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61.
Maja Wiprächtiger Melanie Haupt Andreas Froemelt Magdalena Klotz Claudio Beretta Dominik Osterwalder Vanessa Burg Stefanie Hellweg 《Journal of Industrial Ecology》2023,27(1):254-271
Industrial ecology (IE) methodologies, such as input/output or material flow analysis and life cycle assessment (LCA), are often used for the environmental evaluation of circular economy strategies. Up to now, an approach that utilizes these methods in a systematic, integrated framework for a holistic assessment of a geographic region's sustainable circular economy potential has been lacking. The approach developed in this study (IE4CE approach) combines IE methodologies to determine the environmental impact mitigation potential of circular economy strategies for a defined geographic region. The approach foresees five steps. First, input/output analysis helps identify sectors with high environmental impacts. Second, a refined analysis is conducted using material flow and LCA. In step 3, circular strategies are used for scenario design and evaluated in step 4. In step 5, the assessment results are compiled and compared across sectors. The approach was applied to a case study of Switzerland, analyzing 8 sectors and more than 30 scenarios in depth. Carbon capture and storage (CCS) from waste incineration, biogas and cement production, food waste prevention in households, hospitality and production, and the increased recycling of plastics had the highest mitigation potential. Most of the scenarios do not influence each other. One exception is the CCS scenarios: waste avoidance scenarios decrease the reduction potential of CCS. A combination of scenarios from different sectors, including their impact on the CCS scenario potential, led to an environmental impact mitigation potential of 11.9 Mt CO2-eq for 2050, which equals 14% of Switzerland's current consumption-based impacts. 相似文献
62.
Migration is ubiquitous and can strongly shape food webs and ecosystems. Less familiar, however, is that the majority of life cycle, seasonal and diel migrations in nature are partial migrations: only a fraction of the population migrates while the other individuals remain in their resident ecosystem. Here, we demonstrate different impacts of partial migration rendering it fundamental to our understanding of the significance of migration for food web and ecosystem dynamics. First, partial migration affects the spatiotemporal distribution of individuals and the food web and ecosystem-level processes they drive differently than expected under full migration. Second, whether an individual migrates or not is regularly correlated with morphological, physiological, and/or behavioural traits that shape its food-web and ecosystem-level impacts. Third, food web and ecosystem dynamics can drive the fraction of the population migrating, enabling the potential for feedbacks between the causes and consequences of migration within and across ecosystems. These impacts, individually and in combination, can yield unintuitive effects of migration and drive the dynamics, diversity and functions of ecosystems. By presenting the first full integration of partial migration and trophic (meta-)community and (meta-)ecosystem ecology, we provide a roadmap for studying how migration affects and is affected by ecosystem dynamics in a changing world. 相似文献
63.
During mate choice, receivers often assess the magnitude (duration, size, etc.) of signals that vary along a continuum and reflect variation in signaller quality. It is generally assumed that receivers assess this variation linearly, meaning each difference in signalling trait between signallers results in a commensurate change in receiver response. However, increasing evidence shows receivers can respond to signals non-linearly, for example through Weber's Law of proportional processing, where discrimination between stimuli is based on proportional, rather than absolute, differences in magnitude. We quantified mate preferences of female green swordtail fish, Xiphophorus hellerii, for pairs of males differing in body size. Preferences for larger males were better predicted by the proportional difference between males (proportional processing) than the absolute difference (linear processing). This demonstration of proportional processing of a visual signal implies that receiver perception may be an important mechanism selecting against the evolution of ever-larger signalling traits. 相似文献
64.
65.
Alan M. Goldberg John M. Frazier David Brusick Michael S. Dickens Oliver Flint Stephen D. Gettings Richard N. Hill Robert L. Lipnick Kevin J. Renskers June A. Bradlaw Robert A. Scala Bellina Veronesi Sidney Green Neil L. Wilcox Rodger D. Curren 《In vitro cellular & developmental biology. Animal》1993,29(9):688-692
Summary The development and application of in vitro alternatives designed to reduce or replace the use of animals, or to lessen the
distress and discomfort of laboratory animals, is a rapidly developing trend in toxicology. However, at present there is no
formal administrative process to organize, coordinate, or evaluate validation activities. A framework capable of fostering
the validation of new methods is essential for the effective transfer of new technologic developments from the research laboratory
into practical use. This committee has identified four essential validation resources: chemical bank(s), cell and tissue banks,
a data bank, and reference laboratories. The creation of a Scientific Advisory Board composed of experts in the various aspects
and endpoints of toxicity testing, and representing the academic, industrial, and regulatory communities, is recommended.
Test validation acceptance is contingent on broad buy-in by disparate groups in the scientific community—academics, industry,
and government. This is best achieved by early and frequent communication among parties and agreement on common goals. It
is hoped that the creation of a validation infrastructure composed of the elements described in this report will facilitate
scientific acceptance and utilization of alternative methodologies and speed implementation of replacement, reduction, and
refinement alternatives in toxicity testing. 相似文献
66.
IntroductionSeaweeds are a rich source of elements such as iodine, and are also able to accumulate contaminants such as trace elements.MethodsThe aim of this study was to assess the dietary exposure as well as the risk from iodine and trace elements in edible seaweeds for the French population using current consumption data. The contribution of seaweeds to overall dietary exposure to trace elements and iodine was evaluated, and for those substances with minimal contribution to overall dietary exposure, simulations were performed to propose increased maximal limits in seaweeds.ResultsCadmium, inorganic arsenic and mercury in seaweeds were very low contributors to total dietary exposure to these contaminants (0.7 % 1.1 % and 0.1 % on average, respectively). Dietary exposure to lead via seaweed may contribute up to 3.1 % of total dietary exposure. Dietary consumption of iodine via seaweed may contribute up to 33 % of total exposure to iodine, which makes seaweeds the strongest contributor to iodine in diet.DiscussionNew maximal values in seaweeds are proposed for the very low contributors to total dietary exposure: 1 mg/kg dw for cadmium, 10 mg/kg dw for inorganic arsenic and 0.3 mg/kg dw for mercury. 相似文献
67.
海南坡鹿围栏种群动态与食物资源关系的初步分析 总被引:5,自引:0,他引:5
1986年海南省大田国家级自然保护区在境内设立面积为95公顷的围栏,将86只海南坡鹿分隔成一个孤立的种群。经过3个繁殖年度,种群发展到158只。随着种群数量的增加,坡鹿采食植物的种类密度、高度和频率均明显减少,而坡鹿不食的植物种类则明显增加。种群出生率和年度增长率随种群数量增加而逐年降低,而种群死亡率却有增加趋势。种群密度过高产生的拥挤效应和食物资源不足是造成种群出生率和年度增长率下降的主要原因。本文还就保护区应采取的管理措施,提出了相应的建议。 相似文献
68.
Jerome J. Howard 《Journal of Insect Behavior》1993,6(4):441-453
Patterns of resource fidelity, switching, and variation in individual diet were examined in the polyphagous grasshopper Taeniopoda equesforaging in experimental cages over an 11-day period. Ten novel dicots were provided in the cages, but grasshoppers fed primarily on kale (Brassica oleraceavar. acephala),lobelia (Lobelia erinus),pansy (Viola x wittrockiana),and dry bermuda grass (Cynodon dactylon).Grasshoppers showed significant fidelity to a single plant within a meal but tended to eat less of the same plant in the next meal and, in the case of pansy, on the next day. Grasshoppers switched nonrandomly, suggesting that compensatory feeding on complementary resources may have occurred. There was no evidence that behavioral interactions among individuals increased switching rate or lowered fidelity. Overall patterns of resource use varied significantly among grasshoppers during the study, despite frequent switching among resources and a significant tendency to aggregate while feeding. All individuals were polyphagous but differed in relative consumption of available plants. The results suggest that individual grasshoppers express different feeding patterns that are consistent over time and that variation in diet among individual observed in the field may be more than simple sampling error. 相似文献
69.
Samantha G. Robinson Katie M. Walker Henrietta A. Bellman Daniel Gibson Daniel H. Catlin Sarah M. Karpanty Shannon J. Ritter James D. Fraser 《The Journal of wildlife management》2023,87(1):e22325
Population declines of disturbance-dependent species due to suppression of natural disturbances are realized across ecosystems. The piping plover (Charadrius melodus; plover), a disturbance-dependent and conservation-reliant shorebird that nests on sandy beaches and barrier islands on the Atlantic Coast, was listed under the United States Endangered Species Act in 1986. In 2012, Hurricane Sandy landed on Fire and Westhampton islands, barrier island nesting sites for plovers in New York, USA. Hurricane Sandy was a natural disturbance in this system, creating abundant nesting habitat. The number of chicks produced by a pair, or a population, is a direct measure of reproductive output, and gaining a better understanding of productivity and chick behavior following large-scale habitat creation may improve plover habitat management and potentially species persistence. We evaluated the effects of landscape features on habitat selection, behavior, and survival of plover broods using logistic regression, generalized linear mixed effects models, and survival models. Plover broods selected flatter sites with less dense vegetation than available at random. Chick foraging rates were highest in moist substrates and were lower in areas of higher nesting plover density. Chick survival was greater for broods that hatched earlier in the breeding season and increased as chicks aged. Generally, providing access to sites with flatter, moist substrates will likely result in higher quality brood rearing habitat on the landscape. Ultimately, vegetation removal and habitat management may be needed to reduce plover nesting density and ensure sufficient habitat, which may in turn improve plover chick survival. Moreover, sustaining natural landscape disturbances such as those resulting from storms, and not taking actions to prevent hurricane-created overwash, will allow these landscape features to persist. 相似文献
70.
《Revista espa?ola de geriatría y gerontología》2023,58(1):35-42
Last decade, the Government of Catalonia have urged an integrated care strategy for planning the care model to older populations living with frailty, multimorbidity and advanced illnesses. Based on international evidence that was reviewed by a group of experts from the Catalan Society of Gerontology and Geriatrics, we summarised some recommendation to adapt hospital-at-home care to older populations in our system. We defined Comprehensive Geriatric Assessment (CGA) hospital-at-home (HaH) as a specialised home hospitalisation service formed by interdisciplinary teams, characterised by using the clinical methodology of CGA, and by adapting geriatric units’ protocols for the provision of person-centred care at home. Main benefits of CGA-HaH in these populations are: response to heath crises according to individualised care plans based on the situational diagnosis carried out by Primary Care teams; provision of a comprehensive health and social approach tailored to the complexity of cases and situations; and adaptation of multipurpose hospitalisation, by working on different person-centred care, aspects, such as caregivers support on care provision, focusing on function or home adaptation. 相似文献