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501.
Travis Gallo Elizabeth W. Lehrer Mason Fidino R. Julia Kilgour Patrick J. Wolff Seth B. Magle 《Conservation biology》2018,32(3):638-647
For over a century there have been continual efforts to incorporate nature into urban planning. These efforts (i.e., urban reconciliation) aim to manage and create habitats that support biodiversity within cities. Given that species select habitat at different spatial scales, understanding the scale at which urban species respond to their environment is critical to the success of urban reconciliation efforts. We assessed species–habitat relationships for common bat species at 50‐m, 500‐m, and 1 km spatial scales in the Chicago (U.S.A.) metropolitan area and predicted bat activity across the greater Chicago region. Habitat characteristics across all measured scales were important predictors of silver‐haired bat (Lasionycteris noctivagans) and eastern red bat (Lasiurus borealis) activity, and big brown bat (Eptesicus fuscus) activity was significantly lower at urban sites relative to rural sites. Open vegetation had a negative effect on silver‐haired bat activity at the 50‐m scale but a positive effect at the 500‐m scale, indicating potential shifts in the relative importance of some habitat characteristics at different scales. These results demonstrate that localized effects may be constrained by broader spatial patterns. Our findings highlight the importance of considering scale in urban reconciliation efforts and our landscape predictions provide information that can help prioritize urban conservation work. 相似文献
502.
Elizabeth Otto 《The Environmentalist》2012,32(3):318-325
While modern architecture and design have often been seen as harsh and impersonal, this essay reassesses this association through a closer look at the influence of mysticism and the occult on the Bauhaus, an interwar German reform movement and school for art, craft, design, and architecture. Even as they developed their famous streamlined designs, members of the school also produced images based on alternative religions, spiritism, and other experimental and occult practices. Such images participated in a broader context of research into the otherworldly and a rediscovery of nature and the environment. Reintegrating this other history into what we know of the Bauhaus allows us to understand modernism anew, not as cold and soulless but as part of larger attempts to perceive and shape a new world that was quickly unfolding around its subjects. 相似文献
503.
Jeffrey G. Holmquist Jutta Schmidt-Gengenbach Elizabeth A. Ballenger 《Environmental management》2014,53(6):1109-1118
Assessments of vertebrate disturbance to plant and animal assemblages often contrast grazed versus ungrazed meadows or other larger areas of usage, and this approach can be powerful. Random sampling of such habitats carries the potential, however, for smaller, more intensely affected patches to be missed and for other responses that are only revealed at smaller scales to also escape detection. We instead sampled arthropod assemblages and vegetation structure at the patch scale (400–900 m2 patches) within subalpine wet meadows of Yosemite National Park (USA), with the goal of determining if there were fine-scale differences in magnitude and directionality of response at three levels of grazing intensity. Effects were both stronger and more nuanced than effects evidenced by previous random sampling of paired grazed and ungrazed meadows: (a) greater negative effects on vegetation structure and fauna in heavily used patches, but (b) some positive effects on fauna in lightly grazed patches, suggested by trends for mean richness and total and population abundances. Although assessment of disturbance at either patch or landscape scales should be appropriate, depending on the management question at hand, our patch-scale work demonstrated that there can be strong local effects on the ecology of these wetlands that may not be detected by comparing larger scale habitats. 相似文献
504.
This paper explores three questions related to acceptance as a security management approach. Acceptance draws upon relationships with community members, authorities, belligerents and other stakeholders to provide consent for the presence and activities of a non‐governmental organisation (NGO), thereby reducing threats from these actors. Little is documented about how NGOs gain and maintain acceptance, how they assess and monitor the presence and degree of acceptance, or how they determine whether acceptance is effective in a particular context. Based on field research conducted in April 2011 in Kenya, South Sudan and Uganda, we address each of these three issues and argue that acceptance must be actively sought as both a programme and a security management strategy. In the paper we delineate elements common to all three contexts as well as missed opportunities, which identify areas that NGOs can and should address as part of an acceptance approach. 相似文献
505.
506.
Determining the minimum area required to sustain populations has a long history in theoretical and conservation biology. Correlative approaches are often used to estimate minimum area requirements (MARs) based on relationships between area and the population size required for persistence or between species’ traits and distribution patterns across landscapes. Mechanistic approaches to estimating MAR facilitate prediction across space and time but are few. We used a mechanistic MAR model to determine the critical minimum patch size (CMP) for the Baltimore checkerspot butterfly (Euphydryas phaeton), a locally abundant species in decline along its southern range, and sister to several federally listed species. Our CMP is based on principles of diffusion, where individuals in smaller patches encounter edges and leave with higher probability than those in larger patches, potentially before reproducing. We estimated a CMP for the Baltimore checkerspot of 0.7–1.5 ha, in accordance with trait‐based MAR estimates. The diffusion rate on which we based this CMP was broadly similar when estimated at the landscape scale (comparing flight path vs. capture‐mark‐recapture data), and the estimated population growth rate was consistent with observed site trends. Our mechanistic approach to estimating MAR is appropriate for species whose movement follows a correlated random walk and may be useful where landscape‐scale distributions are difficult to assess, but demographic and movement data are obtainable from a single site or the literature. Just as simple estimates of lambda are often used to assess population viability, the principles of diffusion and CMP could provide a starting place for estimating MAR for conservation. 相似文献
507.
Elizabeth J. Hilkert Colby Thomas M. Young Peter G. Green Jeannie L. Darby 《Journal of the American Water Resources Association》2010,46(6):1238-1254
Hilkert Colby, Elizabeth J., Thomas M. Young, Peter G. Green, and Jeannie L. Darby, 2010. Costs of Arsenic Treatment for Potable Water in California and Comparison to U.S. Environmental Protection Agency Affordability Metrics. Journal of the American Water Resources Association (JAWRA) 46(6):1238–1254. DOI: 10.1111/j.1752-1688.2010.00488.x Abstract: The United States (U.S.) federal standard for arsenic in potable water systems is only the second water quality standard in which the U.S. Environmental Protection Agency (USEPA) administrator used “discretionary authority to establish a less stringent standard” based on the results of cost-benefit analyses. Based on the findings that a “standard of 3 μg/l would be feasible but not justified,” the revised maximum contaminant level (MCL) lowered the allowable arsenic concentration from 50 to 10 μg/l in 2002. In 2009, approximately 145 systems in California were out of compliance. The objectives were to gather performance and cost data from arsenic treatment systems in California to compare with data from the USEPA demonstration sites as well as with the USEPA affordability metrics for drinking water. The median cost of compliance with the revised arsenic MCL for the 36 surveyed systems was $1.95/1,000 gallons (2008 dollars), which is 69% of the average cost of delivered tap water in the U.S. in 2008 ($2.81/1,000 gallons). Additionally, 22% of the surveyed systems in California paid more than the maximum predicted cost of compliance with the revised arsenic MCL ($5.05/1,000 gallons). The largest variation in cost was seen in the systems that treated <500 gpm. For the systems utilizing adsorption, systems obtained between 20 and 80% of the expected bed volumes prior to breakthrough, indicating the need for better prediction of performance. 相似文献
508.
Joshua Olusegun Okeniyi Uchechuckwu Eric Obiajulu Adedamola Oluwafisayo Ogunsanwo Nosadeba Wisdom Odiase Elizabeth Toyin Okeniyi 《Mitigation and Adaptation Strategies for Global Change》2013,18(3):325-335
The potential of CH4 (methane) greenhouse gas (GHG) emissions based on a model of prevailing behavioural pattern of livestock waste management in Nigerian local farms was investigated in this paper. Livestock waste, from Sus domesticus, pig, and Gallus domesticus, poultry, were employed as substrates in the study which uses water from a fish rearing farm as the matrix medium to simulate wastewater pool/river environment. A substrate to fish-water ratio of 1:3 by mass was used in developed laboratory-size digesting reactor system with U-tube water displacement, to facilitate volumetric readings of gas production, for each mix of the livestock waste. Volumetric readings from these, at ambient temperature conditions in the retention time of 32 days, follow the Normal probability density function, in accordance with Kolmogorov-Smirnov goodness-of-fit criteria. These readings showed that CH4-containing gas as high as 67.3?×?10?3 dm3 was produced on the 14th day from the pig and 86.8?×?10?3 dm3 on the 13th day from the poultry substrates. The overall CH4-containing gas productions of 255.4?×?10?3 dm3/kg and 323.58?×?10?3 dm3/kg were observed for the pig and the poultry substrates, respectively. A 70% scale-up analysis, modelled from these results, for the nation yield potential emission of about 4 kg CH4 (that could be as potent as 84 kg CO2-equivalent) annually. The environmental implications on global warming and possible prospects of recoverable domestic benefits from the waste through the adoption of sustainable policy of livestock waste managements for mitigating the CH4 emissions in Nigerian local farms are presented. 相似文献
509.
Megan E. Mach Elizabeth J. Sbrocco Lyndie A. Hice Tara A. Duffy David O. Conover Paul H. Barber 《Marine Biology》2011,158(3):515-530
The coastal marine environment of the Northwest Atlantic contains strong environmental gradients that create distinct marine
biogeographic provinces by limiting dispersal, recruitment, and survival. This region has also been subjected to numerous
Pleistocene glacial cycles, resulting in repeated extirpations and recolonizations in northern populations of marine organisms.
In this study, we examined patterns of genetic structure and historical demography in the Atlantic silverside, Menidia menidia, an annual marine fish with high dispersal potential but with well-documented patterns of clinal phenotypic adaptation along
the environmental gradients of the Northwest Atlantic. Contrary to previous studies indicating genetic homogeneity that should
preclude regional adaptation, results demonstrate subtle but significant (F
ST = 0.07; P < 0.0001) genetic structure among three phylogeographic regions that partially correspond with biogeographic provinces, suggesting
regional limits to gene flow. Tests for non-equilibrium population dynamics and latitudinal patterns in genetic diversity
indicate northward population expansion from a single southern refugium following the last glacial maximum, suggesting that
phylogeographic and phenotypic patterns have relatively recent origins. The recovery of phylogeographic structure and the
partial correspondence of these regions to recognized biogeographic provinces suggest that the environmental gradients that
shape biogeographic patterns in the Northwest Atlantic may also limit gene flow in M. menidia, creating phylogeographic structure and contributing to the creation of latitudinal phenotypic clines in this species. 相似文献
510.
Elizabeth K. O’Dea Edward Dwyer Valerie Cummins Dawn J. Wright 《Journal of Coastal Conservation》2011,15(4):607-627
A Coastal Web Atlas (CWA) is a valuable resource for a range of users including coastal managers as it provides easy access
to maps, spatial data, coastal information and tools. A trans-Atlantic workshop on “Potentials and Limitations of Coastal
Web Atlases”, held in Ireland in July 2006, brought together atlas developers and coastal data experts from Europe and the
United States to examine state-of-the-art developments in CWAs and future needs. This paper focuses on workshop outcomes,
including what defines a CWA and an overview of international, national, state and regional atlas case studies from both sides
of the Atlantic. Results of discussions are presented concerning issues related to design, data, technology and institutional
capacity for existing CWAs based on the collective experience of workshop participants. Directions in CWA development and
applications since the workshop are also discussed. A major outcome of the workshop was the initiation of an International
Coastal Atlas Network. The insights provided give a framework for CWA developers and a useful point of reference for coastal
managers and policy makers on atlas potentials and limitations. 相似文献