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71.
《Mammalian Biology》2014,79(3):176-182
Rapid changes in agricultural landscape structure and composition affect many different farmland biotas, including carnivores, which are a key element of ecosystem stability, yet little is known about their distribution and habitat use. In this study, we evaluated how habitat characteristics on two different spatial scales (local and landscape scale) affected the forest-edge utilization by small and medium-sized carnivores in fragmented central European farmland. Based on an indirect method for detecting carnivores (scent stations), we sampled 212 forest fragments of different sizes (1–7864 ha) during April to May from 2006 to 2009. Our results indicate that carnivore utilization of forest-edge habitats was driven by landscape rather than local characteristics even though the overall extent of explained variation was small. The most important factors that determined response of the carnivore community were the area of farmland and that of urban land on a landscape scale. The corridor connectivity between small forest fragments and other spatial elements played a crucial role in the occurrence of red fox. Our results suggest that comprehensive studies on multi-species carnivore assemblage using scent station might be useful in evaluating species-specific response to habitat characteristics, especially if large numbers of stations visited by carnivores are available. 相似文献
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73.
The unique physicochemical properties of (2D) nanomaterials make them well‐suited for use in sustainable energy applications. Many of these materials can be further improved with vacancy engineering. This review details recent progress in the vacancy engineering of ultrathin 2D nanomaterials. For clarity, it mainly focuses on various ultrathin 2D materials in three categories: Xa&XaYb‐, MaXb‐, or MaXbYc‐structured materials. Recently developed vacancies in different types of ultrathin 2D materials, as well as their preparation and characterization, are described. Emphasis is placed on the potential electrochemical energy storage and conversion applications of these materials. This review considers the relationship between vacancy properties and material categories of various ultrathin 2D materials in terms of application requirements, preparation, and characterization techniques. The challenges and future outlook of this promising field are summarized. 相似文献
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《Animal : an international journal of animal bioscience》2020,14(12):2642-2651
Utilization of low-input feed resources rich in plant bioactive compounds is a promising strategy for modulating the fatty acid profile in ruminant products. They manipulate microbes involved in rumen biohydrogenation and increase the accumulation of desirable fatty acids at the tissue level. Therefore, the present study was undertaken to assess the effect of dietary supplementation of aniseed straw and eucalyptus leaves on growth performance, carcass traits and fatty acid profile of finisher lambs. Thirty-six Malpura hogget were divided into three treatment groups of 12 each, reared individually in pen (1.6 m × 1.1 m) and fed ad libitum complete feed blocks made up of 55 parts concentrate, 5 parts molasses and 40 parts roughage. Roughage in control (Con) was 20 parts each of ardu (Ailanthus excelsa) leaves and oat (Avena sativa) straw. In test diets, that is, Con-as and Con-el, 10% aniseed (Pimpinella anisum) straw and Eucalyptus rudis leaves, respectively, were added by replacing 5% each of oat straw and eucalyptus leaves. The lambs were weighed weekly; and at the end of 3 months of feeding trial, the lambs were slaughtered to study the carcass traits, composition and product evaluation. Average daily gain (ADG) and DM intake (DMI) was higher (P < 0.05) in Con-as compared to Con and Con-el, while ADG and feed conversion ratio decreased (P < 0.05) by 29.4% and 36.4%, respectively, in Con-el compared to Con. Carcass traits showed lower (P < 0.05) loin eye area and chilling loss in the Con-el group compared to the Con-as and Con, and the total carcass fat compared to Con-as. However, the keeping quality of meat improved in both Con-as and Con-el which was reflected by lower (P < 0.05) thiobarbituric acid-reactive substances values. Nuggets prepared from Con and Con-as meat had superior (P < 0.05) sensory attributes with an overall palatability. Fatty acid profile of longissimus thoracis muscle showed lower (P < 0.05) atherogenic and thrombogenic indices in Con-as and higher (P < 0.05) in Con-el group. Moreover, in Con-as group, the proportion of C16:0 was lower (P < 0.05) and C18:3n-3 was higher (P < 0.05), but no effect was observed on the amount of conjugated linoleic acid (CLA; C18:2 c9t11). In case of adipose tissue, the content of CLA was higher (P < 0.05), and the ratio of n-6:n-3 was more nearer to desirable levels in Con-as group. Therefore, it can be concluded that aniseed straw is a promising feed supplement compared to eucalyptus leaves for improving meat quality and fatty acid profile in lambs. 相似文献
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Matthias Albrecht David Kleijn Neal M. Williams Matthias Tschumi Brett R. Blaauw Riccardo Bommarco Alistair J. Campbell Matteo Dainese Francis A. Drummond Martin H. Entling Dominik Ganser G. Arjen de Groot Dave Goulson Heather Grab Hannah Hamilton Felix Herzog Rufus Isaacs Katja Jacot Philippe Jeanneret Mattias Jonsson Eva Knop Claire Kremen Douglas A. Landis Gregory M. Loeb Lorenzo Marini Megan McKerchar Lora Morandin Sonja C. Pfister Simon G. Potts Maj Rundlf Hillary Sardias Amber Sciligo Carsten Thies Teja Tscharntke Eric Venturini Eve Veromann Ines M.G. Vollhardt Felix Wckers Kimiora Ward Andrew Wilby Megan Woltz Steve Wratten Louis Sutter 《Ecology letters》2020,23(10):1488-1498
Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future. 相似文献
78.
Food action plans in many global cities articulate interest in multiple objectives including reducing in‐ and trans‐boundary environmental impacts (water, land, greenhouse gas (GHG)). However, there exist few standardized analytical tools to compare food system characteristics and actions across cities and countries to assess trade‐offs between multiple objectives (i.e., health, equity) with environmental outcomes. This paper demonstrates a streamlined model applied for analysis of four cities with varying characteristics across the United States and India, to quantify system‐wide water, energy/GHG, and land impacts associated with multiple food system actions to address health, equity, and environment. Baseline diet analysis finds key differences between countries in terms of meat consumption (Delhi 4; Pondicherry 16; United States 59, kg/capita/year), and environmental impact of processing of the average diet (21%, 19%, <1%, <1% of community‐wide GHG‐emissions for New York, Minneapolis, Delhi, and Pondicherry). Analysis of supply chains finds city average distance (food‐miles) varies (Delhi 420; Pondicherry 200; United States average 1,640 km/t‐food) and the sensitivity of GHG emissions of food demand to spatial variability of energy intensity of irrigation is greater in Indian than US cities. Analysis also finds greater pre‐consumer waste in India versus larger post‐consumer accumulations in the United States. Despite these differences in food system characteristics, food waste management and diet change consistently emerge as key strategies. Among diet scenarios, all vegetarian diets are not found equal in terms of environmental benefit, with the US Government's recommended vegetarian diet resulting in less benefit than other more focused targeted diet changes. 相似文献
79.
《Microbes and infection / Institut Pasteur》2020,22(4-5):221-225
SARS-CoV-2, the newly identified human coronavirus causing severe pneumonia pandemic, was probably originated from Chinese horseshoe bats. However, direct transmission of the virus from bats to humans is unlikely due to lack of direct contact, implying the existence of unknown intermediate hosts. Angiotensin converting enzyme 2 (ACE2) is the receptor of SARS-CoV-2, but only ACE2s of certain species can be utilized by SARS-CoV-2. Here, we evaluated and ranked the receptor-utilizing capability of ACE2s from various species by phylogenetic clustering and sequence alignment with the currently known ACE2s utilized by SARS-CoV-2. As a result, we predicted that SARS-CoV-2 tends to utilize ACE2s of various mammals, except murines, and some birds, such as pigeon. This prediction may help to screen the intermediate hosts of SARS-CoV-2. 相似文献
80.
基于组合评价法的湖南省农业可持续发展区域分异 总被引:1,自引:0,他引:1
从农业资源与环境、农业生产与经济、农业人口与社会3个评价维度构建了区域农业可持续发展指标体系, 运用主成分分析法、熵值法、模糊Borda法、因子分析法及聚类分析法和GIS技术, 通过组合评价方法定量研究湖南省农业可持续发展区域分异现状。结果表明: 湖南省农业可持续发展在区域上总体呈现出不平衡的发展状态, 农业可持续发展综合水平以长株潭城市群为核心, 由东至西递减; 农业人口与社会可持续发展水平南北低中部高, 东部强西部弱; 农业生产与经济可持续发展水平围绕湘北洞庭湖农业区和湘南农业综合区向外围递减; 农业资源与环境可持续发展水平表现为一横两纵优势带和南北两个落后圈。 相似文献