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421.
Theory predicts that damage by a shared herbivore to a secondary host plant species may either be higher or lower in the vicinity of a preferred host plant species. To evaluate the importance of ecological factors, such as host plant proximity and density, in determining the direction and strength of such herbivore-mediated indirect effects, we quantified oviposition by the exotic weevil Rhinocyllus conicus on the native wavyleaf thistle Cirsium undulatum in midgrass prairie on loam soils in the upper Great Plains, USA. Over three years (2001-2003), the number of eggs laid by R. conicus on C. undulatum always decreased significantly with distance (0-220 m) from a musk thistle (Carduus nutans L.) patch. Neither the level of R. conicus oviposition on C. undulatum nor the strength of the distance effect was predicted by local musk thistle patch density or by local C. undulatum density (<5 m). The results suggest that high R. conicus egg loads on C. undulatum near musk thistle resulted from the native thistle's co-occurrence with the coevolved preferred exotic host plant and not from the weevil's response to local host plant density. Mean egg loads on C. undulatum also were greater at sites with higher R. conicus densities. We conclude that both preferred-plant proximity and shared herbivore density strongly affected the herbivore-mediated indirect interaction, suggesting that such interactions are important pathways by which invasive exotic weeds can indirectly impact native plants. 相似文献
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Laura Bouriaud Mariella Marzano Manfred Lexer Liviu Nichiforel Christopher Reyer Christian Temperli Heli Peltola Ché Elkin Gabriel Duduman Philip Taylor Stephen Bathgate Jose G. Borges Sandra Clerkx Jordi Garcia-Gonzalo Carlos Gracia Geerten Hengeveld Seppo Kellomäki Georgi Kostov Michael Maroschek Bart Muys Gert-Jan Nabuurs Bruce Nicoll Marc Palahí Werner Rammer Duncan Ray Mart-Jan Schelhaas Louise Sing Margarida Tomé Juergen Zell Marc Hanewinkel 《Regional Environmental Change》2015,15(8):1595-1609
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Abigail Bennett Xavier Basurto John Virdin Xinyan Lin Samantha J. Betances Martin D. Smith Edward H. Allison Barbara A. Best Kelly D. Brownell Lisa M. Campbell Christopher D. Golden Elizabeth Havice Christina C. Hicks Peter J. Jacques Kristin Kleisner Niels Lindquist Rafaella Lobo Grant D. Murray Michelle Nowlin Pawan G. Patil Douglas N. Rader Stephen E. Roady Shakuntala H. Thilsted Sarah Zoubek 《Ambio》2021,50(5):981
The international development community is off-track from meeting targets for alleviating global malnutrition. Meanwhile, there is growing consensus across scientific disciplines that fish plays a crucial role in food and nutrition security. However, this ‘fish as food’ perspective has yet to translate into policy and development funding priorities. We argue that the traditional framing of fish as a natural resource emphasizes economic development and biodiversity conservation objectives, whereas situating fish within a food systems perspective can lead to innovative policies and investments that promote nutrition-sensitive and socially equitable capture fisheries and aquaculture. This paper highlights four pillars of research needs and policy directions toward this end. Ultimately, recognizing and working to enhance the role of fish in alleviating hunger and malnutrition can provide an additional long-term development incentive, beyond revenue generation and biodiversity conservation, for governments, international development organizations, and society more broadly to invest in the sustainability of capture fisheries and aquaculture.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01451-4) contains supplementary material, which is available to authorized users. 相似文献
426.
Luo Yaowen Yan Jianguo McClure Stephen 《Environmental science and pollution research international》2021,28(6):6587-6599
Environmental Science and Pollution Research - The COVID-19 outbreak has become a global pandemic. The spatial variation in the environmental, health, socioeconomic, and demographic risk factors of... 相似文献
427.
Zhu Feng Chen Lan Qian Zhengmin Liao Yuxue Zhang Zhen McMillin Stephen Edward Wang Xiaojie Lin Hualiang 《Environmental science and pollution research international》2021,28(28):37195-37203
Environmental Science and Pollution Research - There are relatively few studies that focus on the health effects of exposure to size-specific particles on respiratory mortality in China. We aimed... 相似文献
428.
Duarte-Guardia Sandra Peri Pablo L. Amelung Wulf Sheil Douglas Laffan Shawn W. Borchard Nils Bird Michael I. Dieleman Wouter Pepper David A. Zutta Brian Jobbagy Esteban Silva Lucas C. R. Bonser Stephen P. Berhongaray Gonzalo Piñeiro Gervasio Martinez Maria-Jose Cowie Annette L. Ladd Brenton 《Mitigation and Adaptation Strategies for Global Change》2019,24(3):355-372
Mitigation and Adaptation Strategies for Global Change - Soils hold the largest pool of organic carbon (C) on Earth; yet, soil organic carbon (SOC) reservoirs are not well represented in climate... 相似文献
429.
Anton Eitzinger Peter Läderach Beatriz Rodriguez Myles Fisher Stephen Beebe Kai Sonder Axel Schmidt 《Mitigation and Adaptation Strategies for Global Change》2017,22(5):743-760
Drybeans (Phaseolus vulgaris L.) are an important subsistence crop in Central America. Future climate change may threaten drybean production and jeopardize smallholder farmers’ food security. We estimated yield changes in drybeans due to changing climate in these countries using downscaled data from global circulation models (GCMs) in El Salvador, Guatemala, Honduras, and Nicaragua. We generated daily weather data, which we used in the Decision Support System for Agrotechnology Transfer (DSSAT) drybean submodel. We compared different cultivars, soils, and fertilizer options in three planting seasons. We analyzed the simulated yields to spatially classify high-impact spots of climate change across the four countries. The results show a corridor of reduced yields from Lake Nicaragua to central Honduras (10–38 % decrease). Yields increased in the Guatemalan highlands, towards the Atlantic coast, and in southern Nicaragua (10–41 % increase). Some farmers will be able to adapt to climate change, but others will have to change crops, which will require external support. Research institutions will need to devise technologies that allow farmers to adapt and provide policy makers with feasible strategies to implement them. 相似文献
430.