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91.
This article presents a model for local energy planning and its application in a full-scale experiment in a Swedish municipality. The model is based on legal requirement, research findings and standards of good practice and includes a combination of analytical and procedural tools intended to support rational decision-making: external scenarios, a citizens’ panel, life cycle analysis and qualitative environmental assessment (EA). The application of the model indicates that the decision-support tools selected can give several new and valuable inputs to local energy planning, such as local knowledge and values through citizen dialogue and comprehensive EAs. However, the experiment also shows that there are several challenges involved in applying the tools, for example, it is difficult to get citizens and the industry to participate and that it is complicated to combine several different tools for decision-making into a single planning process. Moreover, the experiences from the application suggest that the model for local energy planning show great potential but needs to be improved before it can be used as a standard of good practice.  相似文献   
92.

Agrochemicals including neonicotinoid insecticides and fungicides are frequently applied as seed treatments on corn, soybeans, and other common row crops. Crops grown from pesticide-treated seed are often directly planted in managed floodplain wetlands and used as a soil disturbance or food resource for wildlife. We quantified invertebrate communities within mid-latitude floodplain wetlands and assessed their response to use of pesticide-treated seeds within the floodplain. We collected and tested aqueous and sediment samples for pesticides in addition to sampling aquatic invertebrates from 22 paired wetlands. Samples were collected twice in 2016 (spring [pre-water level drawdown] and autumn [post-water level flood-up]) followed by a third sampling period (spring 2017). Meanwhile, during the summer of 2016, a portion of study wetlands were planted with either pesticide-treated or untreated corn seed. Neonicotinoid toxic equivalencies (NI-EQs) for sediment (X??=?0.58 μg/kg), water (X??=?0.02 μg/L), and sediment fungicide concentrations (X??=?0.10 μg/kg) were used to assess potential effects on wetland invertebrates. An overall decrease in aquatic insect richness and abundance was associated with greater NI-EQs in wetland water and sediments, as well as with sediment fungicide concentration. Post-treatment, treated wetlands displayed a decrease in insect taxa-richness and abundance before recovering by the spring of 2017. Information on timing and magnitude of aquatic insect declines will be useful when considering the use of seed treatments for wildlife management. More broadly, this study brings attention to how agriculture is used in wetland management and conservation planning.

  相似文献   
93.
The comparative in vitro metabolism of the flame retardant tetrabromo-bisphenol A was studied in rat and human using a [(14)C]-radio-labelled molecule. Tetrabromo-bisphenol A is metabolised into the corresponding glucuronide (liver S9 fractions) and several other metabolites produced by cytochrome P450 dependent pathways (liver microsomes and liver S9 fractions). No major qualitative differences were observed between rat and human, regardless of the selected concentration, within the 20-200 microM range. Tetrabromo-bisphenol A undergoes an oxidative cleavage near the central carbon of the molecule, that leads to the production of hydroxylated dibromo-phenol, hydroxylated dibromo-isopropyl-phenol and glutathione conjugated dibromo-isopropyl-phenol. The main metabolites of tetrabromo-bisphenol A are two molecules of lower polarity than the parent compound, characterised as a hexa-brominated compound with three aromatic rings and a hepta-brominated dimer-like compound, respectively. Both structures, as well as the lower molecular weight metabolites resulting from the breakdown of the molecule, suggest the occurrence of chemically reactive intermediates formed following a first step oxidation of tetrabromo-bisphenol A.  相似文献   
94.
95.
Many sites of former ammunition plants are contaminated with the explosive 2,4,6-trinitrotoluene, its derivatives and reduction products. Such nitroaromatic compounds have a high human and ecotoxic potential. Plant uptake of these organic pollutants is known and could be confirmed under field conditions. In this paper rhizospheric soil was analyzed to characterize the effect of vegetation on TNT-contaminated soil. Common beans (Phaseolus vulgaris) were used as test plants. The experiments were performed on two areas with different TNT concentrations. The data reveal a significant decrease of extractable TNT in rhizospheric soil by a factor of 5 to 6 during the vegetation period. On the area with high TNT concentration, an enrichment of nitroaromatic compounds in root tissue was found compared to the rhizospheric soil. Aminodinitrotoluene could be confirmed as the primary pollutant in the root. These results refer to a potential application of plants to biological remediation of soil contaminated with ammunition-specific pollutants.  相似文献   
96.
97.
We studied variability in foraging behavior of Noctilio albiventris (Chiroptera: Noctilionidae) in Costa Rica and Panamá and related it to properties of its echolocation behavior. N. albiventris searches for prey in high (>20 cm) or low (<20 cm) search flight, mostly over water. It captures insects in mid-air (aerial captures) and from the water surface (pointed dip). We once observed an individual dragging its feet through the water (directed random rake). In search flight, N. albiventris emits groups of echolocation signals (duration 10–11 ms) containing mixed signals with constant-frequency (CF) and frequency-modulated (FM) components, or pure CF signals. Sometimes, mostly over land, it produces long FM signals (duration 15–21 ms). When N. albiventris approaches prey in a pointed dip or in aerial captures, pulse duration and pulse interval are reduced, the CF component is eliminated, and a terminal phase with short FM signals (duration 2 ms) at high repetition rates (150–170 Hz) is emitted. Except for the last pulses in the terminal phase N. albiventris avoids overlap between emitted signals and echoes returning from prey. During rakes, echolocation behavior is similar to that in high search flight. We compare N. albiventris with its larger congener, N. leporinus, and discuss behavioral and morphological specializations that can be interpreted as preadaptations favoring the evolution of piscivory as seen in N. leporinus. Prominent among these specializations are the CF components of the echolocation signals which allow detection and evaluation of fluttering prey amidst clutter-echoes, high variability in foraging strategy and the associated echolocation behavior, as well as morphological specializations such as enlarged feet for capturing prey from the water surface. Received: 21 April 1997 / Accepted after revision: 12 January 1998  相似文献   
98.
99.
We used both field and flight cage observations to investigate the echolocation and foraging behavior of the seldom studied, small, aerial insectivorous bat Myotis nigricans (Vespertilionidae) in Panama. In contrast to its temperate congeners, M. nigricans foraged extensively in open space and showed an echolocation behavior well adapted to this foraging habitat. It broadcast narrowband echolocation signals of 7 ms duration that enhance the chance of prey detection in open space. Because of rhythmical alternations of signal amplitude from signal to signal in our sound recordings of search signals in open space, we conclude that the bats scanned their environment with head movements, thereby enlarging their search volume. In edge-and-gap situations, and in the flight cage, M. nigricans introduced an initial broadband component to its search calls. In the field and in the flight cage, M. nigricans hawked for prey in aerial catches; gleaning was never observed. M. nigricans demonstrates call structures, such as narrow bandwidth and rather long signals adapted to foraging predominantly in open space. Moreover, call structure is highly plastic, allowing M. nigricans to forage in edge-and-gap situations also. These adaptations in call structure and plasticity have evolved convergently at least twice within the genus Myotis. Finally, M. nigricans echolocation and foraging behavior parallels that of the small, aerial, insectivorous pipistrelle bats (Vespertilionidae), which are not closely related to M. nigricans but forage in similar habitats.  相似文献   
100.
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