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1.
Proc Natl Acad Sci U S A ; 120(46): e2311548120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37931096

RESUMO

We address a generalization of the concept of metapopulation capacity for trees and networks acting as the template for ecological interactions. The original measure had been derived from an insightful phenomenological model and is based on the leading eigenvalue of a suitable landscape matrix. It yields a versatile predictor of metapopulation persistence through a threshold value of the eigenvalue determined by ecological features of the focal species. Here, we present an analytical solution to a fundamental microscopic model that incorporates key ingredients of metapopulation dynamics and explicitly distinguishes between individuals comprising the "settled population" and "explorers" seeking colonization. Our approach accounts for general network characteristics (in particular graph-driven directional dispersal which is known to significantly constrain many ecological estimates) and yields a generalized version of the original model, to which it reduces for particular cases. Through examples, including real landscapes used as the template, we compare the predictions from our approach with those of the standard model. Results suggest that in several cases of practical interest, differences are significant. We also examine, with both models, how changes in habitat fragmentation, including removal, addition, or alteration in size, affect metapopulation persistence. The current approach demonstrates a high level of flexibility, enabling the incorporation of diverse "microscopic" elements and their impact on the resulting biodiversity landscape pattern.


Assuntos
Ecossistema , Modelos Biológicos , Humanos , Dinâmica Populacional , Biodiversidade , Árvores
2.
BMC Health Serv Res ; 24(1): 115, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254104

RESUMO

BACKGROUND: Developing countries such as Kenya still experience challenges around human resource to deliver refractive error services. However, given the burden of uncorrected refractive error, adoption of innovative and cost effective approaches is desirable. Hence this study intended to develop a task shifting framework integrated with telemedicine to potentially scale refractive error services. METHODS: This was an exploratory study conducted in four phases as follows: a scoping review of the scope of practice for ophthalmic workers in Kenya, an interview with key opinion leaders on the need for integration of public health approaches such as the vision corridors within the eye health ecosystem in Kenya and their knowledge on task shifting, and finally development and validation of a proposed task shifting framework through a Delphi technique. Purposive sampling was used to recruit key opinion leaders and data was collected via telephonic interviews. The qualitative data was analyzed thematically using NVivo Software, Version 11. RESULTS: The scoping review showed that only optometrists, ophthalmologists and ophthalmic clinical officers are allowed to undertake refraction in Kenya. All of the key opinion leaders (100%) were aware of task shifting and agreed that it is suitable for adoption within the eye health ecosystem in Kenya. All of the key opinion leaders (100%) agreed that skills development for healthcare workers without prior training on eye health supervised by optometrists through telemedicine is desirable. Notwithstanding, all of the key opinion leaders (100%) agreed that integration of public health approaches such as the vision corridors across all levels of healthcare delivery channels and development of a self-assessment visual acuity tool is desirable. Finally all of the key opinion leaders (100%) agreed that task shifting is relevant for adoption within the eye health ecosystem in Kenya. The developed framework prioritized partnership, advocacy, skills development, establishment and equipping of refraction points. The proposed framework advocated for a telemedicine between professionals with conventional training and those with skills development. CONCLUSION: Task shifting integrated with telemedicine could cost effectively scale refractive error service delivery. However, internal and external factors may hinder the success warranting the need for a multi-faceted interventions and a connection between planning and training to scale the uptake.


Assuntos
Erros de Refração , Telemedicina , Humanos , Quênia , Técnica Delphi , Ecossistema , Revezamento de Tarefas , Erros de Refração/terapia
3.
J Environ Manage ; 365: 121512, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38897083

RESUMO

The construction of ecological networks within the context of urbanization is an effective approach to cope with the challenges of urban biodiversity decline, representing a crucial goal in urban planning and development. However, existing studies often overlook the richness and uniqueness within species communities by homogenizing traits of species in the same class. This study proposes a framework for constructing and optimizing ecological networks focused on differential conservation within the same class. By classifying birds into three groups (specialists of water, forest or urban areas) based on their ecological requirements and urbanization tolerance, we constructed an ecological network tailored to their distinct migratory dispersal patterns. We then identified strategic areas including pinch points, barriers, and breakpoints specific to each bird group. Our findings reveal notable variations in suitable habitat distribution among different bird groups in urban environments. Corridor layouts varied according to habitat preferences and migratory dispersal patterns. Despite these differences, urban built-up areas persist as central hubs for the distribution of suitable habitats for 75% of bird species, with peripheral mountain-plain transition areas constituting 63% of crucial dispersal corridors. This emphasizes the critical role of urban built-up areas in maintaining biodiversity and ecological connectivity. Prioritizing connectivity between central urban areas and distant natural spaces is imperative. Our approach innovatively classifies and constructs networks to identify strategic areas with diverse species-specific attributes, providing valuable spatial information for land planning and guiding solutions to enhance target species. While the primary focus is on bird conservation in Beijing, our framework is broadly applicable to global biodiversity management and green planning under urbanization challenges. Overall, this study offers innovative insights for urban planning development and serves as decision support for prioritizing urban actions.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Urbanização , Conservação dos Recursos Naturais/métodos , Animais , Aves
4.
Environ Monit Assess ; 196(10): 936, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283349

RESUMO

Wildlife and natural resources constitute an integral part of the ecosystem, whereas human interventions dismantled the living conditions of the wildlife. This is testified in the Dalma Wildlife Sanctuary (DWS) where the habitats of Asian elephants have changed due to human intervention and deforestation over the decades. The present study aimed to assess the elephant habitat suitability in the DWS of Jharkhand state (India) using the geospatial parameters such as forest density, degree of slope, proximity to water bodies, land use land cover, proximity to agricultural land, built-up density, and road density. The analytical hierarchical process technique was utilized to determine habitat preference and selection of relevant factors to categorize criteria. The study revealed that about 6.7% (26.74 km2) of the area is very highly suitable for elephant habitat, while 52.26% (208.49 km2) of the forest area was found highly suitable. The most suitable habitat was identified in the core parts of the forest, while the least suitable areas were found in the southern part, where the presence of roads, built-up, and agricultural land was prominent. It was also observed that most human-elephant conflicts were exhibited in the low and very low suitable areas, while 90% of the elephant movement was witnessed in the high and very high suitable areas. Among the four identified corridors, three are inactive, and their location corresponds with low to very low suitable habitats. The study identified the migratory corridor routes inside the sanctuary where effective management is required for the conservation of elephant habitats and minimizing conflicts.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Elefantes , Animais , Índia , Florestas , Monitoramento Ambiental/métodos , Animais Selvagens
5.
Mol Ecol ; 32(3): 644-659, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36380736

RESUMO

Geographical features and palaeoclimatic fluctuations are two classical evolutionary forces that shape genetic diversification within species. Fine-grained analysis of the mechanisms involved through population demographic processes, however, remains limited. Taking advantage of two recently published reference genomes, we resequenced the genomes and examined the evolutionary history of the moustache toads, a group endemic to East Asia where complex topography and fluctuating palaeoclimate are known to have had profound impacts on organisms. Moustache toads probably originated in southeast Yunnan, China, and diversified towards the northwestern of Yunnan, as well as central and eastern China. Further exploration based on three widespread species (Leptobrachium ailaonicum, L. boringii and L. liui) using demographic modelling and species distribution models revealed that mountains and river valleys in East Asia not only functioned as geographical barriers, but also provided dispersal corridors and facilitated continuous migration or post-glacial secondary contact among moustache toad populations. Furthermore, periodic oscillation of effective population sizes accompanying fluctuations of historical temperature and population contraction at the Last Glacial Maximum support the widespread impact of climatic changes of the Pleistocene on species diversification in East Asia. This impact was moderate for populations of L. ailaonicum and L. boringii in the southwestern mountains but severe for populations of L. liui in the eastern lowland regions of continental East Asia, which is supported by different degrees of change of their effective population sizes. Our findings reveal mechanisms underlying genetic diversification among moustache toads, and highlight the power of genomic data and demographic modelling for examining complex historical population-level processes and for understanding how geographical and palaeoclimatic factors interactively shape current intraspecific diversity.


Assuntos
Anuros , Evolução Biológica , Animais , Filogenia , China , Ásia Oriental , Geografia , Anuros/genética
6.
J Esthet Restor Dent ; 35(2): 345-351, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36628925

RESUMO

OBJECTIVE: To investigate whether there is a relationship between the distance between the iris and pupil with the ideal size of buccal corridors. MATERIALS AND METHODS: A full-portrait image of a male Caucasian was used to create a set of 11 digitally modified images with different buccal corridor space. A web-based cross-sectional study was designed and distributed via an online survey to 200 laypeople and 200 orthodontists to assess image attractiveness, using a Visual analogue scale. For the statistical analysis, Wilcoxon signed-rank and Mann-Whitney U tests were used. The significance level was set at p < 0.05. RESULTS: The response rate for laypeople was 70% (n = 139), while the rate for orthodontists was 73% (n = 146). For the layperson group, the maximum smile attractiveness score was 10% of buccal width reduction, compared to the iris-pupillary distance, while for the orthodontists, it was 20%. The attractiveness of the smile was significantly reduced in both groups when the buccal corridor width was increased in comparison to the iris-pupillary distance. CONCLUSION: The length between the mesial part of the iris and the distal of the pupil, may constitutes a landmark for the estimation of the desired width of the buccal corridor. CLINICAL RELEVANCE: Inter iris-pupillary distance can be the starting point in the smile designing process, in order to perform a facial driven selection of buccal corridor size.


Assuntos
Ortodontistas , Sorriso , Masculino , Humanos , Estudos Transversais , Sorriso/fisiologia , Face , Percepção , Estética Dentária , Atitude do Pessoal de Saúde
7.
J Fish Biol ; 102(2): 492-503, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36451613

RESUMO

Little is known about manta ray population size, structure and connectivity in the Philippines. In collaboration with dive operators, non-governmental organizations and authorities, sightings of manta rays were collated into a single national database. Using in-water photographs and videos gathered through citizen science and dedicated research efforts, this study compiled sightings between 2004 and 2020, showing 22 separate sites throughout the archipelago with manta rays present. A total of 392 individual reef manta rays (Mobula alfredi) and 107 oceanic manta rays (Mobula birostris) were identified from the collected footage. Four specific sites in the provinces of Masbate and Palawan together hosted 89% of all identified individuals and accounted for 95% of sightings, highlighting these areas are key aggregation sites. This study also reports the movements of M. birostris within the Philippines, based on photo-identification of three individuals moving 150 km between Cebu and Masbate. Despite the growing number of recreational divers in Daanbantayan and San Jacinto, an 80% decline in M. birostris sightings was observed at these sites. To ensure effective future conservation, it is recommended that efforts focus on the identification and protection of manta ray hotspots and migratory corridors, the creation of a sustainable tourism framework and, most important, the implementation of mitigation strategies to reduce fisheries interactions.


Assuntos
Elasmobrânquios , Rajidae , Animais , Filipinas , Oceanos e Mares , Pesqueiros
8.
J Environ Manage ; 336: 117692, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36921475

RESUMO

Rapid urbanization has resulted in fragmentation and decreased connectivity in urban landscapes, endangering regional biodiversity conservation and high-quality, sustainable development. networks (ENs) construction and optimization is a critical technique to enhance landscape connectivity effectively, promote species interaction and dispersal, and thereby hence urban biodiversity., most existing studies on ENs construction have been undertaken from the perspective of ecosystem service functions or the value of landscape structure, with regional species still being overlooked. on the distribution data of critical species in this study, the maximum entropy model (MaxEnt), wilderness mapping model, and granularity reverse method were integrated to identify ecological sources. the habitat quality (HQ) index was utilized to construct a resistance surface modified by landscape connectivity and ecological sensitivity. findings indicate that: (1) a grid scale of 1700 m is the relatively optimal minimum threshold for ecological source sites in Guangzhou; (2) 35 crucial ecological sources in Guangzhou are identified, with a total area of 1100.42 km2, mainly woodlands, distributed in mountain systems in the northern and central parts of the city; and (3) 59 ecological corridors are identified, with a total length of 817.4 km, with a relatively high density in the central part of the city. some extent, this study offers fresh ideas for constructing urban ENs from the standpoint of biodiversity conservation. contributes to the city achieving a win-win economic development and ecological protection situation.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Florestas , Cidades , China , Ecologia
9.
Environ Monit Assess ; 196(1): 61, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38110623

RESUMO

Climate change affects ecosystems in different ways. These effects are particularly worrying in the Neotropical region, where species are most vulnerable to these changes because they live closer to their thermal safety limits. Thus, establishing conservation priorities, particularly for the definition of protected areas (PAs), is a priority. However, some PA systems within the Neotropics are ineffective even under the present environmental conditions. Here, we test the effectiveness of a PA system, within an ecotone in northern Brazil, in protecting 24 endangered bird species under current and future (RCP8.5) climatic scenarios. We used species distribution modeling and dispersal corridor modeling to describe the priority areas for conservation of these species. Our results indicate that several threatened bird taxa are and will potentially be protected (i.e., occur within PAs). Nonetheless, the amount of protected area is insufficient to maintain the species in the ecotone. Moreover, most taxa will probably present drastic declines in their range sizes; some are even predicted to go globally extinct soon. Thus, we highlight the location of a potentially effective system of dispersal corridors that connects PAs in the ecotone. We reinforce the need to implement public policies and raise public awareness to maintain PAs and mitigate anthropogenic effects within them, corridors, and adjacent areas, aiming to conserve the richness and diversity of these already threatened species.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental , Espécies em Perigo de Extinção , Aves , Mudança Climática , Biodiversidade
10.
High Educ Policy ; 36(1): 213-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34594095

RESUMO

Connectivity in both its tangible and intangible forms is a fundamental feature of all aspects of university life though often overlooked in much of the relevant literature. Using the metaphor of the couloir, this paper will examine features of university design and organisation which contribute to this connectivity, in its various senses, across the institution. A typology of connectivity features is proposed, setting efficiency of movement against possibilities for social interaction, with another axis contrasting open/public against closed/private spaces. Universities, which everywhere have both public and private dimensions, seem to have features that occupy a central place in this typology, highlighting the multifaceted nature of connectivity in university life. The significance of connectivity should inform a range of institutional policies affecting space design and use as well as methods in teaching and learning.

11.
Mol Ecol ; 31(12): 3451-3467, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35510775

RESUMO

The main objective of this study was to evaluate biogeographical hypotheses of diversification and connection between isolated savannas north (Amazonian savannas) and south (Cerrado core) of the Amazon River. To achieve this, we used genomic markers (genotyping-by-sequencing) to evaluate the genetic structure, population phylogenetic relationships and historical range shifts of four Neotropical passerines with peri-Atlantic distributions: the narrow-billed woodcreeper (Lepidocolaptes angustirostris), the plain-crested elaenia (Elaenia cristata), the grassland sparrow (Ammodramus humeralis) and the white-banded tanager (Neothraupis fasciata). Population genetic analyses indicated that landscape (e.g., geographic distance, landscape resistance and percentage of tree cover) and climate metrics explained divergence among populations in most species, but without indicating a differential role between current and historical factors. Our results did not fully support the hypothesis that isolated populations in Amazonian savannas have been recently derived from the Cerrado core domain. Intraspecific phylogenies and gene flow analyses supported multiple routes of connection between the Cerrado and Amazonian savannas, rejecting the hypothesis that the Atlantic corridor explains the peri-Atlantic distribution. Our results reveal that the biogeographical history of the region is complex and cannot be explained by simple vicariant models.


Assuntos
Pradaria , Passeriformes , Animais , Teorema de Bayes , Fluxo Gênico , Passeriformes/genética , Filogenia , Filogeografia , Rios
12.
Conserv Biol ; 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288989

RESUMO

As ecological data and associated analyses become more widely available, synthesizing results for effective communication with stakeholders is essential. In the case of wildlife corridors, managers in human-dominated landscapes need to identify both the locations of corridors and multiple stakeholders for effective oversight. We synthesized 5 independent studies of tiger (Panthera tigris) connectivity in central India, a global priority landscape for tiger conservation, to quantify agreement on landscape permeability for tiger movement and potential movement pathways. We used the latter analysis to identify connectivity areas on which studies agreed and stakeholders associated with these areas to determine relevant participants in corridor management. Three or more of the 5 studies' resistance layers agreed in 63% of the study area. Areas in which all studies agree on resistance were of primarily low (66%, e.g., forest) and high (24%, e.g., urban) resistance. Agreement was lower in intermediate resistance areas (e.g., agriculture). Despite these differences, the studies largely agreed on areas with high levels of potential movement: >40% of high average (top 20%) current-flow pixels were also in the top 20% of current-flow agreement pixels (measured by low variation), indicating consensus connectivity areas (CCAs) as conservation priorities. Roughly 70% of the CCAs fell within village administrative boundaries, and 100% overlapped forest department management boundaries, suggesting that people live and use forests within these priority areas. Over 16% of total CCAs' area was within 1 km of linear infrastructure (437 road, 170 railway, 179 transmission line, and 339 canal crossings; 105 mines within 1 km of CCAs). In 2019, 78% of forest land diversions for infrastructure and mining in Madhya Pradesh (which comprises most of the study region) took place in districts with CCAs. Acute competition for land in this landscape with globally important wildlife corridors calls for an effective comanagement strategy involving local communities, forest departments, Appendix 1 and infrastructure planners. This article is protected by copyright. All rights reserved.

13.
J Environ Manage ; 316: 115254, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35576714

RESUMO

Increasing urbanization degrades quantity, quality, and the functionality of spatial cohesion of natural areas essential to biodiversity and ecosystem functioning worldwide. The uncontrolled pace of building activity and the erosion of blue (i.e., aquatic) and green (i.e., terrestrial) landscape elements threaten existing habitat ranges and movability of wildlife. Local scale measures, such as nature-inspired engineered Blue-Green Infrastructure (BGI) are emerging mitigation solutions. Originally planned to promote sustainable stormwater management, adaptation to climate change and improved human livability in cities, such instruments offer interesting synergies for biodiversity in support of existing ecological infrastructure. BGI are especially appealing for globally declining amphibians, a rich and diverse vertebrate assemblage sensitive to urbanization. We integrated biological and highly resolved urban-rural land-cover data, ensemble models of habitat suitability, and connectivity models based on circuit theory to improve multi-scale and multi-species protection of core habitats and ecological corridors in the Swiss lowlands. Considering a broad spectrum of amphibian biodiversity, we identified distributions of amphibian biodiversity hotspots and four landscape elements essential to amphibian movability at the regional scale, namely i) forest edges, ii) wet-forest habitats, iii) soils with variable moisture and iv) riparian zones. Our work shows that cities can make a substantial contribution (e.g., up to 15% of urban space in the study area) to wider landscape habitat connectivity. We highlight the importance of planning BGI locally in strategic locations across urban and peri-urban areas to promote the permeability and availability of 'stepping stone' habitats in densely populated landscapes, essential to the maintenance of regional habitat connectivity and thereby enhancing biodiversity and ecosystem functioning.


Assuntos
Biodiversidade , Ecossistema , Cidades , Conservação dos Recursos Naturais , Florestas , Humanos , Urbanização
14.
J Environ Manage ; 311: 114846, 2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35290956

RESUMO

Roadsides, in particular those being species-rich and of conservation value, are considered to improve landscape permeability by providing corridors among habitat patches and by facilitating species' dispersal. However, little is known about the potential connectivity offered by such high-value roadsides. Using circuit theory, we modelled connectivity provided by high-value roadsides in landscapes with low or high permeability in south-central Sweden, with 'permeability' being measured by the area of semi-natural grasslands. We modelled structural connectivity and, for habitat generalists and specialists, potential functional connectivity focusing on butterflies. We further assessed in which landscapes grassland connectivity is best enhanced through measures for expanding the area of high-value roadsides. Structural connectivity provided by high-value roadsides resulted in similar patterns to those of a functional approach, in which we modelled habitat generalists. In landscapes with low permeability, all target species showed higher movements within compared to between grasslands using high-value roadsides. In landscapes with high permeability, grassland generalists and specialists showed the same patterns, whereas for habitat generalists, connectivity provided by high-value roadsides and grasslands was similar. Increasing the ratio of high-value roadsides can thus enhance structural and functional connectivity in landscapes with low permeability. In contrast, in landscapes with high permeability, roadsides only supported movement of specialised species. Continuous segments of high-value roadsides are most efficient to increase connectivity for specialists, whereas generalists can utilize also short segments of high-value roadsides acting as stepping-stones. Thus, land management should focus on the preservation and restoration of existing semi-natural grasslands. Management for enhancing grassland connectivity through high-value roadsides should aim at maintaining and creating high-value roadside vegetation, preferably in long continuous segments, especially in landscapes with low permeability.

15.
J Environ Manage ; 321: 116023, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36007382

RESUMO

Alien invasive plant species are one of the main drivers of global biodiversity loss. Methods for monitoring the spread of alien invasive plants are needed to improve management and mitigate impact on local biodiversity. Recent advances in deep learning and image fusion holds great potential for mapping and managing alien invasive plants. One such method is super-resolution image reconstruction, where a neural network learns to downscale images from coarse to fine resolution. Within the commercial timber production landscape of KwaZulu-Natal, endangered grassland corridors are threatened by American bramble invasion, impacting plants, birds, arthropods, and soil restoration. Here we aim to improve our understanding of bramble invasion dynamics through using super-resolved satellite mosaics. Bramble was classified with very high accuracies (85%) from the super-resolved satellite mosaic, compared to other conventional satellite imagery with different spectral and spatial resolutions. Using landscape analyses, we identified plantation tree harvesting and prescribed burning to be major drivers increasing bramble cover within the landscape. Bramble cover was highest one year following plantation tree harvesting. Continuous prescribed burning positively influenced bramble. Bramble cover was also high close to streams, and under future invasion projections, bramble will severely impact Ensifera species alongside low priority grasshopper species habitat. Results also indicate that bramble has a significant negative impact on intermediate priority grasshoppers and plant species richness. For controlling bramble invasion within commercial timber production landscapes, we recommend the adoption rotational harvesting, as harvesting entire plantation blocks throughout the landscape will dramatically increase invasion potential of bramble. Current bramble removal programmes should prioritize riparian areas. Special attention is needed to control bramble one year after timber harvesting, as this is when bramble cover is highest. We show the benefits of using super-resolved mosaics to gain new insights into alien invasive species dynamics, while further development of this technique will aid in managing invasive alien plant species at local scales.


Assuntos
Espécies Introduzidas , Imagens de Satélites , Animais , Biodiversidade , Aves , Conservação dos Recursos Naturais/métodos , Ecossistema , Plantas , África do Sul , Árvores
16.
Ann Bot ; 128(3): 315-327, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34057991

RESUMO

BACKGROUND AND AIMS: Hedgerows have been shown to improve forest connectivity, leading to an increased probability of species tracking the shifting bioclimatic envelopes. However, it is still unknown how species in hedgerows respond to temperature changes, and whether effects differ compared with those in nearby forests. We aimed to elucidate how ongoing changes in the climate system will affect the efficiency of hedgerows in supporting forest plant persistence and migration in agricultural landscapes. METHODS: Here we report results from the first warming experiment in hedgerows. We combined reciprocal transplantation of plants along an 860-km latitudinal transect with experimental warming to assess the effects of temperature on vegetative growth and reproduction of two common forest herbs (Anemone nemorosa and Geum urbanum) in hedgerows versus forests. KEY RESULTS: Both species grew taller and produced more biomass in forests than in hedgerows, most likely due to higher competition with ruderals and graminoids in hedgerows. Adult plant performance of both species generally benefitted from experimental warming, despite lower survival of A. nemorosa in heated plots. Transplantation affected the species differently: A. nemorosa plants grew taller, produced more biomass and showed higher survival when transplanted at their home site, indicating local adaptation, while individuals of G. urbanum showed greater height, biomass, reproductive output and survival when transplanted northwards, likely owing to the higher light availability associated with increasing photoperiod during the growing season. CONCLUSIONS: These findings demonstrate that some forest herbs can show phenotypic plasticity to warming temperatures, potentially increasing their ability to benefit from hedgerows as ecological corridors. Our study thus provides novel insights into the impacts of climate change on understorey plant community dynamics in hedgerows, and how rising temperature can influence the efficiency of these corridors to assist forest species' persistence and colonization within and beyond their current distribution range.


Assuntos
Florestas , Plantas , Biomassa , Mudança Climática , Ecossistema , Temperatura
17.
Ecol Appl ; 31(6): e02387, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34137106

RESUMO

Connecting protected areas remains an important global conservation strategy in the face of ongoing and future threats to biodiversity. Amid our growing understanding of how species' distributions will respond to climate change, conservation scientists need to plan for connectivity conservation across entire continents. We modeled multiscale connectivity priorities based on the least human-modified lands between large protected areas of North America using least-cost and circuit theory approaches. We first identified priority corridors between large protected areas, then characterized the network's structure to unveil priority linkages most important for maintaining network- and regional-level connectivity. Agreement between least-cost corridors and current flow varied throughout North America, reflecting permeable landscape conditions and "pinch points" where potential ecological flows may concentrate between protected areas. Priority network-level linkages derived from each approach were similar throughout the continental network (e.g., Rocky Mountains and Canadian boreal), but critical linkages that bridged regional protected-area networks varied. We emphasize the importance of planning for connectivity at continental scales and demonstrate the utility of multiple methods when mapping connectivity priorities across large spatial extents with wide gradients in landscape conditions.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Canadá , Humanos , América do Norte
18.
Health Econ ; 30(6): 1443-1460, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33797143

RESUMO

Many insurance markets have reinstated premium stabilization programs to ensure financial protection from market volatility. In this paper, we focus on one such regulation-risk corridors (RCs)-in the context of the Health Insurance Marketplaces established under the Affordable Care Act. We develop a model to show how the program provided incentives for some insurers to lower their premiums. The RCs program was defunded unexpectedly for coverage year 2016, before its legislated end in 2016. Consistent with the model, we find that making a RCs claim before the program ended is associated with higher premium growth after the program's demise. The model and empirical evidence are consistent with the view that the end of the RCs program contributed to premium growth in the Marketplaces.


Assuntos
Trocas de Seguro de Saúde , Patient Protection and Affordable Care Act , Humanos , Seguradoras , Cobertura do Seguro , Seguro Saúde , Participação no Risco Financeiro , Estados Unidos
19.
Sensors (Basel) ; 21(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477511

RESUMO

Considering the complexity of the physical model of wildfire occurrence, this paper develops a method to evaluate the wildfire risk of transmission-line corridors based on Naïve Bayes Network (NBN). First, the data of 14 wildfire-related factors including anthropogenic, physiographic, and meteorologic factors, were collected and analyzed. Then, the relief algorithm is used to rank the importance of factors according to their impacts on wildfire occurrence. After eliminating the least important factors in turn, an optimal wildfire risk assessment model for transmission-line corridors was constructed based on the NBN. Finally, this model was carried out and visualized in Guangxi province in southern China. Then a cost function was proposed to further verify the applicability of the wildfire risk distribution map. The fire events monitored by satellites during the first season in 2020 shows that 81.8% of fires fall in high- and very-high-risk regions.

20.
Sensors (Basel) ; 21(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34833612

RESUMO

With the advancement of urbanization and the impact of industrial pollution, the issue of urban ventilation has attracted increasing attention. Research on urban ventilation corridors is a hotspot in the field of urban planning. Traditional studies on ventilation corridors mostly focus on qualitative or simulated research on urban climate issues such as the intensified urban heat island effect, serious environmental pollution, and insufficient climate adaptability. Based on the high-precision urban remote sensing image data obtained by aeromagnetic oblique photography, this paper calculates the frontal area density of the city with reference to the urban wind statistics. Based on the existing urban patterns, template matching technology was used to automatically excavate urban ventilation corridors, which provides scientific and reasonable algorithmic support for the rapid construction of potential urban ventilation corridor paths. It also provides technical methods and decision basis for low-carbon urban planning, ecological planning and microclimate optimization design. This method was proved to be effective through experiments in Deqing city, Zhejiang Province, China.


Assuntos
Planejamento de Cidades , Temperatura Alta , China , Cidades , Urbanização , Ventilação
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