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101.
Assessments of large-scale changes in habitat are a priority for management and conservation. Traditional approaches use land use and land cover data (LULC) that focus mostly on “structural” properties of landscapes, rather than “functional” properties related to specific ecological processes. Here, we contend that designing functional analyses of LULC can provide important and complementary information to traditional, structural analyses. We substantiate this perspective with an example of functional changes in habitat due to industrial anthropogenic footprints in Alberta’s boreal forest, where there has been little overall forest loss (~ 6% structural change), but high levels of functional change (up to 93% functional change) for species’ habitat, biodiversity, and wildfire ignition. We discuss the methods needed to achieve functional LULC analyses, when they are most appropriate to add to structural assessments, and conclude by providing recommendations for analyses of LULC in a future of increasingly high-resolution, dynamic remote sensing data.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01434-5) contains supplementary material, which is available to authorized users. 相似文献
102.
Per Axel Clausen Cornelius Ken Wilkins Peder Wolkoff Gunnar Damgrd Nielsen 《Environment international》2001,26(7-8)
The airway irritation of a reaction mixture of R-(+)-limonene and ozone was evaluated by a mouse bioassay in which sensory irritation, bronchoconstriction and pulmonary irritation were measured. Significant sensory irritation (33% reduction of mean respiratory rate) was observed by dynamic exposure of the mice, during 30 min, to a ca. 16 s old reaction mixture of ozone and limonene. The initial concentrations were nominally 4 ppm O3 and 48 ppm limonene. After reaction, the residual O3 was <0.03 ppm. Conventional analytical chemical methods were used to measure the formation of readily identified and stable products. Besides the expected products, 1-methyl-4-acetylcyclohexene (AMCH), 3-isopropenyl-6-oxoheptanal (IPOH), formaldehyde and formic acid, autooxidation products of limonene and a series of compounds (i.e., acetone, acrolein and acetic acid), which may or may not be artefacts, were identified. Addition of the sensory irritation effects of the residual reactants and all the identified compounds could not explain the observed sensory irritation effect. This suggests that one or more strong airway irritants were formed. Since limonene is common in the indoor air, and ozone is infiltrated from outdoors and/or produced indoors (e.g., by photocopiers), such oxidation reactions may be relevant for indoor air quality. 相似文献
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Christian Turra Carlos Eduardo de Freitas Vian Flávia Angeli Guisi Nielsen Priscilla Silva Santos Luis Fernando de Freitas Penteado 《Journal of Agricultural and Environmental Ethics》2014,27(4):663-679
This study aims to characterize the different types of certification in the Brazilian citriculture as well as analyze the major changes in the market. The paper also has the objective to discuss how social and environmental factors influence the demand for food certifications and the sustainability and ethics aspects in the field. Therefore, a literature review on the subject was carried out as well as a qualitative research using interviews with certifiers, governmental institutions, farmers, cooperatives and producer associations. The certification is becoming mandatory for those working in foreign markets and for those working nationally; it can be a competitive differential. The organic certification in citriculture shows the highest number of growers. Companies with large areas of citrus and the orange juice processing industry are adhering to this certification in order to maintain themselves competitive in the market. There is an enormous potential of Brazilian citriculture certification, because the certified area is still less than 6 % of the total area. Certification reduces the asymmetry of information and consists of an important step towards sustainability although incapable of solely guaranteeing it. 相似文献
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This paper compares individual (split) and central systems of air-conditioning in a life cycle perspective, taking into account the environmental impacts and resource consumption during resource extraction, material production, production of the air-conditioning units, their use, disposal and recycling. Life cycle assessment (LCA) is used in conducting this comparison. Central systems have a longer lifetime than individual systems, lower electricity consumption and maintenance requirements during the use phase, and a higher recycling potential during the disposal phase. However, to transfer cool air, central systems use a large quantity of water pipes or air ducts, the production of which contributes significantly to resource use. The LCA study reveals that, on the whole, the central systems generally use less resources than split systems and result in lower environmental impacts. The paper suggests a need for producers of air-conditioners to consider a change from being suppliers of air-conditioning hardware to being suppliers of cool air in order to overcome the initial cost constraints of central systems and realize their environmental and economic improvement potential to the benefit of the environment, and the industry as well as customers. 相似文献
107.
Greta Nielsen 《国际发展与全球生态学杂志》2013,20(4):297-310
Increasing land consumption and loss of biodiversity make it particularly important that protected areas fulfil their function. This, however, is often impaired by insufficient political and financial support. This study investigates how existing protected area management capacities can be used more effectively in a prompt and lasting manner. Therefore, data from protected area management effectiveness evaluations were analysed. Efficient workflows and teamwork were identified to be key capacities for effective management. Simultaneously, deficient financial and social security, lack of incentives and inflexible management structures prevent the productive use of existing capacities. In order to improve the situation, greater attention should be given to intangible assets. Additionally, protected area managers and employees must be enabled to be more self-reliant and self-responsible in order to foster a lasting learning process. 相似文献
108.
Jessica R. Frost Anneke Denda Clive J. Fox Charles A. Jacoby Rolf Koppelmann Morten Holtegaard Nielsen Marsh J. Youngbluth 《Marine Biology》2012,159(2):239-253
The ecology of small, gelatinous zooplankton is not integrated into management of Dogger Bank (54° 00′ N, 3° 25′ E to 55°
35′ N, 2° 20′ E). In pursuit of this goal, gelatinous zooplankton and their potential prey were sampled along a transect across
the bank on June 10–16, 2007. Eleven species of small medusae and ctenophores were collected, with six abundant taxa occurring
in greater numbers below the thermocline and in the shallower, southeastern portion of the bank. There were no statistically
significant diel changes in distribution. In contrast, potential prey were distributed more evenly across the bank and throughout
the water column. Isotopic analyses revealed that gelatinous zooplankton fed on both smaller (100–300 μm) and larger (>300 μm)
mesozooplankton, but also potentially on each other. These ecological insights suggest that small medusae and ctenophores
should be integrated into sustainable management of Dogger Bank. 相似文献
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