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61.
The utilisation of Social Impact Assessment (SIA) in Iran is analysed in terms of its policy context and its application in practice. Five case studies where SIA was employed in conjunction with Environmental Impact Assessments (EIA) for agricultural development projects are evaluated. In addition, the performance of the policy context is assessed. This research revealed that there are legal and institutional constraints to the effective functioning of SIA in Iran, and that there are deficiencies in the operating guidelines. There were serious problems associated with the way SIA was undertaken in all five case studies. Recommendations to improve the policy framework for the conduct of SIA are made. The recommendations advocate for a higher profile of SIA within legislation, for social issues to have greater emphasis in official guidelines for the conduct of EIA and SIA, and for a range of measures to increase the professionalism of SIA practice.  相似文献   
62.
For more than two decades a number of frameworks for scientific knowledge production are being proposed by science and technology researchers. They all advocate an extended involvement of non-specialists, in particular when it comes to knowledge production applicable to practical societal problems. We look to what extent these new frameworks have taken ground within a particular research community: the ACCENT Network of Excellence which coordinates European atmospheric chemistry and physics research applicable to air pollution and climate change. We did so by stimulating a debate through a “blog”, a survey and in-depth interviews with ACCENT scientists about the interaction between science, policy making and civil society, to which a great deal of ACCENT member contributed in writing or verbally. Most of them had interactions with policy makers and/or the general public, and they generally believe that interactions with spheres other than the scientific are needed. While such interactions give personal insight and satisfaction, they seem to have little impact on the goals and the practice of the scientific work itself. Extended frameworks of science production that go beyond the disciplinary mode seem to emerge at the level of individual scientists, yet they still need to find their way to the level of scientific project management. In this paper we discuss the justifications and barriers to implement a higher degree of extended knowledge integration in applied science projects such as ACCENT. It is felt that the community of atmospheric chemists and physicists is mature for such an implementation and recommendations are given to help and make this happen.  相似文献   
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The extent to which genetic divergence can occur in the absence of physical barriers to gene flow is currently one of the most controversial topics in evolutionary biology, with implications for our understanding of speciation, phenotypic plasticity and adaptive potential. This is illustrated by a recent study reporting a surprising pattern of genetic differentiation between intertidal and subtidal morphotypes of the broadcast-spawning Antarctic limpet Nacella concinna. To explore this further, we collected almost 400 Antarctic limpets from four depths (intertidal, 6, 15 and 25 m) at Adelaide island, Antarctica, and conducted a combined morphometric and genetic analysis using 168 polymorphic amplified fragment length polymorphism (AFLP) loci. Morphological analysis revealed not only pronounced differences between the two morphotypes, but also a continuous cline in shell shape from the intertidal zone down to 25 m depth, suggesting that the distinction between the morphotypes may be artificial. Moreover, genetic analysis using both F st and a Bayesian analogue found no evidence for differentiation either between the two morphotypes or by depth, and a Bayesian cluster analysis did not detect any cryptic genetic structure. Our findings lend support to the notion that limpets can be phenotypically highly plastic, although further studies are required to determine unequivocally whether there is any genetic basis to the observed variation in shell morphology.  相似文献   
65.
A modeler must often rely on highly simplified representations of complex physical systems when analyzing associated economic issues. Herein, we consider a management problem in which a bioeconomic system exhibits simultaneity in processes governing productivity and damage. In this case, it may benefit the producer to sacrifice productivity to reduce the costs associated with increased damage. We specify empirically a structural damage relationship that explains the biological process by which an invasive species damages a host and estimate the structural model and its reduced form with an exceptional dataset on infestation of olives by the olive fruit fly. We contrast the results of these models with the approach typically taken in the economic literature, which expresses damage as a function of pest density. The population-based approach introduces significantly greater bias into the individual grower's choice of damage-control inputs than estimates based on the structural model.  相似文献   
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Abstract

The effects of the herbicide triclopyr (3,5,6‐trichloro‐2‐pyridinyloxyacetic acid) on the mineralization of 2,4‐D (2,4‐dichlorophenoyxacetic acid) in two soils which differed in their histories of prior exposure to the two herbicides were investigated. The relative effects of triclopyr on 2,4‐D mineralization and most probable numbers of 2,4‐D degraders were dependent upon the soil. Triclopyr was shown to increase 2,4‐D mineralization rates in a soil which had been exposed to both 2,4‐D and triclopyr, but decreased the mineralization rate of 2,4‐D and inhibited the increase of most probable numbers of 2,4‐D degraders in a soil that had not been directly exposed to either herbicide.  相似文献   
68.
Macroinvertebrates were examined on an impounded valley marsh in Stonington, Connecticut, that has changed from aTypha-dominated system to one with typical salt-marsh vegetation during 13 years following the reintroduction of tidal exchange. Animal populations on this restored impounded marsh were evaluated by comparing them with populations on a nearby unimpounded valley marsh of roughly the same size. Populations of the high marsh snail,Melampus bidentatus Say, were quantitatively sampled along transects that extended from the water-marsh edge to the upland; those of the ribbed mussel,Geukensia demissa Dillwyn, were sampled in low marsh areas on transects along the banks of creeks and mosquito ditches. The occurrence of other marsh invertebrates also was documented, but their abundance was not measured. The mean density ofMelampus was 332±39.6 SE/m2 on the restored impounded marsh and 712±56.0 SE/m2 on the unimpounded marsh. However, since snails were larger on the restored impounded marsh, the difference in snail biomass was less pronounced than the difference in snail density. MeanMelampus biomass was 4.96±0.52 SE g dry wt/m2 on the restored impounded marsh and 6.96±0.52 SE g dry wt/m2 on the unimpounded marsh. On the two marshes, snail density and biomass varied in relation to plant cover and other factors. The density and biomass ofGeukensia at the edge of the marsh were comparable on the restored impounded and unimpounded marshes. Mean mussel densities ranged from 80 to 240/m2 and mean mussel biomass varied from 24.8–64.8 g dry wt/m2 in different low marsh areas. In contrast, below the impoundment dike, meanGeukensia density was 1100±96.4 SE/m2 and meanGeukensia biomass was 303.6±33.28 SE g dry wt/m2. A consideration of all available evidence leads to the conclusion that the impounded marsh is in an advanced phase of restoration.  相似文献   
69.
The purpose of this study was to estimate the total medical care costs of individuals injured in motor vehicle crashes and in crashes where alcohol was involved. Crashes were studied that involved 2,728 vehicle occupants and 191 pedestrians with injuries as reported in 1979 by the National Accident Sampling System, a probability sample of all motor vehicle crashes occurring in the united States. Medical care costs were assigned by using Abbreviated Injury Scale codes in accordance with other published research. Determination of alcohol involvement was based on crash characteristics. Results indicate that 20.2 % of medical care costs for motor vehicle crash injuries may be due to crashes where alcohol was involved. It was estimated that alcohol-related motor vehicle crashes cost between $434 million and $483 million in medical care alone in the United States in 1979.  相似文献   
70.
Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.  相似文献   
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