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171.
Reyer Christopher P.O Otto Ilona M. Adams Sophie Albrecht Torsten Baarsch Florent Cartsburg Matti Coumou Dim Eden Alexander Ludi Eva Marcus Rachel Mengel Matthias Mosello Beatrice Robinson Alexander Schleussner Carl-Friedrich Serdeczny Olivia Stagl Judith 《Regional Environmental Change》2017,17(6):1639-1650
Regional Environmental Change - This paper synthesizes what is known about the physical and biophysical impacts of climate change and their consequences for societies and development under... 相似文献
172.
Jerrold L Belant Knut Kielland Erich H Follmann Layne G Adams 《Ecological applications》2006,16(6):2333-2343
The fundamental niche of a species is rarely if ever realized because the presence of other species restricts it to a narrower range of ecological conditions. The effects of this narrower range of conditions define how resources are partitioned. Resource partitioning has been inferred but not demonstrated previously for sympatric ursids. We estimated assimilated diet in relation to body condition (body fat and lean and total body mass) and reproduction for sympatric brown bears (Ursus arctos) and American black bears (U. americanus) in south-central Alaska, 1998-2000. Based on isotopic analysis of blood and keratin in claws, salmon (Oncorhynchus spp.) predominated in brown bear diets (> 53% annually) whereas black bears assimilated 0-25% salmon annually. Black bears did not exploit salmon during a year with below average spawning numbers, probably because brown bears deterred black bear access to salmon. Proportion of salmon in assimilated diet was consistent across years for brown bears and represented the major portion of their diet. Body size of brown bears in the study area approached mean body size of several coastal brown bear populations, demonstrating the importance of salmon availability to body condition. Black bears occurred at a comparable density (mass:mass), but body condition varied and was related directly to the amount of salmon assimilated in their diet. Both species gained most lean body mass during spring and all body fat during summer when salmon were present. Improved body condition (i.e., increased percentage body fat) from salmon consumption reduced catabolism of lean body mass during hibernation, resulting in better body condition the following spring. Further, black bear reproduction was directly related to body condition; reproductive rates were reduced when body condition was lower. High body fat content across years for brown bears was reflected in consistently high reproductive levels. We suggest that the fundamental niche of black bears was constrained by brown bears through partitioning of food resources, which varied among years. Reduced exploitation of salmon caused black bears to rely more extensively on less reliable or nutritious food sources (e.g., moose [Alces alces], berries) resulting in lowered body condition and subsequent reproduction. 相似文献
173.
174.
Correlating seabird movements with ocean winds: linking satellite telemetry with ocean scatterometry
Satellite telemetry studies of the movements of seabirds are now common and have revealed impressive flight capabilities and
extensive distributions among individuals and species at sea. Linking seabird movements with environmental conditions over
vast expanses of the world’s open ocean, however, remains difficult. Seabirds of the order Procellariiformes (e.g., petrels,
albatrosses, and shearwaters) depend largely on wind and wave energy for efficient flight. We present a new method for quantifying
the movements of far-ranging seabirds in relation to ocean winds measured by the SeaWinds scatterometer onboard the QuikSCAT
satellite. We apply vector correlation (as defined by Crosby et al. in J Atm Ocean Tech 10:355–367, 1993) to evaluate how the trajectories (ground speed and direction) for five procellariiform seabirds outfitted with satellite
transmitters are related to ocean winds. Individual seabirds (Sooty Shearwater, Pink-footed Shearwater, Hawaiian Petrel, Grey-faced
Petrel, and Black-footed Albatross) all traveled predominantly with oblique, isotropic crossing to quartering tail-winds (i.e.,
105–165° in relation to birds’ trajectory). For all five seabirds, entire track line trajectories were significantly correlated
with co-located winds. Greatest correlations along 8-day path segments were related to wind patterns during birds’ directed,
long-range migration (Sooty Shearwater) as well as movements associated with mega-scale meteorological phenomena, including
Pacific Basin anticyclones (Hawaiian Petrel, Grey-faced Petrel) and eastward-propagating north Pacific cyclones (Black-footed
Albatross). Wind strength and direction are important factors related to the overall movements that delineate the distribution
of petrels at sea. We suggest that vector correlation can be used to quantify movements for any marine vertebrate when tracking
and environmental data (winds or currents) are of sufficient quality and sample size. Vector correlation coefficients can
then be used to assess population—or species-specific variability and used to test specific hypotheses related to how animal
movements are associated with fluid environments. 相似文献
175.
Substance use and functional impairment among adolescents directly exposed to the 2001 World Trade Center attacks 总被引:1,自引:0,他引:1
Claude M. Chemtob Yoko Nomura Louis Josephson Richard E. Adams Lloyd Sederer 《Disasters》2009,33(3):337-352
The relationship between exposure to the World Trade Center (WTC) attacks, increased substance use, functional impairment and mental health service use, controlling for depression and post-traumatic stress disorder, was assessed through an in-school survey of directly exposed students (N = 1040) attending the five middle and five high schools nearest the WTC. The survey was conducted 18 months after the attacks. Students with one WTC exposure risk factor had a five-fold increase in substance use, while those with three or more exposure risks had a nearly 19-fold increase. Increased substance use was associated with impaired school work, school behaviour and grades. Students reporting increased substance use were nearly twice as likely to want help but were no more likely than asymptomatic students to receive services. Adolescents reporting increased substance use, without co-morbidity, were less likely to receive psychological services than others. Attention to the needs of substance-using adolescents exposed to disaster is needed. 相似文献
176.
Patricia A. Fair Hing-Biu Lee Jeff Adams Colin Darling Grazina Pacepavicius Mehran Alaee Gregory D. Bossart Natasha Henry Derek Muir 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2248-2254
The presence of triclosan, a widely-used antibacterial chemical, is currently unknown in higher trophic-level species such as marine mammals. Blood plasma collected from wild bottlenose dolphins (Tursiops truncatus) in Charleston, SC (CHS) (n = 13) and Indian River Lagoon, FL (IRL) (n = 13) in 2005 was analyzed for triclosan. Plasma concentrations in CHS dolphins ranged from 0.12 to 0.27 ng/g wet weight (mean 0.18 ng/g), with 31% of the sampled individuals having detectable triclosan. The mean IRL dolphin plasma concentrations were 0.072 ng/g wet weight (range 0.025–0.11 ng/g); 23% of the samples having detectable triclosan. In the CHS area, triclosan effluent values from two WWTP were both 190 ng/L and primary influents were 2800 ng/L and 3400 ng/L. Triclosan values in CHS estuarine surface water samples averaged 7.5 ng/L (n = 18) ranging from 4.9 to 14 ng/L. This is the first study to report bioaccumulation of anthropogenic triclosan in a marine mammal highlighting the need for further monitoring and assessment. 相似文献
177.
Our challenge was to address future directions in air quality research that involve economic issues. The paper outlines the role of economics in the evaluation of air pollution impacts on environmental systems and describes existing research. We identify studies that address economic effects in the agricultural sector, in the commercial forest sector, and in unmanaged natural systems. Effects related to ozone exposure are highlighted. The summary of available research is followed by a discussion of research recommendations. Several short-term recommendations are identified that can augment some of the new research being considered by scientists. A more ambitious, long-term research project is outlined for valuing air pollution impacts in unmanaged natural environments. Specifically, the paper describes possible advantages of an 'integrated assessment' framework that more formally brings together the complex relationships that exist in both ecological and economic systems. A final section contains thoughts on the importance of education (i.e., information transfer) in the research process, especially in relation to policy. It is further noted that education should be inclusive of all members of the research team, throughout all stages of the research process. 相似文献
178.
Robin G. Adams 《Natural resources forum》1990,14(2):90-96
In the 1980s, the basic strategies of the major integrated aluminium companies have been to emphasize added investment in downstream activities at the expense of investment in smelting and raw material supply. The paper examines the rationale for such investment strategies, explores the advantages and disadvantages of downstream investment and presents projections of future demand and capacity in the industry. Overall, the industry appears to be in good shape until the mid-1990s when demand is likely to exceed currently projected capacity. 相似文献
179.
Robert B. McKusick Richard M. Adams J. Herbert Snyder 《Journal of the American Water Resources Association》1977,13(3):489-498
ABSTRACT: This paper evolved from a concern that water resource administrators and planners do not have a consistent definition of the value of goods and services of outputs from projects and programs. A more flexible approach to planning and evaluation is presented that recognizes the interaction of production and consumption through the use of commodity demand curves. Use of the concept of consumer surplus permits measurement of the differential impacts on producers' and consumers' welfare. Quadratic programming is suggested as a consistent means of quantifying these differential impacts. 相似文献
180.
George Zukovs Barry J. Adams 《Journal of the American Water Resources Association》1980,16(4):601-607
ABSTRACT: A dynamic programming model is presented for planning the optimal capacity expansion sequence of waste water treatment plants servicing sewerage systems with infiltration/inflow. The model employs a nonlinear deterministic demand function for waste water treatment plant capacity. Model output provides the optimal timing, size, and sequence for treatment plant capacity expansion projects and infiltration/inflow removal projects. An example problem is presented and solved. 相似文献