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An international concern with climate change has prompted a political commitment to the use of renewable energies. Yet, the operationalization and management of this political objective may be frustrated at the local level, where, it is suggested, an implementation impasse exists. This paper reports on a case study that examines the planning issues around the harvesting of wind at an urban brownfield site in Scotland. The paper discusses the nature of the state-market-civil relations involved in the development management of private wind-energy infrastructure, and the potential for a positive mediating role for the planning system. 相似文献
23.
Cicada emergence in Southwestern riparian forest: influences of wildfire and vegetation composition.
Annually emerging cicadas are a numerically and ecologically dominant species in Southwestern riparian forests. Humans have altered disturbance regimes that structure these forests such that floods are less common and wildfires occur more frequently than was historically the case. Impacts of these changes on primary consumers such as riparian cicadas are unknown. Because cicadas are consumed by a variety of animal species, disturbances that alter timing of their emergence or abundance could have consequences for species at higher trophic levels. We trapped emerging cicadas (Tibicen dealbatus) in burned and unburned riparian forest plots along the Middle Rio Grande in central New Mexico (USA) to determine effects of wildfire and vegetation structure on their density and phenology. We measured vegetation variables and soil temperature at cicada traps and related these variables to variation in emergence density and phenology. We also experimentally heated soil under emergence traps to examine the relationship between soil temperature and emergence phenology. Emergence density was similar in wildfire and unburned plots, though emergence date averaged earlier in wildfire plots and experimentally heated traps. We identified models containing cottonwood proximity (distance from the nearest cottonwood tree) and cottonwood canopy coverage as the most parsimonious explanations of emergence density at each trap. Model selection results were consistent with the literature and field observations that showed that cottonwood trees are an essential resource for T. dealbatus. Cottonwood canopy was also correlated with low soil temperatures, which are associated with later emergence dates. Failure of cottonwoods to reestablish following wildfire could result in cicadas emerging at lower densities and at earlier dates. For cicadas to emerge at densities and times that provide the greatest benefits to birds and other riparian-obligate secondary consumers, riparian forests should be protected from fire, and native vegetation in wildfire sites should be restored. 相似文献
24.
Norman Kaplan Eric Soderberg Deborah Pickett James Meyers 《Journal of the Air & Waste Management Association (1995)》2013,63(6):773-780
The IAPCS model, developed by U.S. EPA’s Air and Energy Engineering Research Laboratory and made available to the public through the National Technical Information Service, can be used by utility companies, architectural and engineering companies, and regulatory agencies at all levels of government to evaluate commercially available technologies for control of SO2, NOx, and particulate matter emissions from coal-fired utility boilers with respect to performance and cost. The model is considered to be a useful tool to compare alternative control strategies to be used by utilities to comply with the requirements of the CAA, and to evaluate the sensitivity of control costs with respect to many of the significant variables affecting costs. To illustrate the use of the model for site-specific studies, the authors used the model to estimate control costs for SO2 and NOx control at Detroit Edison’s Monroe plant and two hypothetical plants under consideration and at three plants operated by New York State Electric and Gas Corporation. The economic and technical assumptions used to drive the model were those proposed by the utilities if cited, and if not cited, the model default values were used. The economic format and methodologies for costs cited in the Electric Power Research Institute’s Technical Assessment Guide are used in the IAPCS model. Depending on the specific conditions and assumptions for the cases evaluated, SO2 control costs ranged from $417 to $3,159 per ton of SO2 removed, and NOx control costs ranged from $461 to $3,537 per ton of NOx removed or reduced. 相似文献
25.
Martha E. Rode Michael T. Mennuti Rose M. Giardine Elaine H. Zackai Deborah A. Driscoll 《黑龙江环境通报》2001,21(7):575-580
We report the mid-trimester prenatal diagnosis of Neu–Laxova syndrome (NLS) in two at risk families utilizing serial sonographic examinations. Ultrasound and pathologic findings from seven affected pregnancies, the largest case series of NLS to date, are presented. One fetus had anencephaly and incomplete rachischisis, an anomaly that has not been previously reported in association with NLS. Ultrasonographic detection of severe intrauterine growth restriction (IUGR), abnormally postured limbs, microcephaly, and edema allowed prenatal diagnosis of NLS in five of these at risk pregnancies during the mid-trimester. Growth curves derived from serial sonograms reveal abnormalities of all standard biometric measurements. The growth discrepancy was most pronounced in the measurements of the biparietal diameter, which were consistently less than two standard deviations below the mean across all gestational ages. This case series confirms that aberrant growth and anomalies may be detected sufficiently early in gestation to permit prenatal diagnosis of NLS. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Karin S. Holland Raymond E. Lewis Karina Tipton Stella Karnis Carol Dona Erik Petrovskis Louis P. Bull Deborah Taege Christopher Hook 《补救:环境净化治理成本、技术与工艺杂志》2011,21(3):7-38
The US Sustainable Remediation Forum (SURF) created this Framework to enable sustainability parameters to be integrated and balanced throughout the remediation project life cycle, while ensuring long‐term protection of human health and the environment and achieving public and regulatory acceptance. Parameters are considerations, impacts, or stressors of environmental, social, and economic importance. Because remediation project phases are not stand‐alone entities but interconnected components of the wider remediation system, the Framework provides a systematic, process‐based approach in which sustainability is integrated holistically and iteratively within the wider remediation system. By focusing stakeholders on the preferred end use or future use of a site at the beginning of a remediation project, the Framework helps stakeholders form a disciplined planning strategy. Specifically, the Framework is designed to help remediation practitioners (1) perform a tiered sustainability evaluation, (2) update the conceptual site model based on the results of the sustainability evaluation, (3) identify and implement sustainability impact measures, and (4) balance sustainability and other considerations during the remediation decision‐making process. The result is a process that encourages communication among different stakeholders and allows remediation practitioners to achieve regulatory goals and maximize the integration of sustainability parameters during the remediation process. © 2011 Wiley Periodicals, Inc. 相似文献
28.
Deborah R. R. Smith 《Behavioral ecology and sociobiology》1983,13(2):107-114
Summary
Philoponella oweni (Uloboridae) is a facultatively communal spider found in the southwestern United States. Solitary females and communal groups of females coexist in the same habitats. Communal females are known to produce more eggs than solitary females. Communal females might acquire the energy for the production of additional eggs by one of three means: they might have a longer life span, and thus more time in which to acquire energy; web maintenance might be more efficient in a communal group; or communal females might spend more time feeding. Field data from a marked population in Arizona showed the third alternative was true.Two possible causes for the greater time spent feeding by communal females were investigated; either the communal web or group is a more efficient trap for insects, or the communal groups are located at sites where insects are more abundant. Analysis of feeding rates and sticky trap data confirmed the second alternative.Potential web attachment sites are limited in some habitats, and mortality during dispersal is very high. When potential web attachment sites are scarce more of the population is found in communal groups; when they are abundant more of the population is solitary. The pattern of dispersal and overwintering is this species suggests that females renewing a colony in the spring could be related. 相似文献
29.
Joel W. McGlothlin Deborah L. Duffy Jessica L. Henry-Freeman Ellen D. Ketterson 《Behavioral ecology and sociobiology》2007,61(9):1391-1399
Sexually selected traits that act as signals of quality often display some degree of condition dependence. In birds, condition
dependence of ornamental plumage is often mediated by production costs related to acquisition or allocation of dietary resources.
White plumage ornaments, however, have often been assumed to be inexpensive because their production requires neither pigment
nor specialized feather structure. In male dark-eyed juncos (Junco hyemalis), the size of a white patch on the tail contributes to attractiveness and mating success. Using captive males, we examined
the effects of diet quality on the size and brightness of the tail-white patch. After removing four tail feathers to induce
replacement, we maintained subjects on a subsistence (low-protein) or enriched (high-protein) diet while induced feathers
grew. Birds that received an enriched diet grew their feathers more quickly and grew larger, brighter white patches. Feather
growth rate was positively correlated with the increase in the size of the tail-white patch, a relationship that was stronger
in the subsistence diet group. However, within diet treatments, faster-grown feathers were slightly duller. Taken together,
these results suggest that variation in diet quality may lead to condition-dependent expression of tail white and that condition
dependence may be stronger in more stressful environments. We suggest a mechanism by which increased feather growth rate may
lead to an increase in the size of the tail-white patch and discuss potential trade-offs between signal size and brightness. 相似文献
30.
We used strontium isotopes and analysis of foliar and soil nutrients to test whether erosion can rejuvenate the supply of rock-derived nutrients in the lowland tropical rain forest of La Selva, Costa Rica. We expected that these nutrients would be depleted from soils on stable surfaces, a result of over one million years of weathering in situ. In fact, trees and palms in all landscape positions derive a relatively high percentage (> or =40%) of their strontium from bedrock, rather than atmospheric, sources. The fraction that is rock-derived increases on slopes, but with no detectable effect on plant macronutrient concentrations. These results differ from those in a similar ecosystem on Kauai, Hawaii, where plants on uneroded surfaces derive almost all of their foliar Sr from atmospheric, rather than bedrock, sources. The results from La Selva challenge the assumption that tropical Oxisols in general have low nutrient inputs from bedrock, and support the hypothesis that erosion can increase the supply of these nutrients in lower landscape positions. 相似文献