• Title/Summary/Keyword: habitat environments

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Comparative Study on the Development Trends of High-rise Buildings Above 200 Meters in China, the USA and the UAE

  • Qu, Jiaqi;Wang, Zhendong;Du, Peng
    • International Journal of High-Rise Buildings
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    • v.10 no.1
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    • pp.63-71
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    • 2021
  • Since 2006, the number of completed high-rise buildings over 200 meters have increased rapidly. Although there were some short-term cyclical troughs, the overall trend has still been growing. No longer constrained by technological limits, the development of high-rise buildings now depends on cooperation and compromise between social, economic, and political factors. This article extracts statistical data from the Council on Tall Buildings and Urban Habitat (CTBUH) to focus on the completion of high-rise buildings of 200 meters and above over the past 20 years from 2000 to 2019. Similarities and differences in the number, distribution, and function of high-rise buildings are analyzed, The paper also compares the impact of different political and economic environments on the development trends of high-rise buildings in China, the United States and the UAE.

Development of Habitat Suitability Index (HSI) Model for Mandarin duck (Aix galericulata) and Great spotted woodpeckers (Dendrocopos major) (도시에 서식하는 원앙과 오색딱다구리의 서식 적합성 지수(HSI) 모델 개발)

  • Park, June-Young;Song, Young-Keun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.1
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    • pp.37-51
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    • 2021
  • The purpose of this research is to develop the Habitat Suitability Index (HSI) for habitat environments of Aix galericulata (A. galericulata) and Dendrocopos major (D. major), which tend to inhabit urban environments. A. galericulata and D. major are the keystone species representing the ecosystem of wetlands and forests. Based on the analysis of their urban habitat environments, this study selects artificially adjustable levels of the environmental index in order to produce the HSI model, which can be used when either restoring or creating the urban habitats for these species. To develop the HSI, we conducted field surveys at Jungnangcheon Stream, Changgyeonggung, Jangneung, Bangbae Neighborhood Park, Gildong Ecological Park, and Seodalsan Mountain. These surveys were conducted between April and August 2020, and this period includes the breeding season of both A. galericulata and D. major. Based on our findings from the surveys, we conclude that there are six SI factors for A. galericulata. These include (1) the presence of alluvial islands, (2) waterfront vegetation cover rate, (3) type of aquatic plants for food, (4) size of forest patch, (5) type of trees in nearby forests, and (6) connectivity of waterfront and forest. We also conclude that there are five SI factors for D. major, which include (1) size of forest patch, (2) rate of broadleaf trees in forest patches, (3) type of nesting trees, (4) diameter at breast height (DBH) of nesting trees, and (5) density of dead trees. The result of this research can provide future studies with useful guidance when both (1) comparing the habitat suitability of the target species in different environments and (2) restoring or creating habitats for these species.

APPLICATION OF AQUATIC HABITAT IMPROVEMENT TECHNIQUES AT TA-CHIA RIVER IN TAIWAN

  • Tuan, Ching-Hao;Yeh, Chao-Hsien
    • Water Engineering Research
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    • v.6 no.4
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    • pp.161-168
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    • 2005
  • With characteristics of river continuum, stream ecosystems have diverse components and environments from upstream channel to estuarine area. Therefore, the habitat requirements and composition of conservative object should be well understood before applying any improvement measure. In this paper, the causes of stream habitat changes were first illustrated with the categories and principles of habitat restoration methods. The structural restoration techniques of fish habitat improvement utilized by the authors or one three-year research project starting at 1990 were then presented. Through the introductions on the project background, planning guidelines, structure design, and ecological evaluation, this paper tried to provide some effective examples of stream restoration practices that ecological expert was invited for cooperation and advising.

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Use of GIS to Develop a Multivariate Habitat Model for the Leopard Cat (Prionailurus bengalensis) in Mountainous Region of Korea

  • Rho, Paik-Ho
    • Journal of Ecology and Environment
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    • v.32 no.4
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    • pp.229-236
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    • 2009
  • A habitat model was developed to delineate potential habitat of the leopard cat (Prionailurus bengalensis) in a mountainous region of Kangwon Province, Korea. Between 1997 and 2005, 224 leopard cat presence sites were recorded in the province in the Nationwide Survey on Natural Environments. Fifty percent of the sites were used to develop a habitat model, and the remaining sites were used to test the model. Fourteen environmental variables related to topographic features, water resources, vegetation and human disturbance were quantified for 112 of the leopard cat presence sites and an equal number of randomly selected sites. Statistical analyses (e.g., t-tests, and Pearson correlation analysis) showed that elevation, ridges, plains, % water cover, distance to water source, vegetated area, deciduous forest, coniferous forest, and distance to paved road differed significantly (P < 0.01) between presence and random sites. Stepwise logistic regression was used to develop a habitat model. Landform type (e.g., ridges vs. plains) is the major topographic factor affecting leopard cat presence. The species also appears to prefer deciduous forests and areas far from paved roads. The habitat map derived from the model correctly classified 93.75% of data from an independent sample of leopard cat presence sites, and the map at a regional scale showed that the cat's habitats are highly fragmented. Protection and restoration of connectivity of critical habitats should be implemented to preserve the leopard cat in mountainous regions of Korea.

Evaluating the Restoration of a Stream in an Abandoned Mine Land via Biomass Calculation of Benthic Macroinvertebrates

  • Mi-Jung Bae;Hyeon-Jung Seong;Seong-Nam Ham;Eui-Jin Kim
    • Korean Journal of Ecology and Environment
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    • v.55 no.4
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    • pp.415-420
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    • 2022
  • It is essential that continual assessments of the impact of mine-derived water as a long-lasting burden on freshwater environments. Abundance-based evaluations of benthic macroinvertebrates have been conducted to evaluate anthropogenic disturbances and devise policies to reduce their impact. In this study, the status of a stream habitat was evaluated based on the body length and biomass weight of benthic macroinvertebrates of the family Baetidae. Following the renewal of the mining water treatment plant, the abundance of Baetidae assemblages recovered to a level comparable to that of a reference site. However, relatively low values were found for both body length and biomass weight in Baetidae species inhabiting the reddened streambed area, suggesting that the habitat has not yet been completely recovered despite the recovery of the abundance of the Baetidae assemblages. Therefore, continuous investigation and evaluation of this disturbed stream are necessary until their growth conditions of the habitat have functionally recovered.

Assessing the Habitat Potential of Eurasian Otter (Lutra lutra) in Cheonggye Stream Utilizing the Habitat Suitability Index (서식지 적합성 지수를 이용한 청계천 수달의 서식지 평가)

  • In-Yoo Kim;Kwang-Hun Choi;Dong-Wook W. Ko
    • Korean Journal of Environment and Ecology
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    • v.37 no.2
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    • pp.140-150
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    • 2023
  • The Eurasian otter (Lutra lutra) is an apex predator of the riparian ecosystem. It is a keystone and an indicator species; consequently, its presence suggests a sustainable water environment. Otter is a keystone species as a predator at the top of the food web in the aquatic environment and an indicator species representing the health of the aquatic environment. Although Eurasian otters disappeared from the Han River urban water system because of anthropogenic activities like habitat destruction, poaching, and environmental pollution in the 1980s, the species were sighted in the Cheonggye Stream, Jungrang Stream, and Seongnae Stream, which are urban sections of the Han River, in 2016 and 2021. Therefore, it is pertinent to assess the habitat potential in the area for conservation and management measures to ensure its permanent presence. However, existing studies on otter habitats focused on natural rivers and reservoirs, and there is a limit to applying them to habitats artificially confined habitats in narrow spaces such as tributaries in urban areas of the Han River. This study selected the Cheonggye Stream, an artificially restored urban stream, to evaluate its potential as a habitat for Eurasian otters in urban water environments using the habitat suitability index (HSI). The HSI was calculated with selected environment attributes, such as the cover, food, and threat, that best describe the L. lutra habitat. According to the results, the confluence area of Seongbuk Stream and Cheonggye Stream and the confluence area of Cheonggye Stream and Jungnang Stream were suitable otter habitats, requiring appropriate conservation efforts. The HSI model suggests a valuable method to assess the habitat quality of Eurasian otters in urban water environments. The study is crucial as it can help rehabilitate the species' populations by identifying and managing potential Eurasian otter habitats in highly urbanized areas of the Han River basin and its tributaries.

A Correlation Analysis between Physical Disturbance and Fish Habitat Suitability before and after Channel Structure Rehabilitation (하천구조 개선에 따른 어류 서식적합도와 물리적 교란의 상관분석)

  • Choi, Heung Sik;Lee, Woong Hee
    • Ecology and Resilient Infrastructure
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    • v.2 no.1
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    • pp.33-41
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    • 2015
  • In this study, an optimal improvement method of stream channel structure is presented for the enhancement of fish habitat suitability by genetic algorithm. The correlation between fish habitat suitability and physical disturbance in stream is analyzed according to the changes of hydraulic characteristics by channel structure rehabilitation. Zacco koreanus which is an indicator fish of the soundness of aquatic ecosystem was selected as a restoration target species by investigating the community characteristics of fish fauna and river environments in Wonju stream. The habitat suitability is investigated by PHABSIM with the habitat suitability index of Zacco koreanus. Hydraulic analysis by HEC-RAS and physical disturbance evaluation in stream are carried out. The optimal channel width modified for the enhancement of fish habitat suitability is provided. The correlation analysis between habitat suitability and physical disturbance with the change of hydraulic characteristics by channel modification showed that the proper channel modification enhanced fish habitat suitability and mitigated physical disturbance in the stream. The improvement of physical disturbance score by the channel structure rehabilitation for the enhancement of fish habitat suitability was confirmed in this study.

Application of Habitat Suitability Models for Assessing Climate Change Effects on Fish Distribution (어류 분포에 미치는 기후변화 영향 평가를 위한 서식적합성 모형 적용)

  • Shim, Taeyong;Bae, Eunhye;Jung, Jinho
    • Ecology and Resilient Infrastructure
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    • v.3 no.2
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    • pp.134-142
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    • 2016
  • Temperature increase and precipitation changes caused by change alter aquatic environments including water quantity and quality that eventually affects the habitat of aquatic organisms. Such changes in habitat lead to changes in habitat suitability of the organisms, which eventually determines species distribution. Therefore, conventional habitat suitability models were investigated to evaluate habitat suitability changes of freshwater fish cause by change. Habitat suitability models can be divided into habitat-hydraulic (PHABSIM, CCHE2D, CASiMiR, RHABSIM, RHYHABSIM, and River2D) and habitat-physiologic (CLIMEX) models. Habitat-hydraulic models use hydraulic variables (velocity, depth, substrate) to assess habitat suitability, but lack the ability to evaluate the effect of water quality, including temperature. On the contrary, CLIMEX evaluates the physiological response against climatic variables, but lacks the ability to interpret the effects of physical habitat (hydraulic variables). A new concept of ecological habitat suitability modeling (EHSM) is proposed to overcome such limitations by combining the habitat-hydraulic model (PHABSIM) and the habitat-physiologic model (CLIMEX), which is able to evaluate the effect of more environmental variables than each conventional model. This model is expected to predict fish habitat suitability according to climate change more accurately.

Habitat Analysis Study of Honeybees(Apis mellifera) in Urban Area Using Species Distribution Modeling - Focused on Cheonan - (종분포모형을 이용한 도시 내 양봉꿀벌 서식환경 분석 연구 - 천안시를 중심으로 -)

  • Kim, Whee-Moon;Song, Won-Kyong;Kim, Seoung-Yeal;Hyung, Eun-Jeong;Lee, Seung-Hyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.20 no.3
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    • pp.55-64
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    • 2017
  • The problem of the population number of honeybees that is decreasing not only domestically but also globally, has a great influence on human beings and the entire ecosystem. The habitat of honeybees is recognized to be superior in urban environment rather than rural environment, and predicting for habitat assessment and conservation is necessary. Based on this, we targeted Cheonan City and neighboring administrative areas where the distribution of agricultural areas, urban areas, and forest areas is displayed equally. In order to predict the habitat preferred by honeybees, we apply the Maxent model what based on the presence information of the species. We also selected 10 environmental variables expected to influence honeybees habitat environment through literature survey. As a result of constructing the species distribution model using the Maxent model, 71.7% of the training data were shown on the AUC(Area Under Cover) basis, and it was be confirmed with an area of 20.73% in the whole target area, based on the 50% probability of presence of honeybees. It was confirmed that the contribution of the variable has influence on land covering, distance from the forest, altitude, aspect. Based on this, the possibility of honeybee's habitat characteristics were confirmed to be higher in wetland environment, in agricultural land, close to forest and lower elevation, southeast and west. The prediction of these habitat environments has significance as a lead research that presents the habitat of honeybees with high conservation value of ecosystems in terms of urban space, and it will be useful for future urban park planning and conservation area selection.

Comparison of Sedimentary Environmental Characteristic of Tidal Flats on the West Coast of Korea Depending on the Habitation of Mud Shrimp Upogebia major (서해안 갯벌 쏙(Upogebia major) 서식지와 비 서식지의 퇴적환경 특성)

  • Jeon, Seung Ryul;Hong, SokJin;Choi, Yonghyeon;Cho, Yoon Sik;Song, Jae-Hee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.52 no.6
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    • pp.656-665
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    • 2019
  • Environmental monitoring was conducted to identify the characteristics and patterns of sedimentary environments of tidal flats in 12 areas on the west coast of Korea. The habitat of the mud shrimp Upogebia major contained higher organic and mud contents compared to the habitat of the manila clam Ruditapes philippinarum. In particular, the mud content increased from 84.38% to 89.18% in the Seongam-4 area, where the mud shrimp and manila clam coexist, and the mean grain size exhibited a finer particle size, from 5.48 Φ to 5.80 Φ. In the mud shrimp habitat, the sediment mud content was > 60% and the mean grain size was > 5 Φ. Additionally, the mud shrimp only inhabited open coast tidal flat areas. The management of shellfish aquaculture farms by physical methods should be continued based on comparison of the sedimentary environments in the Boryeong and Seongam areas in response to the damage to the mud shrimp habitat.