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101.
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
102.
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104.
Ailemys Curbelo Axel Mancebo Tatiana Molier María E. Arteaga Consuelo González Raiden Grandía 《毒物与环境化学》2013,95(4):691-699
Biological control agents have become a useful alternative for the reduction of the use of chemical insecticides. LABIOFAM (Cuba) is developing a new formulation of a biolarvicide that possesses as active biological agent Bacillus thuringiensis var israelensis serotype H14. In order to evaluate the genotoxicity of this new formulation, an in vivo battery test was used: micronucleus (MN), chromosome aberrations (CAs), and sperm morphology (SM) assays. A dose of 6.45?×?108 spores was administered per animal via oral administration. Bone marrow cells were collected 24?h after a two day treatment for the MN assay, and 24?h after a unique treatment for the CA assay, using cyclophosphamide as the positive control. Sperm cells were collected at 5 weeks from the first of five administrations for the SM test, using acrylamide as positive control. Bacillus thuringiensis var israelensis serotype H14 failed to show either a significative increase of micronucleated polychromatic erythrocytes, chromosomal aberrations, or sperm abnormalities. Acute oral administration of a high dose of Bacillus thuringiensis var israelensis serotype H14 did not produce mutagenic effects in bone marrow or sperm cells. 相似文献
105.
Soils are a key component of the terrestrial carbon cycle as they contain the majority of terrestrial carbon. Soil microorganisms mainly control the accumulation and loss of this carbon. However, traditional concepts of soil carbon stabilisation failed so far to account for environmental and energetic constraints of microorganisms. Here, we demonstrate for the first time that these biological limitations might have the overall control on soil carbon stability. In a long-term experiment, we incubated 13C-labelled compost with natural soils at various soil carbon concentrations. Unexpectedly, we found that soil carbon turnover decreased with lower carbon concentration. We developed a conceptual model that explained these observations. In this model, two types of particles were submitted to random walk movement in the soil profile: soil organic matter substrate and microbial decomposers. Soil carbon turnover depended only on the likelihood of a decomposer particle to meet a substrate particle; in consequence, carbon turnover decreased with lower carbon concentration, like observed in the experiment. This conceptual model was able to simulate realistic depth profiles of soil carbon and soil carbon age. Our results, which are simply based on the application of a two-step kinetic, unmystify the stability of soil carbon and suggest that observations like high carbon ages in subsoil, stability of carbon in fallows and priming of soil carbon might be simply explained by the probability to be decomposed. 相似文献
106.
Axel Wenblad 《生态毒理学报》2004,26(2):70-71
Skanska公司是世界上第二大建筑公司.它建造家庭住宅、商业建筑(例如,办公室、大型购物中心和旅馆)以及运输基本设施,包括道路、隧道与桥梁.我们的产品和服务影响着发达与发展中国家中许多人的生活,也影响工地周围的人民(例如,由于交通拥挤和产生噪音和灰尘). 相似文献
107.
Reed F. Noss Jennifer M. Cartwright Dwayne Estes Theo Witsell Gregg Elliott Daniel Adams Matthew Albrecht Ryan Boyles Patrick Comer Chris Doffitt Don Faber-Langendoen JoVonn Hill William C. Hunter Wesley M. Knapp Michael E. Marshall Jason Singhurst Christopher Tracey Jeffrey Walck Alan Weakley 《Conservation biology》2021,35(6):1715-1724
Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs. Article impact statement: Species status assessments can be improved by an ecosystem-based approach that groups imperiled species by shared habitats and threats. 相似文献
108.
António O. Soares Danny Haelewaters Olga M. C. C. Ameixa Isabel Borges Peter M. J. Brown Pedro Cardoso Michiel D. de Groot Edward W. Evans Audrey A. Grez Axel Hochkirch Milada Holecová Alois Honěk Ján Kulfan Ana I. Lillebø Zdenka Martinková J. P. Michaud Oldřich Nedvěd Omkar Helen E. Roy Swati Saxena Apoorva Shandilya Arnaud Sentis Jiri Skuhrovec Sandra Viglášová Peter Zach Tania Zaviezo John E. Losey 《Conservation biology》2023,37(1):e13965
Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations. 相似文献
109.
Cai M Xie Z Möller A Yin Z Huang P Cai M Yang H Sturm R He J Ebinghaus R 《Chemosphere》2012,87(9):989-997
Neutral polyfluorinated alkyl substances (PFASs) were measured in high-volume air samples collected on board the research vessel Snow Dragon during the 4th Chinese National Arctic Expedition from the Japan Sea to the Arctic Ocean in 2010. Four volatile and semi-volatile PFASs (fluorotelomer alcohols (FTOHs), fluorotelomer acids (FTAs), perfluoroalkyl sulfonamides (FASAs), and sulfonamidoethanols (FASEs)) were analyzed respectively in the gas and particle phases. FTOHs were the dominant PFASs in the gas phase (61-358 pg m−3), followed by FTAs (5.2-47.9 pg m−3), FASEs (1.9-15.0 pg m−3), and FASAs (0.5-2.1 pg m−3). In the particle phase, the dominant PFAS class was FTOHs (1.0-9.9 pg m−3). The particle-associated fraction followed the general trend of FASEs > FASAs > FTOHs. Compared with other atmospheric PFAS measurements, the ranges of concentrations of ∑FTOH in this study were similar to those reported from Toronto, north America (urban), the northeast Atlantic Ocean, and northern Germany. Significant correlations between FASEs in the gas phase and ambient air temperature indicate that cold surfaces such as sea-ice, snowpack, and surface seawater influence atmospheric FASEs. 相似文献
110.
Fortuna AM Honeycutt CW Vandemark G Griffin TS Larkin RP He Z Wienhold BJ Sistani KR Albrecht SL Woodbury BL Torbert HA Powell JM Hubbard RK Eigenberg RA Wright RJ Alldredge JR Harsh JB 《Journal of environmental quality》2012,41(1):262-272
Soil biotic and abiotic factors strongly influence nitrogen (N) availability and increases in nitrification rates associated with the application of manure. In this study, we examine the effects of edaphic properties and a dairy (Bos taurus) slurry amendment on N availability, nitrification rates and nitrifier communities. Soils of variable texture and clay mineralogy were collected from six USDA-ARS research sites and incubated for 28 d with and without dairy slurry applied at a rate of ~300 kg N ha(-1). Periodically, subsamples were removed for analyses of 2 M KCl extractable N and nitrification potential, as well as gene copy numbers of ammonia-oxidizing bacteria (AOB) and archaea (AOA). Spearman coefficients for nitrification potentials and AOB copy number were positively correlated with total soil C, total soil N, cation exchange capacity, and clay mineralogy in treatments with and without slurry application. Our data show that the quantity and type of clay minerals present in a soil affect nitrifier populations, nitrification rates, and the release of inorganic N. Nitrogen mineralization, nitrification potentials, and edaphic properties were positively correlated with AOB gene copy numbers. On average, AOA gene copy numbers were an order of magnitude lower than those of AOB across the six soils and did not increase with slurry application. Our research suggests that the two nitrifier communities overlap but have different optimum environmental conditions for growth and activity that are partly determined by the interaction of manure-derived ammonium with soil properties. 相似文献