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1.
The aim of this article is to further our understanding of the “GM is unnatural” view, and of the critical response to it. While many people have been reported to hold the view that GM is unnatural, many policy-makers and their advisors have suggested that the view must be ignored or rejected, and that there are scientific reasons for doing so. Three “typical” examples of ways in which the “GM is unnatural” view has been treated by UK policy-makers and their advisors are explored. These are the Government’s position (DEFRA Report), the account of the Nuffield Council on Bioethics, and the position of Nigel Halford, a scientist with an advisory role to the Government. I show that their accounts fail to mount a convincing critique. Then, I draw on an empirical research project held during  2003–2004 at the University of Newcastle-upon-Tyne in the north east of England. Scientists met with non-scientists in a range of facilitated one-to-one conversations (“exchanges”) on various environmental issues, one of which was on GM. Our findings show that some scientists who rejected the “GM is unnatural” view struggled to do so consistently. Their struggle is interpreted in terms of a conflict between a so-called “scientific” worldview, and a different worldview that underlies the concerns of those who held the “GM is unnatural” view. This worldview is explored further by an examination of their concerns. What distinguishes this worldview from the “scientific” worldview is that the instrumentalization of the nonhuman world is questioned to a larger extent. I conclude that, because the underlying concerns of those who held the “GM is unnatural” view were not with GM as such, yet with a worldview that was considered to be problematic, and of which many GM applications were held to be expressions, policy-makers and their advisors should reflect on the critical worldview of those who claim that GM is unnatural if they want to engage seriously with their concerns.  相似文献   

2.
The pulp and paper industry is placed in a unique position as biomass used as feedstock is now in increasingly high demand from the energy sector. Increased demand for biomass increases pressure on the availability of this resource, which might strengthen the need for recycling of paper. In this study, we calculate the energy use and carbon dioxide emissions for paper production from three pulp types. Increased recycling enables an increase in biomass availability and reduces life-cycle energy use and carbon dioxide emissions. Recovered paper as feedstock leads to lowest energy use (22 GJ/t) and CO2 emissions (−1100 kg CO2/t) when biomass not used for paper production is assumed to be converted into bio-energy. Large differences exist between paper grades in e.g. electricity and heat use during production, fibre furnish, filler content and recyclability. We found large variation in energy use over the life-cycle of different grades. However, in all paper grades, life-cycle energy use decreases with increased recycling rates and increased use of recovered fibres. The average life-cycle energy use of the paper mix produced in The Netherlands, where the recycling rate is approximately 75%, is about 14 GJ/t. This equals CO2 savings of about 1 t CO2/t paper if no recycled fibres would be used.  相似文献   

3.
There is a consensus that Marine Protected Area (MPA) performance needs regular evaluation against clear criteria, incorporating counterfactual comparisons of ecological and socio-economic performance. However, these evaluations are scarce at the global level. We compiled self-reports from managers and researchers of 78 coral reef-based MPAs world-wide, on the conservation and welfare improvements that their MPAs provide. We developed a suite of performance measures including fulfilment of design and management criteria, achievement of aims, the cessation of banned or destructive activities, change in threats, and measurable ecological and socio-economic changes in outcomes, which we evaluated with respect to the MPA’s age, geographical location and main aims. The sample was found to be broadly representative of MPAs generally, and suggests that many MPAs do not achieve certain fundamental aims including improvements in coral cover over time (in 25% of MPAs), and conflict reduction (in 25%). However, the large majority demonstrated improvements in terms of slowing coral loss, reducing destructive uses and increasing tourism and local employment, despite many being small, underfunded and facing multiple large scale threats beyond the control of managers. However spatial comparisons suggest that in some regions MPAs are simply mirroring outside changes, with demonstrates the importance of testing for additionality. MPA benefits do not appear to increase linearly over time. In combination with other management efforts and regulations, especially those relating to large scale threat reduction and targeted fisheries and conflict resolution instruments, MPAs are an important tool to achieve coral reef conservation globally. Given greater resources and changes which incorporate best available science, such as larger MPAs and no-take areas, networks and reduced user pressure, it is likely that performance could further be enhanced. Performance evaluation should test for the generation of additional ecological and socio-economic improvements over time and compared to unmanaged areas as part of an adaptive management regime.  相似文献   

4.
Hancock, Gregory S., Jonathan W. Holley, and Randolph M. Chambers, 2010. A Field-Based Evaluation of Wet Retention Ponds: How Effective Are Ponds at Water Quantity Control? Journal of the American Water Resources Association (JAWRA) 46(6):1145–1158. DOI: 10.1111/j.1752-1688.2010.00481.x Abstract: Wet retention ponds are widely used structural stormwater best management practices (BMPs) with the primary goals of reducing peak flows and extending flow duration. Despite widespread use, few field-based studies have evaluated the success of wet retention ponds at meeting these goals. We determined pond elevation, flow rate, and pond volume over four years in five suburban watersheds in James City County, Virginia. We selected five ponds designed under regulations requiring a 24 hour inflow-to-outflow centroid lag time for a one year, 24 hour design storm. We used pressure transducers to measure pond water surface elevation at 5 min intervals, and calculated pond outflow and volume using rating curves obtained from site stormwater management plans (SWMPs). Peak inflows, peak outflows, and runoff ratios frequently exceeded SWMP calculations in measured events. Four ponds never achieved the required 24 hour inflow-to-outflow centroid lag for storms similar to the one year, 24 hour storm. These BMPs fail to achieve regulatory goals for channel protection because of regulatory loopholes, underprediction of rainfall intensity, unrealistic predictions of postdevelopment flows in SWMPs, and the inability of wet retention ponds to reduce overall runoff volume. While specific to one locality, the shortcomings highlighted suggest similar field-based assessments of retention pond performance are needed in other locations.  相似文献   

5.
Numerous road and railway construction projects include costly mitigation measures to offset the barrier effect produced on local fauna, despite the scarcity of data on the effectiveness of such mitigation measures. In this study, we evaluate the utility of different types of crossing structures. Vertebrate use of 43 transverse crossing structures along the A-52 motorway (north-western Spain) was studied during spring 2001. Research centered on wildlife passages (9), wildlife-adapted box culverts (7), functional passages (6 overpasses, 7 underpasses) and culverts (14), with marble dust being used to record animal tracks. A total of 424 track-days were recorded, with most of the larger vertebrate groups present in the area being detected. All crossing structure types were used by animals, although the intensity of use varied significantly among them (Kruskal-Wallis test, p<0.05); culverts were used less frequently than other structures. Crossing structure type and width were identified as the most important factors in their selection for use. Wildlife passages and adapted culverts allowed crossing by certain species (wild boar, roe deer, Eurasian badger), which do not tend to cross elsewhere. These results highlight the importance of using both mixed-type structures and wildlife passages in reducing the barrier effect of roads.  相似文献   

6.
In the relatively pristine ecosystem in Kejimkujik Park, Nova Scotia, methylmercury (MeHg) concentrations in loons, Gavia immer, are among the highest recorded anywhere in the world. This study investigated the influence of bedrock lithology on MeHg concentrations in wetlands. Twenty-five different wetland field sites were sampled over four different bedrock lithologies; Kejimkujik monzogranite, black sulfidic slate, gray slate, and greywacke. Soil samples were analyzed for ethylmercury (EtHg), MeHg, total Hg, acid-volatile sulfides (AVS), organic matter, and water content as well as the biological parameters, mercury methyltransferase (HgMT) activity, sulfate reduction rates, fatty acid methyl ester (FAME) composition, and acidity. Methylmercury concentrations in the wetlands were highly dependent (P < 0.08) on lithology with no significant difference between bogs, fens, and swamps. Methylmercury concentrations in wetland soils developed on Kejimkujik monzogranite averaged 900 ng kg(-1) compared with only 300 ng kg(-1) in wetland soils developed on black sulfidic slate. Fatty acid methyl ester composition was also lithologically dependent (P < 0.001) with biomarkers for Desulfobulbus spp. discriminating between sites containing high and low MeHg concentrations. Levels of MeHg in wetlands were predicted mainly (41% of the sum of squares) by HgMT activity that differed (P < 0.009) between wetlands, with activity in bogs almost three times that present in swamps. Wetland MeHg concentrations are highly dependent on the lithology on which they have developed for largely biological reasons.  相似文献   

7.
Rocky intertidal habitats frequently are used by humans for recreational, educational, and subsistence-harvesting purposes, with intertidal populations damaged by visitation activities such as extraction, trampling, and handling. California Marine Managed Areas, particularly regulatory marine reserves (MRs), were established to provide legal protection and enhancement of coastal resources and include prohibitions on harvesting intertidal populations. However, the effectiveness of MRs is unclear as enforcement of no-take laws is weak and no regulations protect intertidal species from other detrimental visitor impacts such as trampling. The goal of this study was two-fold: (1) to determine impacts from human visitation on California mussel populations (Mytilus californianus) and mussel bed community diversity; and (2) to investigate the effectiveness of regulatory MRs in reducing visitor impacts on these populations. Surveys of mussel populations and bed-associated diversity were compared: (1) at sites subjected to either high or low levels of human use, and (2) at sites either unprotected or with regulatory protection banning collecting. At sites subjected to higher levels of human visitation, mussel populations were significantly lower than low-use sites. Comparisons of mussel populations inside and outside of regulatory MRs revealed no consistent pattern suggesting that California no-take regulatory reserves may have limited effectiveness in protecting mussel communities. In areas where many people visit intertidal habitats for purposes other than collecting, many organisms will be affected by trampling, turning of rocks, and handling. In these cases, effective protection of rocky intertidal communities requires an approach that goes beyond the singular focus on collecting to reduce the full suite of impacts.  相似文献   

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