• 제목/요약/키워드: habitat shift

검색결과 28건 처리시간 0.019초

Estimating potential range shift of some wild bees in response to climate change scenarios in northwestern regions of Iran

  • Rahimi, Ehsan;Barghjelveh, Shahindokht;Dong, Pinliang
    • Journal of Ecology and Environment
    • /
    • 제45권3호
    • /
    • pp.130-142
    • /
    • 2021
  • Background: Climate change is occurring rapidly around the world, and is predicted to have a large impact on biodiversity. Various studies have shown that climate change can alter the geographical distribution of wild bees. As climate change affects the species distribution and causes range shift, the degree of range shift and the quality of the habitats are becoming more important for securing the species diversity. In addition, those pollinator insects are contributing not only to shaping the natural ecosystem but also to increased crop production. The distributional and habitat quality changes of wild bees are of utmost importance in the climate change era. This study aims to investigate the impact of climate change on distributional and habitat quality changes of five wild bees in northwestern regions of Iran under two representative concentration pathway scenarios (RCP 4.5 and RCP 8.5). We used species distribution models to predict the potential range shift of these species in the year 2070. Result: The effects of climate change on different species are different, and the increase in temperature mainly expands the distribution ranges of wild bees, except for one species that is estimated to have a reduced potential range. Therefore, the increase in temperature would force wild bees to shift to higher latitudes. There was also significant uncertainty in the use of different models and the number of environmental layers employed in the modeling of habitat suitability. Conclusion: The increase in temperature caused the expansion of species distribution and wider areas would be available to the studied species in the future. However, not all of this possible range may include high-quality habitats, and wild bees may limit their niche to suitable habitats. On the other hand, the movement of species to higher latitudes will cause a mismatch between farms and suitable areas for wild bees, and as a result, farmers will face a shortage of pollination from wild bees. We suggest that farmers in these areas be aware of the effects of climate change on agricultural production and consider the use of managed bees in the future.

The mechanisms leading to ontogenetic diet shift in a microcanivore, Pterogobius elapoides(Gobiidae)

  • Choi, Seung-Ho;Suk, Ho-Young
    • Animal cells and systems
    • /
    • 제16권4호
    • /
    • pp.343-349
    • /
    • 2012
  • A variety of fish species undergo an ontogenetic change in prey selectivity, and several potentially interacting factors, including nutrient requirement, microhabitat change, and foraging ability, may account for the occurrence of the shift. Here we examine the foraging ecology and ontogenetic diet shift of a micro-carnivorous goby, Pterogobius elapoides (serpentine goby), dominant component of fish assemblage in shallow rocky areas off the coast in Korea and Japan. Although most other gobies are primarily benthic carnivores, P. elapoides is a semipelagic fish; however, little is known about how those species change their foraging tactics with growth. In our diet analyses, the most common diet was pelagic copepods and benthic amphipods, and diet shift was observed from pelagic to benthic with growth. The ontogenetic diet shift seems to be the result of the preference for energetically more profitable prey in larger-size classes as well as the results of different prey availability due to among-habitat variation in diet. However, differential food preference does not appear to affect individual scope for searching food. Several factors such as predation pressures and interspecific resource partitioning might contribute to the changes in diet observed among size classes, which were included in our ongoing tests.

법정보호종, 흰발농게(Austruca lactea) 서식 개체수 추정에 대한 검토와 대안 (Considerations and Alternative Approaches to the Estimation of Local Abundance of Legally Protected Species, the Fiddler Crab, Austruca lactea)

  • 유재원;김창수;박미라;정수영;이채린;김성태;안동식;이창근;한동욱;백용해;박영철
    • 한국습지학회지
    • /
    • 제23권2호
    • /
    • pp.122-132
    • /
    • 2021
  • 본 연구에서는 우리나라의 갯벌에서 조사대상으로 삼는 멸종위기야생생물이자 해양보호생물, 흰발농게(Austruca lactea)의 전체 개체수 추정 방법을 검토하였다. 일반적으로 무한모집단에 대한 전수조사는 불가능하며 이는 갯벌 내 제한된 서식처에서 개체수를 추정하더라도 마찬가지이다. 표본으로부터 추정되는 서식 밀도 역시 다양한 생물학적, 생태학적 요인들로 인해 높은 변동성을 보인다. 서식처 경계와 면적은 측정 오차뿐만 아니라 생물의 주기성이나 리듬 활동(주야, 간만 주기 등)에 따라서도 달라진다. 따라서 밀도와 서식처 면적으로 산출되는 전체 개체수는 일시적인 것으로 간주되어야 한다. 이 같은 추정은 인천 송도 갯벌에서 3년 간 관찰된 흰발농게(A. lactea)의 평균 밀도와 표준오차 범위 그리고 공간분포의 시공간적 변동성에 근거하면 타당한 것으로 볼 수 있었다. 본 연구에서는 로지스틱 회귀모형의 출현 확률인 50%를 기준으로, 서식처 보존 가치의 중요성을 반영하는 잠재적 서식처 면적을 전체 개체수 추정의 대안으로 제시하였다. 보편성을 갖춘 모형으로부터 예측되는 잠재적 서식처는 대상종의 주요 환경조건이 급격하게 변하지 않는다면 시간에 따라 일정한 모습을 유지할 것이다. 특정종을 대상으로 개발되는 모형은 추후 서식처 복원/조성 사업에서도 원하는 생물의 정착을 유도하는데도 활용이 가능할 것으로 기대된다.

Vertical Urban Design and Thinking within the Framework of Urban Regeneration

  • Jun Zha;Xuewei Chen;Yan Li
    • 국제초고층학회논문집
    • /
    • 제12권1호
    • /
    • pp.75-82
    • /
    • 2023
  • By limiting population and land resources, a high-density urban form has become the inevitable choice for central cities in the rapid growth of many large cities in China. Due to the shift in urban growth and focus, high-density urban areas require restoration and improvement. This study intends to combine ancient and new districts, establish strategies for enhancing urban function, spatial utility, industry, and transportation, and thus enhance regional holistic effectiveness, by performing in-depth research.

Tree species migration to north and expansion in their habitat under future climate: an analysis of eight tree species Khyber Pakhtunkhwa, Pakistan

  • Muhammad Abdullah Durrani;Rohma Raza;Muhammad Shakil;Shakeel Sabir;Muhammad Danish
    • Journal of Ecology and Environment
    • /
    • 제48권1호
    • /
    • pp.96-109
    • /
    • 2024
  • Background: Khyber Pakhtunkhwa government initiated the Billion Tree Tsunami Afforestation Project including regeneration and afforestation approaches. An effort was made to assess the distribution characteristics of afforested species under present and future climatic scenarios using ecological niche modelling. For sustainable forest management, landscape ecology can play a significant role. A significant change in the potential distribution of tree species is expected globally with changing climate. Ecological niche modeling provides the valuable information about the current and future distribution of species that can play crucial role in deciding the potential sites for afforestation which can be used by government institutes for afforestation programs. In this context, the potential distribution of 8 tree species, Cedrus deodara, Dalbergia sissoo, Juglans regia, Pinus wallichiana, Eucalyptus camaldulensis, Senegalia modesta, Populus ciliata, and Vachellia nilotica was modeled. Results: Maxent species distribution model was used to predict current and future distribution of tree species using bioclimatic variables along with soil type and elevation. Future climate scenarios, shared socio-economic pathways (SSP)2-4.5 and SSP5-8.5 were considered for the years 2041-2060 and 2081-2100. The model predicted high risk of decreasing potential distribution under SSP2-4.5 and SSP5-8.5 climate change scenarios for years 2041-2060 and 2081-2100, respectively. Recent afforestation conservation sites of these 8 tree species do not fall within their predicted potential habitat for SSP2-4.5 and SSP5-8.5 climate scenarios. Conclusions: Each tree species responded independently in terms of its potential habitat to future climatic conditions. Cedrus deodara and P. ciliata are predicted to migrate to higher altitude towards north in present and future climate scenarios. Habitat of D. sissoo, P. wallichiana, J. regia, and V. nilotica is practiced to be declined in future climate scenarios. Eucalyptus camaldulensis is expected to be expanded its suitability area in future with eastward shift. Senegalia modesta habitat increased in the middle of the century but decreased afterwards in later half of the century. The changing and shifting forests create challenges for sustainable landscapes. Therefore, the study is an attempt to provide management tools for monitoring the climate change-driven shifting of forest landscapes.

Recovery, growth and development of Macroorchis spinulosus in albino rats

  • Woo, Ho-Chun;Chai, Jong-Yil;Hong, Sung-Jong
    • Parasites, Hosts and Diseases
    • /
    • 제41권1호
    • /
    • pp.27-33
    • /
    • 2003
  • The developmental features, growth and organogenesis of Macroorchis spinuiosus were observed in albino rats. Globular and thick walled metacercariae, possessed a stylet, Y-shaped excretory bladder and extracecal testes. Un albino rats, M. spinulosus showed habitat shifting. The majority of M. spinulosus reside in the jejunum for the first four days post Infection (p.i.) and migrate to the duodenum at the later stage of infection. M. spinulosus grew rapidly during the first four days and reached full maturity at 14 days p.i. and later reduced in size. The ovary was separated from the genital primodium at one day p.i. The seminal vesicle appeared on the third day and divided into two sacs on the fourth day p.i. and intrauterine eggs and sperm mass were produced on the fourth day. Organogenesis and enlargement of reproductive organs governed the growth of M. spinulosus. The similarity of related species of the genus Macroorchis to M. spinulosus was discussed In consideration to developmental features.

광양만 주둥치(Leiognathus nuchalis)의 서식처 이동에 의한 먹이원 변동 파악을 위한 안정동위원소 분석기법 적용 (Isotopic Evidence for Ontogenetic Shift in Food Resource Utilization during the Migration of the Slipmouth Leiognathus nuchalis in Gwangyang Bay, Korea)

  • 최보형;조현빈;박기연;곽인실
    • 한국어류학회지
    • /
    • 제32권2호
    • /
    • pp.84-90
    • /
    • 2020
  • 섬진강 하구와 광양만에 서식하는 주둥치의 서식처 및 섭식 특성을 비교하기 위해 탄소 및 질소 안정동위원소 분석을 실시하였다. 주둥치의 탄소안정동위원소비(δ13C) 값은 염분이 30 psu보다 낮은 섬진강 하구에서 채집된 개체에서 광양만에 비해 낮은 값이 나타났으며, 이는 섬진강 하구에서 채집된 주둥치가 해당 정점에서 섭식활동을 하고 있음을 의미한다. 이와 대조적으로, 채집된 주둥치의 질소안정동위원소비 (δ15N) 값은 정점 간 큰 차이를 나타내지 않아, 이들이 각 서식처에서 유사한 영양위치를 점유하고 있다는 것을 나타내었다. 주둥치는 만 전체에 널리 분포하고 있어 광염성 어류의 특성을 잘 대변하는 것을 보였는데, 상대적으로 소형개체들이 하구역에서 채집되는 반면 대형 개체들이 광양만에 분포하여 크기에 따른 서식처 분리를 나타내었다. 결론적으로 본 연구에서 나타난 주둥치의 δ13C 값의 서식처 간 차이와 δ15N 값의 일관성은 섬진강 하구에서 유어기에 주로 동물플랑크톤을 섭이하는 반면, 광양만에서 성어기에 저서무척추동물을 섭이하는 육식성 섭식 특성과 함께 이동 중 서식환경에 따른 먹이자원의 이용에서의 변이를 잘 나타내어 주었다. 본 연구결과는 또한 광염성 어류의 서식처 특성과 먹이 이용 패턴을 파악하기 위한 연구에 안정동위원소 분석기법의 유용성을 잘 보여주었다.

A Methodological Shift in Building Design through Development of Collaborative Design Platforms

  • Schumacher, Jonatan;Naugle, Matthew
    • 국제초고층학회논문집
    • /
    • 제3권4호
    • /
    • pp.279-283
    • /
    • 2014
  • This paper introduces two platforms created by the development team at CORE studio, Thornton Tomasetti's global innovation studio. Collaborative platforms change the way that parties communicate and develop projects. Wikipedia is one of many great examples for a platform that supports collaborative development of a product - the world's largest encyclopedia. In the AEC industry, no such platform exists that can be used for collaborative development of a building project, and hence, information exchange between the parties involved, and modeling programs used in a project is slow and opaque. The platforms introduced in this paper allow for much greater transparency at all stages of the building design process, and hence improve the flow of information between parties involved in the process, both firm-internal and external. While traditionally, the use of a large number of different modeling and analysis platforms is hard to manage by a project team; this paper introduces methods that strengthen the design process by using a multitude of programs needed in the different building design phases.

Post-disturbance Recovery Pattern in the Soft Corals-Macroalgae Mixed Habitat in Jeju Island, Korea

  • Kim, Junsu;Hong, Seokwoo;Yang, Kwon Mo;Macias, Daniela;Kim, Jeong Ha
    • 한국해양생명과학회지
    • /
    • 제6권2호
    • /
    • pp.117-123
    • /
    • 2021
  • Post-disturbance recovery pattern of subtidal soft corals-macroalgae mixed community and the role of water depth were investigated. The experiment was conducted in a subtidal rock wall of Munseom, Jeju Island, Korea for 2.5 years. Artificial disturbance was done at established treatment plots at depths of 10, 15 and 20 m and were then compared with undisturbed control plots. After disturbance, recovery of soft corals was very slow, whereas macroalgae quickly occupied the plots and reached a similar level as the control in 6 months, and this pattern was consistent at all water depths. This unbalanced speed of recovery caused higher macroalgae establishment than soft corals in treatment compared to control plots, indicating a possible phase shift in the community structure. This study provides an important implication for the necessity of monitoring the influence of disturbance at a larger scale, from a conservation perspective of soft corals in Jeju coast.

Contribution of Reinforced Concrete Floor Slabs to Lateral Behavior of Tall Buildings

  • Rehmanjee, Yasmin;Leslie, Benjamin;Lamianski, Dmitri;Chafart, Manuel
    • 국제초고층학회논문집
    • /
    • 제11권1호
    • /
    • pp.25-29
    • /
    • 2022
  • This paper focuses on how the coupling of the columns and walls through the structural slab contributes to the overall stiffness and strength of lateral systems. The rationale and procedures behind the design approach, which may offer a shift from more conventional assumptions made regarding compatibility and connectivity of gravity and lateral structural systems, will be introduced. The impacts on serviceability and strength design will be discussed, and observations on key design and analysis approaches will be featured. Mass and stiffness assumptions will also be reviewed. A case study on the topic will be presented describing implementation of slab coupling into engineering of a building project.