• Title/Summary/Keyword: habitat density

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A Study on the Habitat Mapping of Meretrix lyrata Using Remote Sensing at Ben-tre Tidal Flat, Vietnam (원격탐사를 활용한 베트남 Ben-tre 갯벌의 Meretrix lyrata 서식지 매핑 연구)

  • Hwang, Deuk Jae;Woo, Han Jun;Koo, Bon Joo;Choi, Jong-Kuk
    • Korean Journal of Remote Sensing
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    • v.37 no.5_1
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    • pp.975-987
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    • 2021
  • Potential habitat mapping of Meretrix lyrata which is found in large parts of South East Asian tidal flat was carried out to find out causes of collective death. Frequency Ratio (FR) method, one of geospatialstatistical method, was employed with some benthic environmental factors; Digital elevation model (DEM) made from Landsat imagery, slope, tidal channel distance, tidal channel density, sedimentary facesfrom WorldView-02 image. Field survey was carried out to measure elevation of each station and to collect surface sediment and benthos samples. Potential habitat maps of the all clams and the juvenile clams were made and accuracy of each map showed a good performance, 76.82 % and 69.51 %. Both adult and juvenile clams prefer sand dominant tidal flat. But suitable elevation of adult clams is ranged from -0.2 to 0.2 m, and that of juvenile clams is ranged from 0 to 0.3 m. Tidal channel didn't affect the habitat of juvenile clams, but it affected the adult clams. In the furtherstudy, comparison with case of Korean tidal flat will be carried out to improve a performance of the potential habitat map. Change in the benthic echo-system caused by climate change will be predictable through potential habitat mapping of macro benthos.

Study on the Relationship between the Forest Canopy Closure and Hyperspectral Signatures

  • Lin, Chinsu;Chang, Chein-I
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.72-74
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    • 2003
  • Forest canopy density is an ideal representative of the forest habitat situations. It can directly or indirectly depict the canopy structure and gap size in the forestland, thus could be applied to assessment of wildlife’s diversit y. Since population survey of vegetation and wildlife diversities is a key issue for sustainable forest ecosystem management, many research efforts have been focused on forest canopy density using multispectral data in the last two decades. Unfortunately, prediction of canopy density using large scaling remote sensing data remains a challenging issue. Due to recent advances in hyperspectral image sensors hyperspectral imagery is now available for environmental monitoring. In this paper, we conduct experiments to monitor complicated environments of forestland that can be captured by using hyperspectral imagery and further be analyzed to test a prediction model of forest canopy density. The results show that 95% of canopy density could be well described by using 2 difference vegetation indices (DVIs), which are difference of blue and green reflectances rband_100-rband_150 and difference of 2 short wave infrared reflectancse rband_406-rband_410 With the wavelengths of band no. 100, 150, 406, and 410 specified by 462.39 nm, 534.40 nm, 918.22 nm and 924.41 nm respectively.

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Estimating Population Density of Leopards in Semi-Arid habitat, Western India

  • Randeep Singh;Puneet Pandey;Qamar Qureshi;Kalyanasundaram Sankar;Paul R. Krausman;Surendra Prakash Goyal
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.4 no.2
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    • pp.72-78
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    • 2023
  • The leopard (Panthera pardus) is one of the most widespread felids worldwide. Despite their wide distribution, reliable data on leopard population densities are still inadequate for conservation and management strategies in different landscapes. In the present study, we estimated leopard density using camera traps in the Ranthambhore Tiger Reserve (RTR), Rajasthan, India, between December 2010 and February 2011, where leopards coexist alongside a high density of tigers (Panthera tigris), a larger predator (RTR). A sampling effort of 4,450 trap days was made from 178 camera trapping stations over 75 days, resulting in 46 suitable photo captures (25 right flanks and 21 left flanks). In total, 18 individuals (7 males, 8 females, and 3 unknown sexes) were identified using the right flanks, and the estimated leopard density was 8.8 (standard error=2.8) individuals/100 km2. Leopard density appeared to respond to small prey (<50 kg weight) richness. As this is the first systematic study to provide baseline information on leopard density in RTR, it could form a baseline for comparison in future investigations.

Research on the Correlation Between Rail Transit Entrances and Urban Form in High-Density Areas

  • Dongzhu Chu;Hong Su
    • International Journal of High-Rise Buildings
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    • v.12 no.1
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    • pp.35-47
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    • 2023
  • The transport system and its infrastructure are not only the fundamental means of sustaining the operation of contemporary cities, but also important drivers for the evolution of urban form. Rail transit, critical to improving the operational efficiency and optimizing the spatial layout in cities, is one of the critical conditions for high-density areas with limited land and concentrated resources to be compact to take on complex challenges. As a node element of infrastructure, rail transit entrances are the most important points connecting the rail transit system with urban space. Although influenced by urban form, their quantity and location also influence and shape the evolution of urban space form. Based on the development gap of high-density areas in various contexts, focusing on various rail transit stations in Asia, this research analyzes the correlation between rail transit entrances and peripheral high-density urban form in a delicate, dynamic and granular way. The research considers both horizontal and vertical perspectives, in combination with the urban evolution process in time series, to explore the development trend of high-density urban form in Asia from the aspect of correlation, and building a new foundation for research on urban form, suitable for different types of cities.

The autecology of Zostera marina and Z. japonica at Sagumi Bay in the southwestern coast of Korea (남해 서부연안의 사구미 만에서 거머리말(Zostera marina)과 애기거머리말(Z. japonica)의 개체생태학)

  • Ok, Jae-Seung;Lee, Sang-Yong
    • Journal of Environmental Science International
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    • v.23 no.9
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    • pp.1563-1572
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    • 2014
  • The autecology of the Zostera marina and Z. japonica was studied in populations growing in the same locality (Sagumi Bay, southwestern coast of Korea). Environmental factors and plant characteristics were examined monthly from August 2008 to September 2011. Along intertidal zone, Z. japonica (0.1-0.5 m above mean lower low water, MLLW) occurred above Z. marina (0.5-2.5 m MLLW). Tidal exposure at low tide during day was the highest in the spring and the lowest in the summer. Underwater Irradiance showed seasonal fluctuation that was the highest in spring and summer caused by tidal pattern. Strong seasonal patterns in water temperature appeared to control the seasonal variations in morphology, biomass and leaf growth. The seasonal pattern of Z. japonica resembled that of the Z. marina in morphological characteristics, above-and below-ground biomass, whereas it differed in shoot density and leaf elongation. Despite some similarities in seasonal growth patterns, the patterns of Z. japonica were lagged by 2 month of Z. marina. Seasonal variation in the above biomass of Z. marina was caused by changes in density and plant size, whereas that of Z. japonica was mainly caused by changes in shoot density. Zostera marina was more sensitive to high temperatures than Z. japonica, and the increasing water temperature during the summer became the factor that inhibits the growth of the Z. marina. Zostera Japonica, there is no clear change according to the amount of the light. It is because its habitat locates above that of Zostera marina so that the amount of the light that is necessary to growth is enough and in this condition, any preventing factor does not seem to work at all. Although underwater light getting into Zostera marina's habitat is very low level and there is no any hindrance to the survival of them, it prevents them from their productivity a bit.

The impact of sand addition to an intertidal area for the development of the Manila clam, Ruditapes philippinarum habitat on benthic community structure (the case of Ojjeom tidal flat in Gonam-myeon, Taean-gun) (바지락 치패발생장 조성을 위한 모래살포가 저서동물 군집구조에 미치는 영향 (태안군 고남면 옷점 갯벌 사례))

  • Yoon, Sang Pil;Song, Jae Hee;Choi, Yoon Seok;Park, Kwang Jae;Chung, Sang Ok;Han, Hyoung Kyun
    • The Korean Journal of Malacology
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    • v.30 no.3
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    • pp.259-271
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    • 2014
  • This study was conducted to investigate the impact of sand addition to an intertidal for the development of the Manila clam habitat on benthic community structure. For this, we focused on the spatio-temporal changes in the surface sediment condition and benthic community structure including Manila clam before and after the event. Study site was the lower part of Ojjeom tidal flat in Gonam-myeon, Taean-gun where sand added to on July 2010. We set three stations at each of sand adding area (experimental plot) and non sand-adding area (control plot) and did sampling works ten times from June 2010 to October 2011. Directly after the event, surface sediments changed to very coarse sand, but the state was not maintained over two months because of seasonal sedimentation and finally got back to the original grain sizes in eight months. The number of species and density were temporarily reduced right after the event and polychaetes such as Sternaspis scutata, Ampharete arctica were most negatively affected by the event. However, the number of species and density quickly recovered from the reduction in four to six weeks owing to the recolonization by the existing species and species in the vicinity of the plot. However, despite the recovery of ecological indies, species composition was continuously changed from one to another, thereby community structure stayed unstable condition, especially in some stations with finer sediment in their original condition. After sand addition, density of Manila clam was prominently increased at only one station with coarser sediment in its original condition.

Feces Distribution of Otter(Lutra lutra) Population in Seosi Stream (서시천에서 수달(Lutra lutra) 배설물의 분포에 관한 연구)

  • Kim, Woo Yuel;Jin, Seon Deok;Bing, Gi Chang;Park, Chi Young;Lee, Doo Pyo
    • Korean Journal of Heritage: History & Science
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    • v.43 no.1
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    • pp.118-127
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    • 2010
  • From January to December of 2006, the distribution characteristics and density of otter(Lutra lutra ) feces were studied at Seosi stream, a tributary of Seomjin river, in Gurye-gun, Jeollanam-do. During the study period, the number of excretion site, old feces, and new feces were observed six times in seven habitat sections of the stream. As the result, 222 excretion sites, 662 old feces (converts to 718 per 60 days), and 364 new feces were observed. All of these were observed the most in January. Mean density per 500m was 26.9 for excretion sites, 88.6 for old feces, and 44.4 for new feces. Monthly changes in the number of excretion site and feces per section showed that otters have no specific preference to a habitat section of Seosi stream over the year.

Implementation of Occupant Density and Walking Pattern Measurement for Emergency Evacuation and Safety in High-Rise Multi-Purpose Facilities

  • Lee, Myung Sik
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.409-415
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    • 2018
  • Recently, many countries around the world began to show interest in safety against terrorism, fire, and natural disasters. This study aimed to propose a quantitative measurement system for emergency evacuation and safety for various kinds of terrorism and fire within high-rise multi-purpose facilities, which can measure the pedestrians' ordinary walking patterns in the concourse with the highest pedestrian volume out of all the spaces within multi-story buildings, predict pedestrians' evacuation walking lines when a sudden disaster breaks out, and analyze the gait coefficient, occupant density, and evacuation behavior time.

Study of a Three-Dimensional and Multi-Functional Urban High-Rise Complex in the High-Density Environment: Design Practice of Yiwu World Trade Center

  • Li, Linxue;Hou, Miaomiao;Zhang, Qi
    • International Journal of High-Rise Buildings
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    • v.8 no.1
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    • pp.37-47
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    • 2019
  • Facing the challenges of urban form and space quality in a high-density environment, the paper puts forward the development trend of three-dimensional and multi-functional design for an urban high-rise complex, and analyzes the design methods of establishing an urban landmark, including multi-functional composition, three-dimensional space integration, three-dimensional traffic organization and energy flow programming. Meanwhile, combined with the specific design case of Yiwu World Trade Center, the practical experience of designing a high-rise complex in China's medium-sized cities is analyzed.

A Study on Setting up Conservation Areas through Habitat Value Assessment of Developing Area (개발예정지역에서의 서식지 가치평가를 통한 보전지역 설정에 관한 연구)

  • Park, Yong-Su;Kim, Dae-Heui;Cho, Dong-Gil;Kim, Kwi-Gon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.3
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    • pp.26-38
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    • 2006
  • For both a healthy environment and sustainable development, we frame a habitat assessment method, concerning biodiversity and physical characteristics. With the method, we set up and extract conservation areas from Peace Valley Resort Development Areas which can function as habitats. Absolute and relative assessment items which are the size of area, habitation of species with conservation value, distribution of communities, functions of habitats, ratio of non-native plants, connectivity of habitats, vegetation layers of forests and age of forests, and water systems are considered on newly extracted conservation areas, and the habitat value assessment was calculated on the items in a 3-point scale. By comparing and examining 3 existing proposals for extracted conservation areas, we assess existing proposals, make an alternative proposal, and try to verify the possibility of applicability to extracted conservation areas. Proposal A and C must not be adopted since almost all conservation areas would be developed in the proposals. Proposal B, consisting of 53% development areas and 47% non-development areas, does not have enough development areas, so high density building arrangements should be encouraged in order to preserve conservation areas. Therefore, proposal B would be the best in ecological terms among the 3 proposals, if 3 conditions are considered : 1) new extracted conservation areas should be conserved; 2) 10~15m wide green-zones on both sides of the water system, which can play a role as ecological corridors, should be considered in development areas; 3) building arrangement should not interrupt the ecological corridors.