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1.
Nature ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169178

RESUMO

Conservation, restoration and land management are increasingly implemented at landscape scales1,2. However, because species interaction data are typically habitat- and/or guild-specific, exactly how those interactions connect habitats and affect the stability and function of communities at landscape scales remains poorly understood. We combine multi-guild species interaction data (plant-pollinator and three plant-herbivore-parasitoid communities, collected from landscapes with one, two or three habitats), a field experiment and a modelling approach to show that multi-habitat landscapes support higher species and interaction evenness, more complementary species interactions and more consistent robustness to species loss. These emergent network properties drive improved pollination success in landscapes with more habitats and are not explained by simply summing component habitat webs. Linking landscape composition, through community structure, to ecosystem function, highlights mechanisms by which several contiguous habitats can support landscape-scale ecosystem services.

2.
Nature ; 530(7588): 85-8, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26842058

RESUMO

There is considerable concern over declines in insect pollinator communities and potential impacts on the pollination of crops and wildflowers. Among the multiple pressures facing pollinators, decreasing floral resources due to habitat loss and degradation has been suggested as a key contributing factor. However, a lack of quantitative data has hampered testing for historical changes in floral resources. Here we show that overall floral rewards can be estimated at a national scale by combining vegetation surveys and direct nectar measurements. We find evidence for substantial losses in nectar resources in England and Wales between the 1930s and 1970s; however, total nectar provision in Great Britain as a whole had stabilized by 1978, and increased from 1998 to 2007. These findings concur with trends in pollinator diversity, which declined in the mid-twentieth century but stabilized more recently. The diversity of nectar sources declined from 1978 to 1990 and thereafter in some habitats, with four plant species accounting for over 50% of national nectar provision in 2007. Calcareous grassland, broadleaved woodland and neutral grassland are the habitats that produce the greatest amount of nectar per unit area from the most diverse sources, whereas arable land is the poorest with respect to amount of nectar per unit area and diversity of nectar sources. Although agri-environment schemes add resources to arable landscapes, their national contribution is low. Owing to their large area, improved grasslands could add substantially to national nectar provision if they were managed to increase floral resource provision. This national-scale assessment of floral resource provision affords new insights into the links between plant and pollinator declines, and offers considerable opportunities for conservation.


Assuntos
Biodiversidade , Flores/química , Flores/crescimento & desenvolvimento , Néctar de Plantas/análise , Plantas/química , Plantas/classificação , Animais , Flores/classificação , Pradaria , Insetos/fisiologia , Medicago/química , Medicago/crescimento & desenvolvimento , Plantas/metabolismo , Polinização , Especificidade da Espécie , Reino Unido
3.
Med Teach ; 43(11): 1255-1260, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33253603

RESUMO

When students attend clinical attachments in diverse locations, a key challenge is in ensuring consistently good teaching over all areas. To meet this challenge, a faculty development intervention called TiMEtoTeach was created with the aim of reaching all involved in teaching medical students. The programme takes a holistic view of workplace (professional clinical attachments) learning with the recognition of all who are part of the student learning journey, including staff in clinical environments, charitable organisations, fellow students and the patients and carers. Empowering and upskilling this diverse group, we create a Universal Faculty. We engage this group with a comprehensive and accessible faculty development programme, enabling a consistent, authentic, and realistic learning experience for students. This supports graduate preparedness for their roles as junior doctors. The twelve tips described in this article relate to simple, achievable processes that faculty developers within medical education can apply to help improve consistency and quality in clinical workplace experience for students, recognising the challenges of engaging the large and diverse group of people who support education within the clinical arena.


Assuntos
Educação Médica , Estudantes de Medicina , Docentes , Docentes de Medicina , Humanos , Aprendizagem , Corpo Clínico Hospitalar , Ensino
4.
Ecol Lett ; 22(9): 1367-1377, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207056

RESUMO

In network ecology, landscape-scale processes are often overlooked, yet there is increasing evidence that species and interactions spill over between habitats, calling for further study of interhabitat dependencies. Here, we investigate how species connect a mosaic of habitats based on the spatial variation of their mutualistic and antagonistic interactions using two multilayer networks, combining pollination, herbivory and parasitism in the UK and New Zealand. Developing novel methods of network analysis for landscape-scale ecological networks, we discovered that few plant and pollinator species acted as connectors or hubs, both within and among habitats, whereas herbivores and parasitoids typically have more peripheral network roles. Insect species' roles depend on factors other than just the abundance of taxa in the lower trophic level, exemplified by larger Hymenoptera connecting networks of different habitats and insects relying on different resources across different habitats. Our findings provide a broader perspective for landscape-scale management and ecological community conservation.


Assuntos
Ecossistema , Herbivoria , Insetos , Polinização , Animais , Nova Zelândia , Reino Unido
7.
Philos Trans R Soc Lond B Biol Sci ; 377(1853): 20210172, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35491602

RESUMO

Research into pollinators in managed landscapes has recently combined approaches of pollination ecology and landscape ecology, because key stressors are likely to interact across wide areas. While laboratory and field experiments are valuable for furthering understanding, studies are required to investigate the interacting drivers of pollinator health and diversity across a broader range of landscapes and a wider array of taxa. Here, we use a network of 96 study landscapes in six topographically diverse regions of Britain, to test the combined importance of honeybee density, insecticide loadings, floral resource availability and habitat diversity to pollinator communities. We also explore the interactions between these drivers and the cover and proximity of semi-natural habitat. We found that among our four drivers, only honeybee density was positively related to wild pollinator abundance and diversity, and the positive association between abundance and floral resources depended on insecticide loadings and habitat diversity. By contrast, our exploratory models including habitat composition metrics revealed a complex suite of interactive effects. These results demonstrate that improving pollinator community composition and health is unlikely to be achieved with general resource enhancements only. Rather, local land-use context should be considered in fine-tuning pollinator management and conservation. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.


Assuntos
Agricultura , Inseticidas , Animais , Abelhas , Ecologia , Ecossistema , Polinização
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