• Title/Summary/Keyword: Species distribution models

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Habitat Prediction and Impact Assessment of Eurya japonica Thunb. under Climate Change in Korea (기후변화에 따른 한반도 사스레피나무의 생육지 예측과 영향 평가)

  • Yun, Jong-Hak;Park, Jeong Soo;Choi, Jong-Yun;Nakao, Katsuhiro
    • Journal of Environmental Impact Assessment
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    • v.26 no.5
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    • pp.291-302
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    • 2017
  • The research was carried out in order to find climate factors which determine the distribution of Eurya japonica, and the potential habitats (PHs) under the current climate and climate change scenario by using species distribution models (SDMs). Four climate factors; the warmth index (WI), the minimum temperature of the coldest month (TMC), summer precipitation (PRS), and winter precipitaion (PRW) : were used as independent variables for the model. Seventeen general circulation models under RCP (Representative concentration pathway) 8.5 scenarios were used as future climate scenarios for the 2050s (2040~2069) and 2080s (2070~2099). Highly accurate SDMs were obtained for E. japonica. The model of distribution for E. japonica constructed by SDMs showed that minimum temperature of the coldest month (TMC) is a major climate factor in determining the distribution of E. japonica. The area above the $-5.7^{\circ}C$ of TMC revealed high occurrence probability of the E. japonica. Future PHs for E. japonica were projected to increase respectively by 2.5 times, 3.4 times of current PHs under 2050s and 2080s. It is expected that the potential of E. japonica habitats is expanded gradually. E. japonica is applicable as indicator species for monitoring in the Korean Peninsula. E. japonica is necessary to be monitored of potential habitats.

Using High Resolution Ecological Niche Models to Assess the Conservation Status of Dipterocarpus lamellatus and Dipterocarpus ochraceus in Sabah, Malaysia

  • Maycock, Colin R.;Khoo, Eyen;Kettle, Chris J.;Pereira, Joan T.;Sugau, John B.;Nilus, Reuben;Jumian, Jeisin;Burslem, David F.R.P.
    • Journal of Forest and Environmental Science
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    • v.28 no.3
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    • pp.158-169
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    • 2012
  • Sabah has experienced a rapid decline in the extent of forest cover. The precise impact of habitat loss on the conservation status of the plants of Sabah is uncertain. In this study we use the niche modelling algorithm MAXENT to construct preliminary, revised and final ecological niche models for Dipterocarpus lamellatus and Dipterocarpus ochraceus and combined these models with data on current land-use to derive conservation assessments for each species. Preliminary models were based on herbarium data alone. Ground surveys were conducted to evaluate the performance of these preliminary models, and a revised niche model was generated from the combined herbarium and ground survey data. The final model was obtained by constraining the predictions of the revised models by filters. The range overlap between the preliminary and revised models was 0.47 for D. lamellatus and 0.39 for D. ochraceus, suggesting poor agreement between them. There was substantial variation in estimates of habitat loss for D. ochraceus, among the preliminary, revised and constrained models, and this has the potential to lead to incorrect threat assessments. From these estimates of habitat loss, the historic distribution and estimates of population size we determine that both species should be classified as Critically Endangered under IUCN Red List guidelines. Our results suggest that ground-truthing of ecological niche models is essential, especially if the models are being used for conservation decision making.

Distribution Patterns and Ecological Characters of Paulownia coreana and P. tomentosa in Busan Metropolitan City Using MaxEnt Model (MaxEnt 모형을 활용한 부산광역시 내 오동나무 및 참오동나무의 분포 경향과 생태적 특성)

  • Lee, Chang-Woo;Lee, Cheol-Ho;Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.2
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    • pp.87-97
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    • 2017
  • Paulownia species has long been recognized in Korean traditional culture and the values of the species have been researched in various focuses. However, studies on distribution and ecological characteristics of the species are still needed. This study aimed to identify distribution trends and ecological characteristics of two Paulownia species in Busan metropolitan city using the MaxEnt model. The MaxEnt model was established based on the environmental factors such as positioning information of the Paulownia species, topography, climate and degree of anthropogenic disturbance potentiality (ADP), which was collected in the on-site research. The study verified that the accuracy of the model was appropriate as the AUC value of Paulownia coreana and P. tomentosa was 0.809, respectively. In terms of the distribution trends of the two Paulownia species in the research area depending on the distribution model, they were both mainly distributed in downtown where built-up area and bare ground were densely concentrated. The potential distribution area of the two species was identified as $137.4km^2$ for P. coreana and $135.0km^2$ for P. tomentosa. The distribution probability was high in Jung-gu, Dongrae-gu, Busanjin-gu and Yeonje-gu. As a result of the analysis on contribution of the environmental factors, it was turned out that the degree of anthropogenic disturbance potentiality (ADP) contributed to distribution of P. coreana and P. tomentosa by about 50%, and the contribution of the environmental factors had a positive correlation with the degree of ADP. The elevation had a negative correlation with both the two species, which was considered because the species must compete more with native species in natural habitats as the altitude above sea level rises. The research findings demonstrated numerically that the distribution of P.coreana and P. tomentosa depended on artificial activities, and indicated the relevance with the Korean traditional landscape. These findings are expected to provide meaningful information in using, preserving and restoring Paulownia species.

Assessing the Climatic Suitability for the Drywood Termite, Cryptotermes domesticus Haviland (Blattodea: Kalotermitidae), in South Korea (마른나무흰개미(가칭)의 국내 기후적합성 평가)

  • Min-Jung Kim;Jun-Gi Lee;Youngwoo Nam ;Yonghwan Park
    • Korean journal of applied entomology
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    • v.62 no.3
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    • pp.215-220
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    • 2023
  • A recent discovery of drywood termites (Cryptotermes domesticus) in a residential facility in Seoul has raised significant concern. This exotic insect species, which can damage timber and wooden buildings, necessitates an immediate investigation of potential infestation. In this study, we assessed the climatic suitability for this termite species using a species distribution modeling approach. Global distribution data and bioclimatic variables were compiled from published sources, and predictive models for climatic suitability were developed using four modeling algorithms. An ensemble prediction was made based on the mean occurrence probability derived from the individual models. The final model suggested that this species could potentially establish itself in tropical coastal regions. While the climatic suitability in South Korea was generally found to be low, a careful investigation is still warranted due to the potential risk of colonization and establishment of this species.

A nationwide analysis of mammalian biodiversity hotspots in South Korea (전국단위의 포유류 생물다양성우수지역 분석 연구)

  • Kim, Jiyeon;Kwon, Hyuksoo;Seo, Changwan;Kim, Myungjin
    • Journal of Environmental Impact Assessment
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    • v.23 no.6
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    • pp.453-465
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    • 2014
  • Hotspots are top sites in terms of species diversity as the most threatened and most diverse sites which have been used to select priority areas for reserves. The purpose of this paper is to identify biodiversity hotspots through analyzing nationwide spatial patterns of species richness and rarity of Korean mammals. Four endangered mammals and eleven common mammals were selected as target species. Environmental variables as model input data were consisted of topography, distance, and vegetation structure etc. and Maxent was used to develop species distribution models for target species. Species richness and rarity were used as index of biodiversity. The results of this study were as follows. Firstly, hotspots of species richness for endangered mammals were in high elevation and steep mountain areas. However, species richness for whole mammals were high in low elevation of mountains. Secondly, distribution pattern of species rarity for endangered mammals were similar as richness. However, hotspots of species rarity for whole mammals were a little different from species richness. Species rarity was high in both low and high elevation of mountain areas. This study will provide the useful information for a biodiversity assessment, a habitat conservation, a national ecological network plan, and the management of protected areas.

The Planting Models of Carpinus turczaninowii Community by the Plant Community Structure Analysis in Badahyanggi Arboretum - Case Study of Daebu-Yeongheung Islands - (군집구조분석을 통한 바다향기수목원 소사나무림 식재모델 연구 - 대부도 및 영흥도를 대상으로 -)

  • Kim, Yong-Hoon;Kwon, Oh-Jung;Ban, Su-Hong;Oh, Choong-Hyeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.4
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    • pp.31-45
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    • 2020
  • This study suggested the planting models of Carpinus turczaninowii community to make in Badahyanggi Arboretum and was carried out to the structure of C. turczaninowii commnity in Daebu-Yeongheung Islands. In order to identify the current ecological environment, this study set to 13 plots(i.e. 100㎡) for analysing detailed structure of plant communities. The research methodology was qualitative analysis. It used TWINSPAN, PCA and Indicator Species Analysis tools which are performed well in several comparisons of classification techniques and one of the ordination techniques showed that the plant communities. The results were classified into 3 communities that C. turczaninowii-Pinus densiflora community(I), C. turczaninowii-Quercus serrata community(II) and C. turczaninowii-Platycarya strobilacea community(III). In all of communities, C. turczaninowii was dominant species in canopy layer and understory layer, the degree of closure was high. Proposed the planting models that are I~II communities based on planting status in Badahyanggi Arboretum(Island Plant Botanical Garden), the structure of plant communities, indicator species and individual distribution by DBH classes. Also, The multi-layer planting plans are necessary, such as P. strobilacea, Lindera erythrocarpa, Viburnum carlesii, V. dilatatum, Ligustrum obtusifolium, Zanthoxylum schinifolium and so on.

Estimation of Fish Species Diversity of Small and Medium Rivers of Korea with Fish Species-Habitat Relationship Models od GAP (GAP기법을 이용한 종소하천의 어류종다양성 예측기법 연구)

  • 박종화;홍성학
    • Spatial Information Research
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    • v.6 no.1
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    • pp.91-102
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    • 1998
  • The objectives of this research were to develop fish-habitat relationship models which can be used to estimate fish species riclmess of small and medium rivers in Korea, and test the accuracy of the models. The models are based on the Aquatic GAP Analysis model in the New York Cooperative Fish & Wildlife Research Unit (19%), and they employ three habitat factors; river size, physical habitat, and water quality of each river segment. Model 1 and model II are based on the water quality standard for life support of EP A and the water quality class of Korea, respectively. Test sites for this study include one urban stream and three less spoiled tributaries of the Han River. The results of this research can be summarized as follows. First, the number of habitat types identified by model I and model II are nine and 14, respectively. Second, the average accuracy of the three distribution maps of rare or endangered fish species are 80.6% (model 1) and 81.2% (model II). Third, the accuracy of fish species richness are 94% (model 1) and 95% (model II), and the water quality is the most important factor affecting fish species richness. Fourth, the accuracy of fish species list are 50.5% (model 1) and 68.7% (model II), but the accuracy of less spoiled stream segments and that of polluted stream segments are 67.1% and 86.5%, respectively. Finally, it can be concluded that the overall performance of model II is better than that of model I at our test sites.

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Potential impact of climate change on the species richness of subalpine plant species in the mountain national parks of South Korea

  • Adhikari, Pradeep;Shin, Man-Seok;Jeon, Ja-Young;Kim, Hyun Woo;Hong, Seungbum;Seo, Changwan
    • Journal of Ecology and Environment
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    • v.42 no.4
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    • pp.298-307
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    • 2018
  • Background: Subalpine ecosystems at high altitudes and latitudes are particularly sensitive to climate change. In South Korea, the prediction of the species richness of subalpine plant species under future climate change is not well studied. Thus, this study aims to assess the potential impact of climate change on species richness of subalpine plant species (14 species) in the 17 mountain national parks (MNPs) of South Korea under climate change scenarios' representative concentration pathways (RCP) 4.5 and RCP 8.5 using maximum entropy (MaxEnt) and Migclim for the years 2050 and 2070. Results: Altogether, 723 species occurrence points of 14 species and six selected variables were used in modeling. The models developed for all species showed excellent performance (AUC > 0.89 and TSS > 0.70). The results predicted a significant loss of species richness in all MNPs. Under RCP 4.5, the range of reduction was predicted to be 15.38-94.02% by 2050 and 21.42-96.64% by 2070. Similarly, under RCP 8.5, it will decline 15.38-97.9% by 2050 and 23.07-100% by 2070. The reduction was relatively high in the MNPs located in the central regions (Songnisan and Gyeryongsan), eastern region (Juwangsan), and southern regions (Mudeungsan, Wolchulsan, Hallasan, and Jirisan) compared to the northern and northeastern regions (Odaesan, Seoraksan, Chiaksan, and Taebaeksan). Conclusions: This result indicates that the MNPs at low altitudes and latitudes have a large effect on the climate change in subalpine plant species. This study suggested that subalpine species are highly threatened due to climate change and that immediate actions are required to conserve subalpine species and to minimize the effect of climate change.

Mapping Species-Specific Optimal Plantation Sites Based on Environmental Variables in Namwon City, Korea (환경요인을 이용한 남원시의 적지적수도 제작)

  • Moon, Ga Hyun;Kim, Yong Suk;Lim, Joo Hoon;Shin, Man Yong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.2
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    • pp.126-135
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    • 2015
  • This study was conducted to develop a large scale map of species-specific plantation sites based on selected environmental variables such as topography, soil, and climatic factors in Namwon city. Site index equations by tree species were first regressed to 27 environmental variables that could influence the productivity of forest sites using digital forest site maps, digital climate maps, and the 5th National Forest Inventory data. Site index equations by tree species were all evaluated to estimate site productivity using 4-5 environmental variables, and the models' reliability was confirmed based on evaluation statistics. The determination coefficients of site index equations by species ranged from 0.42 to 0.76. With the site index equations, the site conditions appropriate for productive sites by species were considered to assess spatial distribution of productive areas for each species. The final map for optimal plantation in Namwon city was produced based on both site index equations and site conditions appropriate for productive sites by each species using GIS technique. Field survey was conducted to evaluate the suitability of selected species on the map of species-specific plantation sites. Results showed that the plantation map provides relatively reasonable spatial distribution of productive areas for selected species. It was revealed, however, that the sites evaluated as 'not suitable' for any tree species should be revised and complemented with additional information, especially with the site conditions appropriate for productive sites by species of interest. The outcomes of this study are expected to provide information for making customized species-specific plantation maps.

Prediction of Species Distribution Changes for Key Fish Species in Fishing Activity Protected Areas in Korea (국내 어업활동보호구역 주요 어종의 종분포 변화 예측)

  • Hyeong Ju Seok;Chang Hun Lee;Choul-Hee Hwang;Young Ryun Kim;Daesun Kim;Moon Suk Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.802-811
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    • 2023
  • Marine spatial planning (MSP) is a crucial element for rational allocation and sustainable use of marine areas. Particularly, Fishing Activity Protected Areas constitute essential zones accounting for 45.6% designated for sustainable fishing activities. However, the current assessment of these zones does not adequately consider future demands and potential values, necessitating appropriate evaluation methods and predictive tools for long-term planning. In this study, we selected key fish species (Scomber japonicus, Trichiurus lepturus, Engraulis japonicus, and Larimichthys polyactis) within the Fishing Activity Protected Area to predict their distribution and compare it with the current designated zones for evaluating the ability of the prediction tool. Employing the Intergovernmental Panel on Climate Change (IPCC) 6th Assessment Report scenarios (SSP1-2.6 and SSP5-8.5), we used species distribution models (such as MaxEnt) to assess the movement and distribution changes of these species owing to future variations. The results indicated a 30-50% increase in the distribution area of S. japonicus, T. lepturus, and L. polyactis, whereas the distribution area of E. japonicus decreased by approximately 6-11%. Based on these results, a species richness map for the four key species was created. Within the marine spatial planning boundaries, the overlap between areas rated "high" in species richness and the Fishing Activity Protected Area was approximately 15%, increasing to 21% under the RCP 2.6 scenario and 34% under the RCP 8.5 scenario. These findings can serve as scientific evidence for future evaluations of use zones or changes in reserve areas. The current and predicted distributions of species owing to climate change can address the limitations of current use zone evaluations and contribute to the development of plans for sustainable and beneficial use of marine resources.