan population in the Junam Reservoir and Sihwa Lake increased (+1.64%, +0.54% per year, respectively). Estuaries showed the highest dominance of whooper swans among the five different habitat types, accounting for 32.13% of the population. Reservoir/lakes had 30.60% of the total population and reclaimed lakes(18.24%), river (13.11%), and coast (5.93%) followed. The annual distribution of the whooper swan population in South Korea has been affected by various habitat conditions resulting from human activities and urbanization. To better understand the complex factors that can cause rapid changes in wintering waterfowl populations, it is necessary to integrate the data from the bird census program with environmental conditions to conduct in-depth pattern analyses over longer time periods.