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51.
Steven N. Chillrud Richard F. Bopp James M. Ross Damon A. Chaky Sidney Hemming Edward L. Shuster H. James Simpson Frank Estabrooks 《Water, Air, & Soil Pollution: Focus》2004,4(2-3):469-482
Radionuclide, radiogenic lead isotope and trace metal analyses on fine-grained sediment cores collected along 160 km of the upper and tidal Hudson River were used to examine temporal trends of contaminant loadings and to develop radiogenic lead isotopes both as a stratigraphic tool and as tracers for resolving decadal particle transport fluxes. Very large inputs of Cd, Sb, Pb, and Cr are evident in the sediment record, potentially from a single manufacturing facility. The total range in radiogenic lead isotope ratios observed in well-dated cores collected about 24 km downstream of the plant is large (e.g., maximum difference in 206Pb/207Pb is 10%), characterized by four major shifts occurring in the 1950s, 1960s, 1970s and 1980s. The upper Hudson signals in Cd and radiogenic lead isotopes were still evident in sediments collected 160 km downstream in the tidal Hudson. The large magnitude and abrupt shifts in radiogenic lead isotope ratios as a function of depth provide sensitive temporal constraints that complement information derived from radionuclide analyses to significantly improve the precision of dating assignments. Application of a simple dilution model to data from paired cores suggests much larger sediment inputs in one section of the river than previously reported, suggesting particle influxes to the Hudson have been underestimated. 相似文献
52.
Recently, integration of personality traits into a ‘pace-of-life syndrome’ (POLS) context has been advocated. To be able to understand how an individual’s behavioural, physiological and life history traits may coevolve, we need to jointly quantify these traits in order to study their covariance. Few studies have established links between personality and immunity properties of an individual. We here examined covariation of a measure of skeletal size (tarsus length), three behavioural traits (activity, handling aggression and breath rate) and two immunological traits (IgG level and haematocrit), in 592 wild caught blue tits. Many individuals (201) were tested more than once, allowing quantification of individual consistency of all traits and partition of the covariances between the traits, using a multivariate mixed model, into between individual and residual covariances. We find individual consistency of all behavioural traits, indicating that these capture aspects of blue tit adult personality and also the physiological measures are repeatable. Contrary to the POLS expectation, we find no overall significant individual level correlation structure between these traits and a factor analytical approach confirmed that between individual correlations across traits were not due to a common (POLS) factor or driven by size (tarsus length). Based on a published power study, we conclude that there is no common syndrome of individual level covariance between personality and physiological traits in wild blue tits or that the effect sizes, such a syndrome generates, are too low (r?<?0.3) to detect. Future field-based work should be designed to explore low effect sizes and strive to measure specific traits whose involvement is implicated to have large effect sizes as based on, e.g. laboratory findings. 相似文献
53.
Damon M. Hall Gerardo R. Camilo Rebecca K. Tonietto Jeff Ollerton Karin Ahrné Mike Arduser John S. Ascher Katherine C. R. Baldock Robert Fowler Gordon Frankie Dave Goulson Bengt Gunnarsson Mick E. Hanley Janet I. Jackson Gail Langellotto David Lowenstein Emily S. Minor Stacy M. Philpott Simon G. Potts Muzafar H. Sirohi Edward M. Spevak Graham N. Stone Caragh G. Threlfall 《Conservation biology》2017,31(1):24-29
Research on urban insect pollinators is changing views on the biological value and ecological importance of cities. The abundance and diversity of native bee species in urban landscapes that are absent in nearby rural lands evidence the biological value and ecological importance of cities and have implications for biodiversity conservation. Lagging behind this revised image of the city are urban conservation programs that historically have invested in education and outreach rather than programs designed to achieve high‐priority species conservation results. We synthesized research on urban bee species diversity and abundance to determine how urban conservation could be repositioned to better align with new views on the ecological importance of urban landscapes. Due to insect pollinators’ relatively small functional requirements—habitat range, life cycle, and nesting behavior—relative to larger mammals, we argue that pollinators put high‐priority and high‐impact urban conservation within reach. In a rapidly urbanizing world, transforming how environmental managers view the city can improve citizen engagement and contribute to the development of more sustainable urbanization. 相似文献
54.
Edward C. Krug Allen S. Lefohn 《Journal of the Air & Waste Management Association (1995)》2013,63(6):846-854
In order to determine what effects human activities have on natural processes, it is important to thoroughly understand those processes. Unfortunately, we know little about what natural processes are operating, and even less about how they have functioned historically. This paper discusses the importance of natural processes in affecting surface water acidification and the necessity for developing quantitative estimates of natural, as well as anthropogenic, contributions to the acidification of surface waters. A review of the literature and the analysis of chemistry data from six limed lakes in New York and Massachusetts have identified a number of possible processes that may play important roles in acidifying surface waters. At present, these processes are poorly understood and require further research. Once we have such knowledge, we will be able to clearly see the effects of human activities on natural processes and modify those activities in ways that will mitigate negative impact in a predictable manner. 相似文献
55.
Christian Albert Mario Brillinger Paulina Guerrero Sarah Gottwald Jennifer Henze Stefan Schmidt Edward Ott Barbara Schrter 《Ambio》2021,50(8):1446
Nature-based solutions (NBS) find increasing attention as actions to address societal challenges through harnessing ecological processes, yet knowledge gaps exist regarding approaches to landscape planning with NBS. This paper aims to provide suggestions of how planning NBS can be conceptualized and applied in practice. We develop a framework for planning NBS by merging insights from literature and a case study in the Lahn river landscape, Germany. Our framework relates to three key criteria that define NBS, and consists of six steps of planning: Co-define setting, Understand challenges, Create visions and scenarios, Assess potential impacts, Develop solution strategies, and Realize and monitor. Its implementation is guided by five principles, namely Place-specificity, Evidence base, Integration, Equity, and Transdisciplinarity. Drawing on the empirical insights from the case study, we suggest suitable methods and a checklist of supportive procedures for applying the framework in practice. Taken together, our framework can facilitate planning NBS and provides further steps towards mainstreaming.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01365-1) contains supplementary material, which is available to authorized users. 相似文献
56.
Edward D. Frank Amgad Elgowainy Jeongwoo Han Zhichao Wang 《Mitigation and Adaptation Strategies for Global Change》2013,18(1):137-158
Algae biomass is an attractive biofuel feedstock when grown with high productivity on marginal land. Hydrothermal liquefaction (HTL) produces more oil from algae than lipid extraction (LE) does because protein and carbohydrates are converted, in part, to oil. Since nitrogen in the algae biomass is incorporated into the HTL oil, and since lipid extracted algae for generating heat and electricity are not co-produced by HTL, there are questions regarding implications for emissions and energy use. We studied the HTL and LE pathways for renewable diesel (RD) production by modeling all essential operations from nutrient manufacturing through fuel use. Our objective was to identify the key relationships affecting HTL energy consumption and emissions. LE, with identical upstream growth model and consistent hydroprocessing model, served as reference. HTL used 1.8 fold less algae than did LE but required 5.2 times more ammonia when nitrogen incorporated in the HTL oil was treated as lost. HTL RD had life cycle emissions of 31,000 gCO2 equivalent (gCO2e) compared to 21,500 gCO2e for LE based RD per million BTU of RD produced. Greenhouse gas (GHG) emissions increased when yields exceeded 0.4 g HTL oil/g algae because insufficient carbon was left for biogas generation. Key variables in the analysis were the HTL oil yield, the hydrogen demand during upgrading, and the nitrogen content of the HTL oil. Future work requires better data for upgrading renewable oils to RD and requires consideration of nitrogen recycling during upgrading. 相似文献
57.
(E)-6,10-dimethyl-5,9-undecadien-2-ol (geranyl acetol), termed here fuscol, was identified as a male-produced pheromone emitted
by Tetropium fuscum (F.) and Tetropium cinnamopterum Kirby. In field experiments, traps baited with synthetic fuscol alone were not significantly attractive, but the combination
of fuscol plus host volatiles (a synthetic blend of monoterpenes plus ethanol) attracted significantly more male and female
T. fuscum and female T. cinnamopterum than did host volatiles alone. This is the first homoterpenoid alcohol to be described in the Cerambycidae, and the first
pheromone reported from the sub-family Spondylidinae. 相似文献
58.
Methane and carbon dioxide emission in a two-phase olive oil mill sludge windrow pile during composting 总被引:1,自引:0,他引:1
Manios T Maniadakis K Boutzakis P Naziridis Y Lasaridi K Markakis G Stentiford EI 《Waste management (New York, N.Y.)》2007,27(9):1092-1098
The aim of this work was to make some preliminary evaluations on CO(2) and CH(4) emissions during composting of two-phase olive oil mill sludge (OOMS). OOMS, olive tree leaves (OTL) and shredded olive tree branches (OTB) were used as feedstock for Pile I and Pile II with a 1:1:1 and 1:1:2v/v ratio, respectively. Each pile was originally 1.2m high, 2.0m wide and approximately 15.0m long. Four 500 ml volume glass funnels were inverted and introduced in each pile, two in the core (buried 50-60 cm from the surface) and two near the surface under a thin 10-15 cm layer of the mixture. Thin (0.5 cm diameter) plastic, 80 cm long tubes were connected to the funnels. A mobile gas analyser (GA2000) was used to measure the composition (by volume) of O2, CO2 and CH4 on a daily basis. The funnels were removed prior to each turning and reinserted afterwards. From each pair of funnels (core and surface) of both piles, one was kept closed between samplings. Two way ANOVA was used to test differences between piles and among the tubes. Post hoc Tukey tests were also used to further investigate these differences. There was a significant difference (at p<0.001) in the two piles for all three gases. The average concentrations of O2, CO2 and CH4 in Pile I, from all four funnels was 16.86%, 3.89% and 0.25%, respectively, where for Pile II the average values were 18.07%, 2.38% and 0.04%, respectively. The presence of OOMS in larger amounts in Pile I (resulting in more intense decomposing phenomena), and the larger particle size of OTB in Pile II (resulting in increasing porosity) are the probable causes of these significant differences. Samples from open funnels presented lower, but not significantly lower, O2 composition (higher for CO2 and CH4) in comparison with closed funnels in both depths and both piles. Not significant were also the different mean gas compositions between core and surface funnels in the same pile. 相似文献
59.
60.
Research suggests that previous, current, and prospective extractive industry activities influence perceptions of new development. Studies that have drawn this conclusion, however, have usually focused on specific projects in specific communities. Here, these factors are examined on an aggregate, national scale. Combining geospatial data on extractive industry activities and survey data from a nationally representative sample (N = 1061), the influence of extractive industry activities on support for fracking is studied. While limited evidence is found for the impact of proximity to oil and gas wells or production on support for fracking, employment levels in the natural resources and mining sector in the respondent’s county and residence in an area experiencing active oil and gas development significantly increase support for fracking. The results highlight the role of spatial and community factors in shaping support for energy development. 相似文献