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121.
Perspectives on the Use of Green Infrastructure for Stormwater Management in Cleveland and Milwaukee 总被引:1,自引:0,他引:1
Melissa Keeley Althea Koburger David P. Dolowitz Dale Medearis Darla Nickel William Shuster 《Environmental management》2013,51(6):1093-1108
Green infrastructure is a general term referring to the management of landscapes in ways that generate human and ecosystem benefits. Many municipalities have begun to utilize green infrastructure in efforts to meet stormwater management goals. This study examines challenges to integrating gray and green infrastructure for stormwater management, informed by interviews with practitioners in Cleveland, OH and Milwaukee WI. Green infrastructure in these cities is utilized under conditions of extreme fiscal austerity and its use presents opportunities to connect stormwater management with urban revitalization and economic recovery while planning for the effects of negative- or zero-population growth. In this context, specific challenges in capturing the multiple benefits of green infrastructure exist because the projects required to meet federally mandated stormwater management targets and the needs of urban redevelopment frequently differ in scale and location. 相似文献
122.
Andrea Gori Sergio Rossi Elisa Berganzo Joan Lluis Pretus Mark R. T. Dale Josep-Maria Gili 《Marine Biology》2011,158(1):143-158
Most of the current knowledge on Mediterranean gorgonians is restricted to investigations of those populations found within
shallow sublittoral waters, and only limited data are available for populations located below scuba depth. To overcome this
lack of information, the occurrence and abundance of the gorgonians Eunicella singularis, Paramuricea clavata, and Leptogorgia sarmentosa were investigated in northwestern Mediterranean benthic communities over a wide geographical (60 km of coastline) and bathymetrical
(0–70 m deep) extent using a remotely operated vehicle (ROV). The greatest occurrence and abundances of E. singularis and P. clavata were concentrated in areas that are directly exposed to strong near-bottom currents. E. singularis was the most common and abundant species and displayed great plasticity and amplitude in its environmental preferences. Conversely,
P. clavata showed a very patchy distribution that was associated with vertical rocky walls. Only isolated colonies of L. sarmentosa were observed in the study area. Hot spots of abundance of E. singularis and P. clavata were identified below a depth of 40 m, which demonstrates the importance of studying the distribution of benthic species
over a wide geographical and bathymetrical extent. 相似文献
123.
The honesty of ornamental signals of quality is often argued to be enforced via costs associated with testosterone. It is
still poorly understood, however, how seasonal variation of testosterone within individuals is related to the timing and extent
of ornament development. Here, we studied inter- and intra-individual variability of plasma testosterone levels in a population
of 150 captive male house sparrows (Passer domesticus) through the course of a full year. We further analyzed the relationship between plasma testosterone levels and two sexually
dimorphic ornaments: badge size and bill coloration. Also, because of a known negative relation between molt and circulating
testosterone levels, we analyzed the relationship between ornamentation and molt status during the fall. We found that testosterone
levels increased towards the breeding season and decreased before the onset of annual molt. However, within individuals, relative
testosterone titers demonstrated low repeatability between seasons. Plasma testosterone levels were not correlated with badge
size in any season but were correlated strongly with bill coloration during all periods, except the breeding season when variation
in bill color was low. Finally, we found that bill coloration strongly correlated with molt status during fall. Our results
indicate that bill coloration, not badge size, is the best ornamental indicator of a “running average” of male testosterone
in house sparrows and therefore the best potential indicator of qualities and/or behavioral strategies associated with testosterone. 相似文献
124.
Cameron “Dale” Bass Martin Davis Mark “Steve” Rountree Robert M. Harris Ellory Sanderson 《International journal of occupational safety and ergonomics》2013,19(4):347-361
To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax.A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn. 相似文献
125.
Rebecca A. Efroymson Virginia H. Dale Keith L. Kline Allen C. McBride Jeffrey M. Bielicki Raymond L. Smith Esther S. Parish Peter E. Schweizer Denice M. Shaw 《Environmental management》2013,51(2):291-306
Indicators of the environmental sustainability of biofuel production, distribution, and use should be selected, measured, and interpreted with respect to the context in which they are used. The context of a sustainability assessment includes the purpose, the particular biofuel production and distribution system, policy conditions, stakeholder values, location, temporal influences, spatial scale, baselines, and reference scenarios. We recommend that biofuel sustainability questions be formulated with respect to the context, that appropriate indicators of environmental sustainability be developed or selected from more generic suites, and that decision makers consider context in ascribing meaning to indicators. In addition, considerations such as technical objectives, varying values and perspectives of stakeholder groups, indicator cost, and availability and reliability of data need to be understood and considered. Sustainability indicators for biofuels are most useful if adequate historical data are available, information can be collected at appropriate spatial and temporal scales, organizations are committed to use indicator information in the decision-making process, and indicators can effectively guide behavior toward more sustainable practices. 相似文献
126.
127.
Matthew R. House Marvin R. Pyles Dale White 《Journal of the American Water Resources Association》2005,41(1):209-217
ABSTRACT: Stream crossings designed to simulate a natural streambed inside a culvert are commonly used to meet criteria where fish passage is required. Currently, there has been little research that quantitatively examines the flow patterns within these streambed simulation culverts. A model is presented that estimates the percent of a cross section that is within the swimming ability of juvenile fish developed from velocity measurements on first‐generation stream simulation culverts — those culverts with a continuous gravel bed. The model, developed with regression techniques, uses physical and hydraulic parameters including discharge, total cross sectional area, Froude number, and relative roughness, and was tested directly against velocity distributions computed from field measurements and in a culvert design mode. Results were favorable, although larger percentage errors exist, particularly at small flow depths. The model appears to underestimate the percent of channel cross section at or below a limiting velocity, hence it is generally conservative in design mode. 相似文献
128.
双盲测试是一种经典的测试方法,适用于测试结果依赖人的影响或解释的情况.本文记录Sandia国家实验室对MOLE可编程探测系统进行双盲测试的整个过程,包括测试准备、测试设计、测试参数设定、进行测试、测试结果分析和讨论. 相似文献
129.
Jeffrey H. Gove Stephen E. Fairweather Dale S. Solomon 《Environmental and Ecological Statistics》1994,1(2):109-120
Two mathematical programming formulations are presented which allow the determination of diameter distributions that maximize
the diameter class diversity in uneven-aged northern hardwood stands. Distributions generated from these models were found
to be comparable from a management standpoint and could be incorporated into existing linear programming models as alternative
management scenarios. The models presented here provide an initial framework for quantitatively addressing the requirements
of the US National Forest Management Act in matters of diversity in the planning process. 相似文献
130.
John A. Kronenberger Jill C. Gerberich Sarah W. Fitzpatrick E. Dale Broder Lisa M. Angeloni W. Chris Funk 《Conservation biology》2018,32(4):838-848
Human land use is fragmenting habitats worldwide and inhibiting dispersal among previously connected populations of organisms, often leading to inbreeding depression and reduced evolutionary potential in the face of rapid environmental change. To combat this augmentation of isolated populations with immigrants is sometimes used to facilitate demographic and genetic rescue. Augmentation with immigrants that are genetically and adaptively similar to the target population effectively increases population fitness, but if immigrants are very genetically or adaptively divergent, augmentation can lead to outbreeding depression. Despite well‐cited guidelines for the best practice selection of immigrant sources, often only highly divergent populations remain, and experimental tests of these riskier augmentation scenarios are essentially nonexistent. We conducted a mesocosm experiment with Trinidadian guppies (Poecilia reticulata) to test the multigenerational demographic and genetic effects of augmenting 2 target populations with 3 types of divergent immigrants. We found no evidence of demographic rescue, but we did observe genetic rescue in one population. Divergent immigrant treatments tended to maintain greater genetic diversity, abundance, and hybrid fitness than controls that received immigrants from the source used to seed the mesocosms. In the second population, divergent immigrants had a slightly negative effect in one treatment, and the benefits of augmentation were less apparent overall, likely because this population started with higher genetic diversity and a lower reproductive rate that limited genetic admixture. Our results add to a growing consensus that gene flow can increase population fitness even when immigrants are more highly divergent and may help reduce uncertainty about the use of augmentation in conservation. 相似文献