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81.
Rodhouse TJ Ormsbee PC Irvine KM Vierling LA Szewczak JM Vierling KT 《Ecological applications》2012,22(4):1098-1113
Bats face unprecedented threats from habitat loss, climate change, disease, and wind power development, and populations of many species are in decline. A better ability to quantify bat population status and trend is urgently needed in order to develop effective conservation strategies. We used a Bayesian autoregressive approach to develop dynamic distribution models for Myotis lucifugus, the little brown bat, across a large portion of northwestern USA, using a four-year detection history matrix obtained from a regional monitoring program. This widespread and abundant species has experienced precipitous local population declines in northeastern USA resulting from the novel disease white-nose syndrome, and is facing likely range-wide declines. Our models were temporally dynamic and accounted for imperfect detection. Drawing on species-energy theory, we included measures of net primary productivity (NPP) and forest cover in models, predicting that M. lucifugus occurrence probabilities would covary positively along those gradients. Despite its common status, M. lucifugus was only detected during -50% of the surveys in occupied sample units. The overall naive estimate for the proportion of the study region occupied by the species was 0.69, but after accounting for imperfect detection, this increased to -0.90. Our models provide evidence of an association between NPP and forest cover and M. lucifugus distribution, with implications for the projected effects of accelerated climate change in the region, which include net aridification as snowpack and stream flows decline. Annual turnover, the probability that an occupied sample unit was a newly occupied one, was estimated to be low (-0.04-0.14), resulting in flat trend estimated with relatively high precision (SD = 0.04). We mapped the variation in predicted occurrence probabilities and corresponding prediction uncertainty along the productivity gradient. Our results provide a much needed baseline against which future anticipated declines in M. lucifugus occurrence can be measured. The dynamic distribution modeling approach has broad applicability to regional bat monitoring efforts now underway in several countries and we suggest ways to improve and expand our grid-based monitoring program to gain robust insights into bat population status and trend across large portions of North America. 相似文献
82.
83.
Sharmishtha Dattagupta Meredith Redding Kathryn Luley Charles Fisher 《Marine Biology》2009,156(4):779-786
Lamellibrachia luymesi and Seepiophila jonesi are co-occurring species of vestimentiferan tubeworms found at hydrocarbon seepage sites on the upper Louisiana slope of
the Gulf of Mexico. Like all vestimentiferans, they rely on internal sulfide-oxidizing symbiotic bacteria for nutrition. These
symbionts produce hydrogen ions as a byproduct of sulfide oxidation, which the host tubeworm needs to eliminate to prevent
acidosis. The hydrothermal vent tubeworm Riftia pachyptila uses a high activity of P- and V-type H+-ATPases located in its plume epithelium to excrete protons. Unlike R. pachyptila, the seep species grow a posterior root, which they can use in addition to their plumes as a nutrient exchange surface. In
this study we measured the ATPase activities of plume and root tissues collected from L. luymesi and S. jonesi, and used a combination of inhibitors to determine the relative activities of P- and V-type H+-ATPases. We found that the total H+-ATPase activity of their plumes was approximately 14 μmol h−1 g−1 wet weight, and that of their roots was between 5 and 7 μmol h−1 g−1 wet weight. These activities were more than ten times lower than those measured in R. pachyptila. We suggest that seep tubeworms might use passive channels to eliminate protons across their roots, in addition to ATP-dependant
proton pumps located in their plumes and roots. In addition, we found strong differences between the types of ATPase activities
in the plumes of L. luymesi and S. jonesi. While the H+-ATPase activity of L. luymesi plumes is dominated by P-type ATPases, S. jonesi has an unusually high activity of V-type H+-ATPases. We suggest that S. jonesi relies on its high V-type H+-ATPase activity to drive carbon dioxide uptake across its plume surface. L. luymesi, on the other hand, might rely partially on bicarbonate uptake across its root. 相似文献
84.
Tolerance to hyposalinity of the scleractinian coral S. radians was examined in a mesocosm study. Colonies of S. radians were collected from five basins in Florida Bay, USA, which occur along a northeast-to-southwest salinity gradient. Salinity
treatments were based on historical salinity records for these basins. Photophysiology of the endosymbiont Symbiodinium spp. (maximum quantum yield; F
v/F
m) was measured as an indicator of holobiont stress to hyposalinity. Colonies from each basin were assigned four salinity treatments
[The Practical Salinity Scale (PSS) was used to determine salinity. Units are not assigned to salinity values because it is
a ratio and has no unit as defined by UNESCO (UNESCO Technical papers no. 45, IAPSO Pub. Sci. No. 32, Paris, France, 1985)]
(30, 20, 15, and 10) and salinities were reduced 2 per day from ambient (30) to simulate a natural salinity decrease. Colonies
treated with salinities of 20 and 15 showed no decrease in F
v/F
m versus controls (i.e. 30), up to 5 days after reaching their target salinity. This indicates a greater ability to withstand
reduced salinity for relatively extended periods of time in S. radians compared to other reef species. Within 1 day after salinity of 10 was reached, there was a significant reduction in F
v/F
m, indicating a critical threshold for hyposaline tolerance. At the lowest treatment salinity (10), F
v/F
m for the more estuarine, northeast-basin colonies were significantly higher than the most marine southwest-basin colonies
(Twin Key Basin). Our results suggest that historical salinity ranges within basins determine coral population salinity tolerances. 相似文献
85.
Rita Hargitai Kathryn E. Arnold Márton Herényi József Prechl János Török 《Behavioral ecology and sociobiology》2009,63(6):869-882
Offspring survival can be influenced by resources allocated to eggs, which in turn may be affected by the environmental factors
the mother experiences during egg formation. In this study, we investigated whether experimentally elevated social interactions
and number of neighbouring pairs influence yolk composition of collared flycatchers (Ficedula albicollis). Social challenge was simulated by presentation of a conspecific female. Experimental females spent more time near the cage
and produced eggs with higher androgen concentration, but local breeding density did not affect yolk androgen level. Moreover,
we found that females exposed to more intra-specific interactions and those that bred at higher density produced eggs with
smaller yolk. These females may be more constrained in foraging time due to more frequent social encounters, and there might
be increased competition for food at areas of higher density. In contrast, the present study did not reveal any evidence for
the effect of social environment on yolk antioxidant and immunoglobulin levels. However, we found that yolk lutein and immunoglobulin
concentrations were related to the female’s H/L ratio. Also, yolk lutein and α-tocopherol levels showed a seasonal increase
and were positively related to the female’s plasma carotenoid level. Mothers may incur significant costs by transferring these
compounds into the eggs, thus only females in good physiological condition and those that lay eggs later, when food is probably
more abundant, could allocate higher amounts to the eggs without compromising their defence mechanisms. Our results suggest
that environmental circumstances during egg formation can influence conditions for embryonic development. 相似文献
86.
This paper explores the crucial part that faith‐based organisations (FBOs) play in acting as intermediaries between international donors and local faith communities (LFCs) implementing humanitarian relief projects for Syrian refugees. Humanitarian responses to the mounting Syrian refugee crisis have coincided with greater collaboration between international donors and LFCs. This cooperation often is facilitated by a complex web of non‐state intermediaries at the international, national, and local level. This study probes the breadth of roles of these intermediaries, drawing on primary data from case studies of two Christian intermediaries supporting Christian LFCs as they deliver aid primarily to Muslim Syrian refugees in Jordan and Lebanon. The results of the study are connected to the wider literature on LFCs in humanitarian response, revealing how intermediaries address issues of accountability, capacity‐building, impartiality, neutrality, and professionalism. The paper concludes by offering suggestions for further research on intermediaries as key actors in the localisation of humanitarian assistance. 相似文献
87.
Kathryn J. Norlock 《Journal of Agricultural and Environmental Ethics》2010,23(1-2):29-42
Our attitudes toward human culpability for environmental problems have moral and emotional import, influencing our basic capacities for believing cooperative action and environmental repair are even possible. In this paper, I suggest that having the virtue of forgivingness as a response to environmental harm is generally good for moral character, preserving us from morally risky varieties of pessimism and despair. I define forgivingness as a forward-looking disposition based on Robin Dillon’s conception of preservative forgiveness, a preparation to be deeply and abidingly accepting yet expecting human error. As with other virtues, however, preservative forgiveness is available to some of us more than others; in the second half of this paper, I consider the deep challenge posed by rational pessimism, especially on the part of those who have been given many reasons not to hope for the very moral improvements for which they strive. I conclude that for those of us with the power roles and personal resources especially conducive to environmental activism, preservative forgiveness inclines us to remain engaged in environmental activism with fellow flawed human beings, recognizing our own mutual depredations while committing us to cooperatively respond. 相似文献
88.
Occurrence of boscalid and other selected fungicides in surface water and groundwater in three targeted use areas in the United States 总被引:3,自引:0,他引:3
Although the use of the insecticide γ-hexachlorocyclohexane (HCH) is now prohibited in many countries because of its hazardousness, stockpiles of γ-HCH still exist. In this study, we subjected γ-HCH to mechanochemical (MC) treatment with a planetary ball mill in the presence of CaO to investigate the feasibility of using this method for the treatment of γ-HCH stockpiles. We confirmed the degradation of γ-HCH and investigated the degradation mechanism. The major intermediates were identified to be 1,3,4,5,6-pentachlorocyclohexene (γ-PCCH) and chlorobenzenes (CBzs). Analysis of the steric structure of γ-HCH and identification of the degradation intermediates suggested that successive dehydrochlorination led to the formation of trichlorobenzenes. Products of further degradation (dichlorobenzenes, monochlorobenzene, and benzene) were also detected. Surprisingly, methane and ethane were also detected, which suggests cleavage of the C-C bonds of the cyclohexane ring and hydrogenation. All of the chlorine atoms in the γ-HCH could be transformed into inorganic chloride compounds by the MC treatment with CaO. Our results indicate that γ-HCH can be completely dechlorinated by MC treatment. 相似文献
89.
Carl M. Shy M.D. Dr. P.H. John P. Creason M.S. Martin E. Pearlman M.D. Kathryn E. McClain Ferris B. Benson Marion M. Young M.D. 《Journal of the Air & Waste Management Association (1995)》2013,63(8):539-545
Elementary schools in four areas of Greater Chattanooga were selected for a study of the effects of community exposure to nitrogen dioxide. One area, in close proximity to a large TNT plant, had high NO2 exposure, another had relatively high suspended particulate exposure, and two areas served as “clean” controls. The similarity of the economic levels of the High-NO2 and Control areas and the moderately lower economic level of the High-Particulate area were documented. Pollutant concentrations for NO2 gas, suspended nitrates and sulfates, total suspended particulates, and soiling index were measured at stations located within the study areas. Ventilatory performance of second-grade school children in the High-NO2 exposure area was significantly lower than the performance of children in the Control areas. The data suggested that ventilatory performance was adversely affected only when an NO2 threshold was exceeded but that above this threshold no further impairment of performance could be detected. 相似文献
90.
Leaking underground storage tank systems at service stations have resulted in tens of thousands of petroleum releases and associated groundwater chemical plumes often extending hundreds of feet off‐site. Technical and engineering approaches to assess and clean up releases from underground tanks, product lines, and dispensers using technologies such as soil vapor extraction, air sparging, biostimulation, and monitored natural attenuation are well understood and widely published throughout the literature. This article summarizes life‐cycle environmental response costs typically encountered using site‐specific cost estimation or metric‐based cost categories considering the overall complexity of site conditions: (1) simple sites where response actions require smaller scale assessments and/or remediation and have limited or no off‐site impacts; (2) average sites where response actions require larger scale assessments and/or remediation typical of petroleum releases; (3) complex sites where response actions require greater on‐site and/or off‐site remediation efforts; and (4) mega sites where petroleum plumes have impacted public or private water supplies or where petroleum vapors have migrated into occupied buildings. Associated cleanup cost estimates rely upon appropriate combinations of individual work elements and the duration of operation, maintenance, and monitoring activities. These cost estimates can be offset by state reimbursement funds, coverage in purchase agreements, and insurance policies. A case study involving a large service station site portfolio illustrates the range of site complexity and life‐cycle environmental response costs. © 2014 Wiley Periodicals, Inc. 相似文献