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181.
Pieter Johannes Verkerk Giuliana Zanchi Marcus Lindner 《Environmental management》2014,53(6):1085-1094
Forest protection is one of the main measures to prevent loss of biological and landscape diversity. This study aimed to assess to what extent forests are currently protected and how felling restrictions affect the potential annual wood supply within 27 European Union member states, Norway, and Switzerland and to discuss trade-offs between intensified use of forest biomass and forest protection efforts. Protected forests covered 33 million ha (20 % of total forest area) in 2005, of which 16 million ha was protected for biodiversity and the remaining area for landscape diversity. Within the protected areas, on average 48 % of the volume cannot be harvested in forests protected for biodiversity and 40 % in forests protected for landscapes. Consequently, 73 million m3 (10 % of the annual theoretical potential supply from the total forest area) of wood cannot be felled from the protected forests in Europe. Protected forests do not necessarily affect wood supply given the current demand for wood in Europe. However, if demand for wood from European forests for material and energy use significantly increases, the impact of existing protected forest networks may become significant after all. On the other hand, wood harvesting is allowed to a fair extent in many protected areas. Hence, the question could be raised whether biodiversity and landscape diversity within designated areas are sufficiently protected. Careful planning is required to accommodate both the protection of biological and landscape diversity and demand for wood, while not forgetting all other services that forests provide. 相似文献
182.
Birgit K. Boogaard Bettina B. Bock Simon J. Oosting Johannes S. C. Wiskerke Akke J. van der Zijpp 《Journal of Agricultural and Environmental Ethics》2011,24(3):259-282
Society’s relationship with modern animal farming is an ambivalent one: on the one hand there is rising criticism about modern
animal farming; on the other hand people appreciate certain aspects of it, such as increased food safety and low food prices.
This ambivalence reflects the two faces of modernity: the negative (exploitation of nature and loss of traditions) and the
positive (progress, convenience, and efficiency). This article draws on a national survey carried out in the Netherlands that
aimed at gaining a deeper understanding about the acceptance of modern dairy farming in Dutch society. People take two dimensions
into account when evaluating different aspects of modern dairy farming: (1) the way living beings are used for production
and (2) the way a dairy farm functions as a business. In both these dimensions people appeared to adopt cautious opinions:
most people preferred relatively traditional and natural farms and were concerned about the use of nature and treatment of
animals in modern production—although this did not imply an outright rejection of modern animal farming. The study also looked
for (and sought to explain) differences of opinion between social groups. Besides socio-demographic factors such as age and
gender, farming experience and value-orientation (such as socially minded and professional) appeared to be important variables.
The values and convictions within modern society can help to explain why some people are greatly concerned about animal welfare
while some show less concern. This diversity also helps to explain why general information campaigns are quite ineffective
in allaying concerns about modern animal farming. 相似文献
183.
Elie Gaget Alison Johnston Diego Pavón-Jordán Aleksi S. Lehikoinen Brett K. Sandercock Alaaeldin Soultan Luka Božič Preben Clausen Koen Devos Cristi Domsa Vitor Encarnação Sándor Faragó Niamh Fitzgerald Teresa Frost Clemence Gaudard Lívia Gosztonyi Fredrik Haas Menno Hornman Tom Langendoen Christina Ieronymidou Leho Luigujõe Włodzimierz Meissner Tibor Mikuska Blas Molina Zuzana Musilová Jean-Yves Paquet Nicky Petkov Danae Portolou Jozef Ridzoň Laimonas Sniauksta Antra Stīpniece Norbert Teufelbauer Johannes Wahl Marco Zenatello Jon E. Brommer 《Conservation biology》2022,36(4):e13877
Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds. 相似文献
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This article describes the gasification of polyethylene–wood mixtures to form syngas (H2 and CO) with the aim of feedstock recycling via direct fermentation of syngas to ethanol. The aim was to determine the effects
of four process parameters on process properties that give insight into the efficiency of gasification in general, and particularly
into the optimum gasification conditions for the production of ethanol by fermentation of producer gas. Gasification experiments
(fluidized bed, 800°–950°C) were done under different conditions to optimize the composition of syngas suitable for fermentation
purposes. The data obtained were used for statistical analysis and modeling. In this way, the effect of each parameter on
the process properties was determined and the model was used to predict the optimum gasification conditions. The parameters
varied during the experiment were gasification temperature, equivalence ratio, the ratio of plastic to wood in the feed, and
the amount of steam added to the process. The response models obtained proved to be statistically significant in the experimental
domain. The optimum gasification conditions for maximization of carbon monoxide and hydrogen production were identified. The
conditions are: temperature 900°C, equivalence ratio 0.15, amount of plastic in the feed 0.11 g/g feed, and amount of steam
added 0.42 g/g feed. These optimum conditions are at the edge of the present experimental domain. The maximum combined CO
and H2 efficiency was 42%, and for the maximum yield of CO and H2 it is necessary to minimize the polyethylene content, minimize the added steam and the equivalence ratio, and maximize temperature. 相似文献
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