• 제목/요약/키워드: Maxent model

검색결과 37건 처리시간 0.022초

Maxent 모델을 이용한 양봉꿀벌의 서울시 수분 잠재환경 분석 (The Analysis of Pollination Potential Environment for Apis mellifera in Seoul Using Maxent Modeling Approach)

  • 김윤호;조용현;배양섭;김다윤
    • 한국환경복원기술학회지
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    • 제23권4호
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    • pp.85-96
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    • 2020
  • The honeybee serves for most entomophilous flowers. They are a core species for maintaining the ecological system. Though the urban ecological system needs bees' mediation of pollination as well, we have little understanding on how the honeybee reacts to the physical environments of an urban city. This study is a basic research to enhance the potential environment for pollination in an urban area and aims to review the urban environmental variables which are highly linked to the pollination mediations by the honeybee. The study composed a Maxent model by adopting nine urban environmental variables and the locations of the Apis mellifera's appearances around 52 spots in Seoul. The variables reflect the ecology of the Apis mellifera. Of the urban environmental variables used for the model composition, six variables were found as not having meaningful correlations with the Apis mellifera's appearances and finally, building coverage, actual vegetation and land cover were selected as the appearance variables of the Apis mellifera. The AUC, the reliability indicator of the final model was 0.791 (sd=0.077). And the importance data of the variables used for the model were 55.6%, 27.9%, and 16.5% for building coverage, actual vegetation and land cover, respectively. The result of the study showed that the building coverage has the highest correlation with the appearance of the honeybee. And, as per the actual vegetation, the artificially tree planted area as well as the cultivated field and meadow in an urban area were functioning as the most important environmental conditions for the honeybee to be inhabitable. The study is expected to be utilized as the base material for the urban planning and park green area planning to enhance the potential environment for pollination in an urban area.

한반도에서 종 분포 모델을 이용한 두 침입외래식물, 돼지풀과 물참새피의 잠재적 분포 예측 (Prediction of Potential Distributions of Two Invasive Alien Plants, Paspalum distichum and Ambrosia artemisiifolia, Using Species Distribution Model in Korean Peninsula)

  • 이승현;조강현;이우주
    • Ecology and Resilient Infrastructure
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    • 제3권3호
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    • pp.189-200
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    • 2016
  • 종분포 모델은 어떤 지역에서 침입외래종이 어떻게 확장되고 어떤 환경 요인이 이들의 분포에 영향을 미치는지를 이해하는데 매우 유용한 도구이다. 본 연구에서는 한반도에서 두 침입외래종인 돼지풀 (Ambrosia artemisiifolia)과 물참새피 (Paspalum distichum)의 분포에 대하여 연구하였다. 이 두 종의 현재의 분포지에서 기후환경 요인을 분석하고 이 두 종의 분포를 예측하기 위하여 Maxent (the maximum entropy) 모델을 이용하였다. 이 두 종의 출현 자료는 Global Biodiversity Information Facility와 우리나라의 식물종 데이터베이스에서, 생물기후 자료는 WorldClim 자료로부터 얻었다. 모델을 수행한 결과, 자생지 위치자료를 이용한 예측 결과보다 전지구 위치자료를 이용한 예측이 연구 대상종의 잠재적 분포지를 잘 설명하였다. 이들 종의 분포에 기여한 기후환경 요인으로서 돼지풀에서는 최건월의 강수량과 연평균온도가, 물참새피에서는 연평균온도와 최한사분기의 평균온도가 선정되었다. Maxent 종분포 모델은 외래종의 침입을 예측하고 이들의 확산을 관리하는데 유용한 도구가 될 것으로 생각된다.

위성영상과 Maxent를 활용한 생태계교란생물 분포지역 예측 : DMZ의 단풍잎돼지풀을 대상으로 (Predicting the Potential Distributions of Invasive Species Using the Landsat Imagery and Maxent : Focused on "Ambrosia trifida L. var. trifida" in Korean Demilitarized Zone)

  • 박현철;임정철;이정환;이관규
    • 한국환경복원기술학회지
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    • 제20권1호
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    • pp.1-12
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    • 2017
  • This study has been carried out for the purpose of predicting the potential habitat sites of invasive alien plants in the DMZ and providing the basic data for decision-making in managing the future DMZ natural environment. From 2007 to 2015, this study collected the data for the advent of Ambrosia trifida var. trifida through fieldwork around the DMZ area, and simulated the potential distribution area of Ambrosia trifida var. trifida using Maxent model among the models of species distributions. As a result, it showed that the potential distribution area of the Ambrosia trifida var. trifida was concentrated in the western DMZ with relatively low altitude and scanty in the central east regions with relatively high elevation and forest cover rate. Because the invasive alien vegetation is a significant threatening factor in the agriculture and restoration of ecology and it costs a lot to restore the area already invaded by invasive alien vegetation, advance precautions are necessary to prevent biological invasions. It is expected that it is possible to predict the disturbed ecosystems through this study for the efficient land use within DMZ in the future and to apply this study in setting up the areas for the development and conservation within the DMZ.

Maxent 모델을 이용한 호박벌과 양봉꿀벌의 수분 잠재환경 비교 분석 - 서울시를 중심으로 - (A Comparative Analysis on the Pollination Potential Environment of Apis millifera and Bombus ignitus Using the Maxent Model - Focused on Seoul -)

  • 김윤호;조용현;배양섭;김태종;손인기
    • 한국환경복원기술학회지
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    • 제24권1호
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    • pp.25-36
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    • 2021
  • The honey bee has a crucial ecological status for maintaining the natural ecology system. Pollination mediations by honey bees are recognized as an efficient way to enhance the quality of biological diversity and green areas in the nature and the urban ecological system. However, the population of bee around the world is decreasing and we do not know exactly how bees react to the physical environment in the urban area. This study is a basic research for the improvement of pollination services in the Korean urban ecological system. It aims to induce and review environmental variables which have high relations with the activities of pollination mediation insects in the urban area. The study established a Maxent model using five urban environmental variables that reflect the ecology of Bombus ignitus and the place information where Bombus ignitus appears in 18 spots of Seoul city, and compared with previous research results on Apis millifera. Bombus ignitus preferred places with more natural environments such as mountain forest areas and vicinities of streams. They preferred Stratified Tree Area the most among the vegetation types existing in the urban area. Comparing chicken models, both species saw their response value drop as the building coverage rose. In the case of Apis millifera and Bombus ignitus variables, the response value of both species was high in 10 out of 20 types. The result of this study is expected to provide basic information for improving the pollination services in the Korean urban area and to be utilized as the basic materials for the future urban planning.

종분포모형의 불확실성 확인을 위한 앙상블모형 적용 (Applying Ensemble Model for Identifying Uncertainty in the Species Distribution Models)

  • 권혁수
    • 대한공간정보학회지
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    • 제22권4호
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    • pp.47-52
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    • 2014
  • 종분포모형은 생물다양성 평가, 보호지역 지정, 서식지 관리 및 복원, 기후변화 예측 등의 다양한 분야에 활용되고 있으나 공공이나 정책분야에서는 모형의 불확실성으로 인하여 활용이 제한적이었다. 최근에는 이러한 모형의 불확실성을 저감하기 위하여 앙상블이나 합의모형 등의 다중모형을 적용하는 연구가 증가하고 있다. 이에 본 연구에서는 히어리를 대상으로 단일모형과 앙상블(다중) 모형을 적용하고 이를 비교하는 연구를 수행하였다. 모형은 AUC와 kappa, TSS를 이용하여 적합도를 평가하였으며, 이 중 모형 간의 비교가 용이하고 이항형 지도로 바로 변환할 수 있는 TSS가 효과적이었다. 단일모형과 앙상블 모형 모두 높은 모형적합도를 나타내었으며, 다중 모형 중에서는 RF, Maxent, GBM이 높게, GAM, SRE는 비교적 낮게 평가되었다. 예측지도에서는 단일모형에 비해 다중모형의 예측범위가 과대 추정되는 경향이 있었다. 이는 여러 모형이 중첩된 결과로 현장전문가와 모형전문가들 간의 협력연구를 통하여 적절한 모형 선택과 가중치 부여 등을 통하여 문제를 해결할 수 있다. 앙상블모형을 공간의사결정이나 보호지역계획에 활용하기 위해서는 불확실성의 정도와 원인을 파악하고, 이를 저감하려는 개선작업과 함께 결과의 불확실성이나 위험성을 인지하고 의사결정을 해야 한다.

야생동물 서식지 잠재력과 공간가치분류를 통한 정책방향 설정 (Policy Decision Making Through Wildlife Habitat Potential With Space Value Categorization)

  • 장래익;이명우
    • 한국환경복원기술학회지
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    • 제18권1호
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    • pp.1-12
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    • 2015
  • Beginning of the human ecology in 1920s, the efforts for applying the environmental values to a policy have been embodied by the enactments of international agreement and relevant laws. The government has been struggling to adopt the environmental values for the policy by enacting the relevant laws and establishing the environmental value evaluation information (environmental conservation value assessment map, eco-natural map, biotope map). In spite of the efforts to apply the environmental value assessment information for the habitat potential of wildlife, the application is being challenged by the discrepancy in methods and criteria. Thus this study intends to measure the potential of wildlife habitat and apply it to the spatial value classification for the application plan of wildlife habitat potential in policy. Maxent was used for the habitat potential and the land types were classified depending on the surface and land use pattern of cadastral map. As a result, the policy matrix including conservation strategy(CS), restoration strategy(RS), practical use strategy(PS) and development strategy(DS) has been deduced as CS $13.05km^2$(2.38%), RS $1.64km^2$(0.30%), PS $162.42km^2$(29.57%) and DS $8.56km^2$(1.56%). CS was emerged mostly on forest valleys and farmlands, and RS was appeared in the road area near the conservation strategy areas. Boryung downtown and Daecheon Beach were the center of DS, while the forest and farmlands were presented as PS. It is significant that this study suggest the new approaching method by comparing the wildlife habitat potential with the land type. Since this study evaluated the environmental value by one species of leopard cat (Prionailurusbengalensis) with Maxent model, it is necessary to apply the habitat potential measuring method for various target species as further research.

기후변화에 의한 눈잣나무의 서식지 분포 예측 (Predicting the suitable habitat of the Pinus pumila under climate change)

  • 박현철;이정환;이관규
    • 환경영향평가
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    • 제23권5호
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    • pp.379-392
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    • 2014
  • 이 연구는 국립생물자원에서 선정한 기후변화생물지표 중에서 남한의 설악산에 제한적으로 분포하는 눈잣나무의 기후변화에 의한 잠재 서식지 예측을 위해 시행되었다. 눈잣나무의 잠재서식지 예측을위해 IPCC(AR5)의 대표농도경로(RCP)를 기후변화 시나리오로 사용하였다. 종 분포 모형은 Maxent를 사용하였고, 환경변수는 고도, 연평균기온 등으로 총 8개이다. 남한이 눈잣나무 분포지역은 설악산이 유일한 지역으로 지리적 범위는 위도 $38^{\circ}7^{\prime}8^{{\prime}{\prime}}N{\sim}38^{\circ}7^{\prime}14^{{\prime}{\prime}}N$ 경도 $128^{\circ}28^{\prime}2^{{\prime}{\prime}}E{\sim}128^{\circ}27^{\prime}38^{{\prime}{\prime}}E$ 범위에 국지적으로 분포하며, 고도는 1,586m~1,688m 범위에 분포한다. 종 분포 모형의 모형 정확도는 0.978으로 매우 우수하였고 잠재서식지 예측에 기여도가 높은 환경변수는 고도로 나타났다. LPT를 기준으로 선정된 현재기후의 잠재 서식지는 $7,345km^2$이며 기후변화 시나리오를 적용한 미래의 잠재 서식지 면적은 감소하였고 감소폭은 RCP 4.5보다 RCP 8.5가 많았다. 설악산의 눈잣나무 개체군 분포 지역은 한반도의 남방 한계선으로 예상되며 기후변화에 의해 개체군의 축소 및 소실이 예상되므로 전략적인 유전자원 확보를 위한 대책이 필요하다.

Consequences of land use change on bird distribution at Sakaerat Environmental Research Station

  • Trisurat, Yongyut;Duengkae, Prateep
    • Journal of Ecology and Environment
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    • 제34권2호
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    • pp.203-214
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    • 2011
  • The objectives of this research were to predict land-use/land-cover change at the Sakaerat Environmental Research Station (SERS) and to analyze its consequences on the distribution for Black-crested Bulbul (Pycnonotus melanicterus), which is a popular species for bird-watching activity. The Dyna-CLUE model was used to determine land-use allocation between 2008 and 2020 under two scenarios. Trend scenario was a continuation of recent land-use change (2002-2008), while the integrated land-use management scenario aimed to protect 45% of study area under intact forest, rehabilitated forest and reforestation for renewable energy. The maximum entropy model (Maxent), Geographic Information System (GIS) and FRAGSTATS package were used to predict bird occurrence and assess landscape fragmentation indices, respectively. The results revealed that parts of secondary growth, agriculture areas and dry dipterocarp forest close to road networks would be converted to other land use classes, especially eucalyptus plantation. Distance to dry evergreen forest, distance to secondary growth and distance to road were important factors for Black-crested Bulbul distribution because this species prefers to inhabit ecotones between dense forest and open woodland. The predicted for occurrence of Black-crested Bulbul in 2008 covers an area of 3,802 ha and relatively reduces to 3,342 ha in 2020 for trend scenario and to 3,627 ha for integrated-land use management scenario. However, intact habitats would be severely fragmented, which can be noticed by total habitat area, largest patch index and total core area indices, especially under the trend scenario. These consequences are likely to diminish the recreation and education values of the SERS to the public.

Projecting suitable habitats considering locational characteristics of major wild vegetables and climate change impacts

  • Choi, Jaeyong;Lee, Sanghyuk
    • 농업과학연구
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    • 제46권3호
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    • pp.661-670
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    • 2019
  • In this study, we constructed a model of an area where the production and production amount of wild vegetables which are designated as short term income forest products for the whole country are self-sufficient for the representative Eastern Braken fern(Pteridium aquilinum)and Edible aster(Aster scaber). The difference between the existing cultivation site and the model result was examined, and the distribution of the cultivable area was simulated according to the near future climate change by the 2050s. The degree of agreement between the cultivated area and the actual native area was very low at 14.5% for Eastern Braken fern and 12.9% for Edible aster. Using the Maxent model, which has already been proven by many research examples, the cultivation maps through the model can guarantee statistical accuracy by considering many variables. To analyze future location changes, the RCP 4.5 scenario and the RCP 8.5 scenario were applie Edible aster d to predict potential future cultivable areas and compare them to the present. There was no decrease in the cultivable area due to climate change nationwide. However, in the RCP 8.5 scenario for Eastern Braken fern and the RCP 4.5 scenario for Edible aster, declining areas such as Gangwon-do, Jeollabuk-do and Gyeongsangbuk-do showed prominence according to the scenarios. The result of this study suggests that various models can be used for the production of short-term forest productivity maps and it will be used as a climate change impact assessment data for competitive forest products considering the influence of future climate change.

New record of a blood-feeding terrestrial leech, Haemadipsa rjukjuana Oka, 1910 (Haemadipsidae, Arhynchobdellida) on Heuksando Island and possible habitat estimation in the current and future Korean Peninsula using a Maxent model

  • Tae-Yeong Eom;Hyeon-Soo Kim;Yeong-Seok Jo
    • Journal of Species Research
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    • 제12권1호
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    • pp.109-113
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    • 2023
  • To build a distribution model for Haemadipsa rjukjuana, we collected current occurrences of the species on Heuksando with adjacent islands. Based on current locations and 19 climate variables with DEM (digital elevation model), we built the MaxEnt (maximum entropy) species distribution model for H. rjukjuana in the islands. Then, we applied the MaxEnt model to the mainland of Korea with the current climate condition and topology. In addition to the current distribution scenario, we predicted the future distribution scenarios in Korea by Coupled Model Intercomparison Project Phase 6 (CMIP6) global climate models. Shared Socioeconomic Pathway (SSP) 585 of two CMIP6 models(GISS-E2-1 and INM-CM4-8) from 2040 to 2100 were used for the future projection.