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21.
Werner Theobald 《Environmental Sciences Europe》2003,15(4):262-272
Environmental assessment is a domain of economic, legal and natural sciences. Emotional aspects of environmental assessment are widely undiscussed. However, the consideration of the emotional relationship with nature is an important prerequisite for the acceptance of nature conservation. In connection with the current discussion on aspects of environmental ethics and aesthetics of nature, philosophy has been considering the emotional relationship with nature. However, the analysis of these philosophical approaches shows that they are not able to reconstruct that relationship appropriately. This paper tries to give a new answer. It interprets the emotional relationship with nature as a relic of mythic thinking. 相似文献
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W. Theobald 《Environmental Sciences Europe》2009,21(5):419-432
In Germany, genetic engineering is a very controversial technology. Politicians request more functional discussion and rational assessment. This paper discusses a prominent assessment model of GM-Technology. It examines the methodological structure of the model and the validity of its arguments, in particular how the norms used in the model are developed. 相似文献
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The dual goals of the Organic Act of 1916 and Wilderness Act of 1964 are to protect natural resources and provide quality
visitor experiences. Park managers need metrics of trail conditions to protect park resources and quality of visitor experiences.
A few methods of sampling design for trails have been developed. Here, we describe a relatively new method, spatially balanced
sampling, and compare it to systematic sampling. We evaluated the efficiency of sampling designs to measure recreation-related
impacts in Rocky Mountain National Park. This study addressed two objectives: first, it compared estimates of trail conditions
from data collected from systematic versus spatially balanced sampling data; second, it examined the relationship between
sampling precision and sampling efficiency. No statistically significant differences in trail condition were found between
the 100-m interval and the spatially balanced datasets. The spatially balanced probability-based dataset was found to be a
good estimate of trail conditions when analyses were conducted with fewer sample points. Moreover, spatially balanced probability-based
sampling is flexible and allows additional sample points to be added to a sample. 相似文献
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We conducted an experiment to quantify the accuracy of methods based on n-alkanes and long-chain fatty alcohols for determining the diet composition of animals grazing complex swards. We cut forage from two indigenous vegetation communities, a Molinia caerulea-dominated grassland and a Calluna vulgaris-dominated dwarf-shrub community, and offered it to mature ewes in different ratios in a zero-grazing experiment. Nine dietary categories were identified within the forage offered: Molinia caerulea, Festuca spp., Juncus effusus, Carex spp., Calluna vulgaris, Erica tetralix, Vaccinium myrtillus, and dead grass. Samples of each of these categories together with fecal samples from each individual animal were analyzed for n-alkane and long-chain fatty alcohol concentrations. We analyzed the data using optimization software to minimize the sum of squares differences in the proportional profiles of n-alkanes and fatty alcohols in the diet and feces. Different combinations of n-alkane and fatty alcohols were investigated to assess which gave the most accurate measures of diet composition from the fecal profile. The most accurate estimates were obtained using combinations of the n-alkanes C25, C29, C31, and C33 and the long-chain fatty alcohols 1-C24-ol, 1-C28-ol, and 1-C30-ol, and these gave values for Lin's concordance correlation coefficient between estimated and actual values of >0.98. Our results demonstrate that n-alkanes and long-chain fatty alcohols can be used to estimate several components within the diet of animals grazing complex swards. Diet composition information obtained using this methodology has wide-ranging applications in terms of the assessment of the impact of grazing animals on particular ecosystems or the quantification of nutrient supply to the animal from different selection choices. 相似文献
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Brett G. Dickson Christine M. Albano Ranjan Anantharaman Paul Beier Joe Fargione Tabitha A. Graves Miranda E. Gray Kimberly R. Hall Josh J. Lawler Paul B. Leonard Caitlin E. Littlefield Meredith L. McClure John Novembre Carrie A. Schloss Nathan H. Schumaker Viral B. Shah David M. Theobald 《Conservation biology》2019,33(2):239-249
Conservation practitioners have long recognized ecological connectivity as a global priority for preserving biodiversity and ecosystem function. In the early years of conservation science, ecologists extended principles of island biogeography to assess connectivity based on source patch proximity and other metrics derived from binary maps of habitat. From 2006 to 2008, the late Brad McRae introduced circuit theory as an alternative approach to model gene flow and the dispersal or movement routes of organisms. He posited concepts and metrics from electrical circuit theory as a robust way to quantify movement across multiple possible paths in a landscape, not just a single least-cost path or corridor. Circuit theory offers many theoretical, conceptual, and practical linkages to conservation science. We reviewed 459 recent studies citing circuit theory or the open-source software Circuitscape. We focused on applications of circuit theory to the science and practice of connectivity conservation, including topics in landscape and population genetics, movement and dispersal paths of organisms, anthropogenic barriers to connectivity, fire behavior, water flow, and ecosystem services. Circuit theory is likely to have an effect on conservation science and practitioners through improved insights into landscape dynamics, animal movement, and habitat-use studies and through the development of new software tools for data analysis and visualization. The influence of circuit theory on conservation comes from the theoretical basis and elegance of the approach and the powerful collaborations and active user community that have emerged. Circuit theory provides a springboard for ecological understanding and will remain an important conservation tool for researchers and practitioners around the globe. 相似文献
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Duretz S Drouet JL Durand P Hutchings NJ Theobald MR Salmon-Monviola J Dragosits U Maury O Sutton MA Cellier P 《Environmental pollution (Barking, Essex : 1987)》2011,159(11):3162-3170
Modelling nitrogen transfer and transformation at the landscape scale is relevant to estimate the mobility of the reactive forms of nitrogen (Nr) and the associated threats to the environment. Here we describe the development of a spatially and temporally explicit model to integrate Nr transfer and transformation at the landscape scale. The model couples four existing models, to simulate atmospheric, farm, agro-ecosystem and hydrological Nr fluxes and transformations within a landscape. Simulations were carried out on a theoretical landscape consisting of pig-crop farms interspersed with unmanaged ecosystems. Simulation results illustrated the effect of spatial interactions between landscape elements on Nr fluxes and losses to the environment. More than 10% of the total N2O emissions were due to indirect emissions. The nitrogen budgets and transformations of the unmanaged ecosystems varied considerably, depending on their location within the landscape. The model represents a new tool for assessing the effect of changes in landscape structure on Nr fluxes. 相似文献
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Occurrence of perfluorinated organic acids in the North and Baltic Seas. Part 2: distribution in sediments 总被引:1,自引:0,他引:1
Theobald N Caliebe C Gerwinski W Hühnerfuss H Lepom P 《Environmental science and pollution research international》2012,19(2):313-324
Purpose
The distribution of polar perfluorinated compounds (PFCs) in sea water of the North and Baltic Seas has been described in part 1 of this study. In part 2, their occurrence in sediments is described in order to further investigate their distribution routes and possible sinks. 相似文献30.