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31.
More than 30 years after it was first proposed as a biodiversity conservation strategy, rewilding remains a controversial concept. There is currently little agreement about what the goals of rewilding are, and how these are best achieved, limiting the utility of rewilding in mainstream conservation. Achieving consensus about rewilding requires agreeing about what “wild” means, but many different definitions exist, reflecting the diversity of values in conservation. There are three key debates that must be addressed to find a consensual definition of “wild”: (1) to which extent can people and “wild” nature co-exist?; (2) how much space does “wild” nature need? and (3) what kinds of “wild” nature do we value? Depending on the kinds of “wild” nature rewilding aims to create, rewilding policy will be faced with managing different opportunities and risks for biodiversity and people.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01560-8.  相似文献   
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INTRODUCTION: The most effective means of preventing and controlling occupational injuries, illness, and fatalities is to "design out" hazards and hazardous exposures from the workplace. There is a long history of designing for safety for the general public and to a lesser degree for workers. METHOD: We now have the experience and insight from thoughtful, previous efforts to call for a comprehensive national strategy to implement a Prevention through Design (PtD) Initiative. RESULTS: This paper describes that initiative in terms of four overarching areas where action can be directed: practice, policy, research, and education. To obtain stakeholder input for issues in these four areas and to focus implementation efforts, eight sector divisions of the economy will be addressed. A seven year strategy is envisioned.  相似文献   
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Abstract: Although pollinator declines are a global biodiversity threat, the demography of the western honeybee (Apis mellifera) has not been considered by conservationists because it is biased by the activity of beekeepers. To fill this gap in pollinator decline censuses and to provide a broad picture of the current status of honeybees across their natural range, we used microsatellite genetic markers to estimate colony densities and genetic diversity at different locations in Europe, Africa, and central Asia that had different patterns of land use. Genetic diversity and colony densities were highest in South Africa and lowest in Northern Europe and were correlated with mean annual temperature. Confounding factors not related to climate, however, are also likely to influence genetic diversity and colony densities in honeybee populations. Land use showed a significantly negative influence over genetic diversity and the density of honeybee colonies over all sampling locations. In Europe honeybees sampled in nature reserves had genetic diversity and colony densities similar to those sampled in agricultural landscapes, which suggests that the former are not wild but may have come from managed hives. Other results also support this idea: putative wild bees were rare in our European samples, and the mean estimated density of honeybee colonies on the continent closely resembled the reported mean number of managed hives. Current densities of European honeybee populations are in the same range as those found in the adverse climatic conditions of the Kalahari and Saharan deserts, which suggests that beekeeping activities do not compensate for the loss of wild colonies. Our findings highlight the importance of reconsidering the conservation status of honeybees in Europe and of regarding beekeeping not only as a profitable business for producing honey, but also as an essential component of biodiversity conservation.  相似文献   
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通过对总硬度浓度的测定过程分析,找出影响结果的各个分量,进行测量不确定度的评定,按照计量技术规范,给出标准的表示法。  相似文献   
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Zusammenfassung  Verschiedene Mechanismen in der Abkühlungsphase von Hochtemperaturprozessen führen zur Neubildung von polychlorierten Dibenzo(p) dioxinen (PCDD) und polychlorierten Dibenzofuranen (PCDF) und, unabh?ngig von den jeweiligen Absolutkonzentrationen, zu vergleichbaren PCDD/F-Profilen, also prozentualen Anteilen einzelner Kongenere bzw. Homologengruppen an der Summe der betrachtten 17 Kongenere nach 17. BImSchV bzw. Homologengruppen Tetra-bis Octa CDD/F. Die Charakteristik dieser “Verbrennungs-profile” kann zur Plausibilit?tsprüfung von Messergebnissen sowie zur weitergehenden Deutung und zum Verst?ndnis der ablaufenden Reaktionsmechanismen beitragen. Online-First: 9. M?rz 2000  相似文献   
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The chronological development of environmental pollution in the Western Baltic Sea for the past hundred years was investigated in dated sediment cores. An artificial radionuclide (137Cs), nutrients, heavy metals, chlorinated hydrocarbons (PCB, DDT, Lindane) and plasticizers (phthalate esters) show characteristic distribution patterns within the various cores. They can be related to the production and use of specific chemicals and goods, to emissions associated with the increased combustion of coal parallel to industrialization and —in the case of 137Cs — to emissions associated with atomic weapons tests in the high atmosphere. Characteristic trends in the general development of pollution may be superimposed by specific emissions from local sources.  相似文献   
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The fundamental data requirements for the authorization of plant protection products and the inclusion of active ingredients in Annex I of Council Directive 91/414/EEC are described in the Annexes II and III of the Directive. Definite guidelines concerning investigations with arthropods are partially deficient. The uniform principles for the registration of plant protection products in the Member States described in Annex VI of the directive were primarily developed to assess the effects on the beneficial capacity of arthropods in agriculture. However, the risk for arthopods as an essential part of the environment need to be assessed, too. Hence, the German Federal Environmental Agency has developed a tiered approach to assess the effects of plant protection products on arthopods based on the data requirements of Annex II and III of the Directive 91/414/EEC. The risk is assessed using the effect-concentration evaluated in ecotoxicological tests and the environmental concentration predicted by validated exposure models. To protect non-target species in terrestrial ecosystems assessment factors need to be considered.  相似文献   
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