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81.
82.
Management strategies to reduce the risks to human life and property from wildfire commonly involve burning native vegetation. However, planned burning can conflict with other societal objectives such as human health and biodiversity conservation. These conflicts are likely to intensify as fire regimes change under future climates and as growing human populations encroach farther into fire‐prone ecosystems. Decisions about managing fire risks are therefore complex and warrant more sophisticated approaches than are typically used. We applied a multicriteria decision making approach (MCDA) with the potential to improve fire management outcomes to the case of a highly populated, biodiverse, and flammable wildland–urban interface. We considered the effects of 22 planned burning options on 8 objectives: house protection, maximizing water quality, minimizing carbon emissions and impacts on human health, and minimizing declines of 5 distinct species types. The MCDA identified a small number of management options (burning forest adjacent to houses) that performed well for most objectives, but not for one species type (arboreal mammal) or for water quality. Although MCDA made the conflict between objectives explicit, resolution of the problem depended on the weighting assigned to each objective. Additive weighting of criteria traded off the arboreal mammal and water quality objectives for other objectives. Multiplicative weighting identified scenarios that avoided poor outcomes for any objective, which is important for avoiding potentially irreversible biodiversity losses. To distinguish reliably among management options, future work should focus on reducing uncertainty in outcomes across a range of objectives. Considering management actions that have more predictable outcomes than landscape fuel management will be important. We found that, where data were adequate, an MCDA can support decision making in the complex and often conflicted area of fire management.  相似文献   
83.
Price JN  Hiiesalu I  Gerhold P  Pärtel M 《Ecology》2012,93(6):1290-1296
The existence of deterministic assembly rules for plant communities remains an important and unresolved topic in ecology. Most studies examining community assembly have sampled aboveground species diversity and composition. However, plants also coexist belowground, and many coexistence theories invoke belowground competition as an explanation for aboveground patterns. We used next-generation sequencing that enables the identification of roots and rhizomes from mixed-species samples to measure coexisting species at small scales in temperate grasslands. We used comparable data from above (conventional methods) and below (molecular techniques) the soil surface (0.1 x 0.1 x 0.1 m volume). To detect evidence for nonrandom patterns in the direction of biotic or abiotic assembly processes, we used three assembly rules tests (richness variance, guild proportionality, and species co-occurrence indices) as well as pairwise association tests. We found support for biotic assembly rules aboveground, with lower variance in species richness than expected and more negative species associations. Belowground plant communities were structured more by abiotic processes, with greater variability in richness and guild proportionality than expected. Belowground assembly is largely driven by abiotic processes, with little evidence for competition-driven assembly, and this has implications for plant coexistence theories that are based on competition for soil resources.  相似文献   
84.
Rats excreted the 14C from a single oral dose of N-isopropyl-N-[14C]phenyloxamic acid [I, a soil metabolite from 2-chloro-N-isopropylacetanilide (propachlor)] in approximately equal quantities in the urine (49.2%) and feces (48.2%). A milking goat given daily oral doses of [14C]-I (1 mg of I three times daily) excreted more 14C in the feces (56.6%) than it excreted in the urine. From both species, I accounted for 97 to 100% of the urinary 14C, and all of the 14C that was extractable from the feces (73 to 75% of the 14C in feces was extractable with methanol). Goat milk samples collected 16 hr after the last dose contained no detectable 14C. Tissue residues of 14C were determined.  相似文献   
85.
86.
Fifteen metabolites of crufomate (4-tert-butyl-2-chlorophenyl methyl methylphosphoramidate, I) were identified in the excreta from rats given single oral doses of I. Compound I was not detected in either the urine or the feces. The metabolic reactions observed were N-and O-demethylation, oxidations of the t-butyl moiety, replacement of the H-N-CH3 with an OH moiety, hydrolysis of the phosphoramidate moiety to yield the phenol, conjugation with glucuronic acid, and combinations of these reactions. No ring dehalogenation or ring substitution was observed.  相似文献   
87.
Summary Exploitation of energy resources need not imply irreperable damage to our physical environment. Unfortunately lack of involvement at the policy planning stage hinders significant improvements despite the enthusiastic but fragmented endeavours of interested parties.Evaluation of alternative strategies must keep pace with prospecting and engineering to achieve real influence upon the ultimate location, scale and form of development.Fruitful examination of policy alternatives is hindered by the competition between energy industries in the UK perpetuated by the apparent lack of a national energy strategy.The fast increasing bulk of environmental guidelines and proposed European legislation will not of itself prevent the significant environmental impact of energy exploitation.There is as yet no legislation in the United Kingdom requiring a developer to submit an environmental impact assessment with a planning application. However, many recent project proposals have been accompanied by such, either voluntarily or at the request of the local planning authority. The quality of such submissions ranges from the superficial to substantial, but few demonstrate evidence of environmental influence on policy formulation, alternative site selection or development characteristics.Recent experience in the UK has achieved significant success in the early introduction of physical planning and environmental criteria during the exploration of Western Europe's largest recoverable deep coal reserves.Environmental influence was achieved through close collaboration between client and consultants. Early discussion with local authorities and other agencies established during coal field exploration provided the basis for ongoing consultation during the four-year study period. Publication of consultants' findings and submission of planning proposals culminated in a public inquiry providing opportunity for public involvement over 84 days of project examination.David Price is an Architect and Town Planner in private practice with extensive experience in urban and regional planning and environmental evaluation in the UK and abroad. He is also a member of Land Planning Group, a multi-disciplined design and planning consultancy.  相似文献   
88.
Putting cash values on the environment facilitates commoditization and political capture of evaluation. However, individual citizens may also wish to know the appropriate trade‐off of values, in order to use political power properly. Willingness‐to‐pay offers insight into consumers’ valuation of landscape, but routine application of economic methods to land use decisions meets major problems, especially the data needs of cost — benefit analysis in face of the urgency of decisions, and the insensitivity of conventional methods to subtle landscape changes. These problems require the citizen‐as‐consumer to make personal judgements of value, but to link those values to a cash scale for the purpose of making trade‐offs. Such judgements can be entered into an orderly framework, in which the judgements can be exposed for comment, which itself exposes the assumptions of commentators. The decision about routing electricity transmission lines in Scotland provides an example. Recent interest in environmental economics gives the opportunity to broaden the scope of the method.  相似文献   
89.
Correlational studies have identified worksite coping resources such as social support and perceived control, and have suggested a positive role for such resources in employee stress processes. However, little experimental evidence has demonstrated the causal role of worksite coping resources in improving mental health, nor how worksite coping resources can be enhanced. This paper reports the results of a field experiment intended to provide such evidence. Human service workers participated in a theory-driven training program designed to increase individual and group psychosocial coping resources and individuals' abilities to use those resources when coping with job demands. The inclusion of selection variables in models used to estimate the impact of the intervention controlled for selection biases and also allowed for the assessment of the impact of the training on those workers identified as most prone to turnover and on those most likely to participate in such an intervention. Results indicated that the program enhanced the work team climate and reduced depresssive symptoms and somatization in those most at risk for leaving their jobs. The program was also effective in increasing the amount of supervisor support received on the job and strengthening perceptions of coping abilities in those workers most likely to participate in the program.  相似文献   
90.
A new organic N-chloramine disinfectant (3-chloro-4, 4-dimethyl-2-oxazolidinone, agent I) has been compared with calcium hypochlorite as to its tendency to react with organic matter in water to produce toxic trihalomethanes. Agent I reacts much less readily with organic demand than does calcium hypochlorite. This study shows that agent I should be safe to use as a disinfectant for water containing appreciable organic load in either sunlight or darkness. On the other hand, calcium hypochlorite may not be a satisfactory disinfectant from the toxicity standpoint for water which contains organic load which must be stored for extended time periods in either sunlight or darkness.  相似文献   
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