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691.
The extensive literature on environmental justice has, by now, well defined the essential ingredients of cumulative risk,
namely, incompatible land uses and vulnerability. Most problematic is the case when risk is produced by a large aggregation
of small sources of air toxics. In this article, we test these notions in an area of Southern California, Southeast Los Angeles
(SELA), which has come to be known as Asthmatown. Developing a rapid risk mapping protocol, we scan the neighborhood for small
potential sources of air toxics and find, literally, hundreds of small point sources within a 2-mile radius, interspersed
with residences. We also map the estimated cancer risks and noncancer hazard indices across the landscape. We find that, indeed,
such large aggregations of even small, nondominant sources of air toxics can produce markedly elevated levels of risk. In
this study, the risk profiles show additional cancer risks of up to 800 in a million and noncancer hazard indices of up to
200 in SELA due to the agglomeration of small point sources. This is significant (for example, estimates of the average regional
point-source-related cancer risk range from 125 to 200 in a million). Most importantly, if we were to talk about the risk
contour as if they were geological structures, we would observe not only a handful of distinct peaks, but a general “mountain
range” running all throughout the study area, which underscores the ubiquity of risk in SELA. Just as cumulative risk has
deeply embedded itself into the fabric of the place, so, too, must intervention seek to embed strategies into the institutions
and practices of SELA. This has implications for advocacy, as seen in a recently initiated participatory action research project
aimed at building health research capacities into the community in keeping with an ethic of care. 相似文献
692.
Fedorov N. I. Martynenko V. B. Zhigunova S. N. Mikhailenko O. I. Shendel’ G. V. Naumova L. G. 《Russian Journal of Ecology》2021,52(2):118-125
Russian Journal of Ecology - Changes in the distribution of broadleaf tree species—Tilia cordata Mill., Quercus robur L., Acer platanoides L., and Ulmus glabra Huds.—in the central part... 相似文献
693.
Robert A. Montgomery Madeline Carr Charlie R. Booher Abigail M. Pointer Brendan M. Mitchell Natalie Smith Keegan Calnan Georgina M. Montgomery Mordecai Ogada Daniel B. Kramer 《Conservation biology》2020,34(4):915-924
In November 1928, Theodore Jr. and Kermit Roosevelt led an expedition to China with the expressed purpose of being the first Westerners to kill the giant panda (Ailuropoda melanoleuca). The expedition lasted 8 months and resulted in the brothers shooting a giant panda in the mountains of Sichuan Province. Given the concurrent attention in the popular press describing this celebrated expedition, the giant panda was poised to be trophy hunted much like other large mammals around the world. Today, however, the killing of giant pandas, even for the generation of conservation revenue, is unthinkable for reasons related to the species itself and the context, in time and space, in which the species was popularized in the West. We found that the giant panda's status as a conservation symbol, exceptional charisma and gentle disposition, rarity, value as a nonconsumptive ecotourism attraction, and endemism are integral to the explanation of why the species is not trophy hunted. We compared these intrinsic and extrinsic characteristics with 20 of the most common trophy-hunted mammals to determine whether the principles applying to giant pandas are generalizable to other species. Although certain characteristics of the 20 trophy-hunted mammals aligned with the giant panda, many did not. Charisma, economic value, and endemism, in particular, were comparatively unique to the giant panda. Our analysis suggests that, at present, exceptional characteristics may be necessary for certain mammals to be excepted from trophy hunting. However, because discourse relating to the role of trophy hunting in supporting conservation outcomes is dynamic in both science and society, we suspect these valuations will also change in future. 相似文献
694.
695.
Environmental Fluid Mechanics - A series of experiments were conducted to quantify the dynamics of a filling box driven by a line plume that spans the full width of the enclosure. Three... 相似文献
696.
Andrew S. Jones Allan A. Andales Jos L. Chvez Cullen McGovern Garvey E.B. Smith Olaf David Steven J. Fletcher 《Journal of the American Water Resources Association》2020,56(2):201-211
We apply predictive weather metrics and land model sensitivities to improve the Colorado State University Water Irrigation Scheduler for Efficient Application (WISE). WISE is an irrigation decision aid that integrates environmental and user information for optimizing water use. Rainfall forecasts and verification performance metrics are used to estimate predictive rainfall probabilities that are used as input data within the irrigation decision aid. These input data errors are also used within a land model sensitivity study to diagnose important prognostic water movement behaviors for irrigation tool development purposes simultaneously performing the analysis in space and time. Thus, important questions such as “how long can a crop water application be delayed while maintaining crop yield production?” are addressed by evaluating crop growth stage interactions as a function of soil depth (i.e., space), rainfall events (i.e., time), and their probabilistic uncertainties. Editor’s note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
697.
Cuyler Christine Rowell Janice Adamczewski Jan Anderson Morgan Blake John Bretten Tord Brodeur Vincent Campbell Mitch Checkley Sylvia L. Cluff H. Dean Côté Steeve D. Davison Tracy Dumond Mathieu Ford Barrie Gruzdev Alexander Gunn Anne Jones Patrick Kutz Susan Leclerc Lisa-Marie Mallory Conor Mavrot Fabien Mosbacher Jesper Bruun Okhlopkov Innokentiy Mikhailovich Reynolds Patricia Schmidt Niels Martin Sipko Taras Suitor Mike Tomaselli Matilde Ytrehus Bjørnar 《Ambio》2020,49(3):805-819
Ambio - Muskoxen (Ovibos moschatus) are an integral component of Arctic biodiversity. Given low genetic diversity, their ability to respond to future and rapid Arctic change is unknown, although... 相似文献
698.
The Canadian Forest Fire Danger Rating System (CFFDRS) is used daily across Canada for evaluating forest fire danger. Fuel-type information is one of the inputs required by the models used in the CFFDRS. In this project, three fuel-type maps with a 25 m resolution were produced for a pilot study area located in Alberta using land cover only; land cover and biomass; and, land cover, biomass and leaf area index data derived from satellite imagery. The relationships between inputs and fuel types were determined mainly by the opinions of forest fire scientists and incorporated into a computer program using fuzzy set methodology. Not all the CFFDRS fuel types could be distinguished using these inputs; three of the coniferous types had to be grouped into one common fuel type. Overall accuracy was between 74 and 83% based on ground-truth comparisons. The most accurate map resulted from land cover and biomass data. Detailed accuracy assessment indicated that the overall accuracy increased up to 86% if ambiguous fuel type identification was considered. No combination of inputs was able to define a fuel type with absolute certainty, which is a reflection of differing expert opinions and the small number of inputs used to produce the maps. 相似文献
699.
Steroid estrogens such as estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) have been suspected to be the main contaminants, which can affect the endocrine system of animals. Many authors have investigated these chemicals in the domestic wastewater treatment plants (WTP). However, wastewater from industries producing steroid contraceptives has not got ample attention. From the environmental point of view, the four steroids are very significant because even very low concentrations (ng/L) can cause reproductive disturbances in human, livestock and wildlife. The main purpose of the present investigation was to develop an analytical method for the determination of the four steroid estrogens present in WTP of a pharmacy factory, mainly producing contraceptive medicine in Beijing, China. Analysis was performed by solid-phase extraction (SPE) system and liquid chromatography combined with tandem mass spectrometry (LC/MS/MS). The average recoveries from effluent samples ranged from 88% to 103% and the precision of the method ranged from 9% to 4%. Based on 0.5-L wastewater samples, the limit of quantification (LOQ) was determined at 0.7 ng/L for E1, 0.8 for E2, 0.9 ng/L for E3, and 0.5 ng/L for EE2 in influent, and 1.0 ng/L for E2 and EE2, and 2.0 ng/L for E1 and E3 in effluent. In the influent samples, average concentrations of 80, 85, 73 and 155 ng/L were determined for E1, E2, E3 and EE2, respectively, showing that they were removed in this WTP to the extent of 79, 73, 85 and 67%, respectively. 相似文献
700.
Zhang Y Ruan L Fasola M Boncompagni E Dong Y Dai N Gandini C Orvini E Ruiz X 《Environmental monitoring and assessment》2006,118(1-3):355-368
The rapidly developing Asian countries may face threatening environmental contamination, that however remains largely unassessed.
We studied persistent trace elements in three wetlands, Poyang Lake, relatively unpolluted, and Tai Lake, and Pearl River
Delta, selected as hotspots of pollution in Central China. We adopted as indicator the Little Egret, a widespread colonial
waterbird, and during 1999 and 2000 we collected and analysed the same samples as for a parallel study we conducted in Pakistan,
e.g. eggs, body feathers of chicks, prey spontaneously regurgitated by the chicks, and sediments at the areas most used by
foraging egrets. The levels of trace-metals at our three study areas were similar, or within the range, of those found in
the few other studies for East Asia, with few exceptions. The concentrations of the various elements were below the threshold
that may affect the survival or reproduction of the birds, and even the highest concentrations relative to background, i.e.
Se in eggs, and Hg in feathers at Pearl Delta, do not pose toxic hazards. In sediments, the levels of trace elements were
lower than the critical levels assumed for contaminated soil, except for alarming high levels of As at Poyang. These results
do not confirm our expectation, that Poyang was relatively uncontaminated, while Tai and Pearl were polluted. Although trace
metal concentration differed significantly among the three study areas, these differences were minor and were not consistent
among elements and samples. The bioaccumulation ratios from sediments through prey, feather and egg, were consistent with
our previous findings for Pakistan. Only Hg exhibited high bioaccumulation, while Se and Zn had low accumulation, and the
other elements no accumulation. This reasserts that feathers of predators such as egrets, may be more sensitive indicators
of environmental contamination for the elements subject to bioaccumulation, whereas the sediments or the organisms low in
the food chain are better indicators for the other elements. 相似文献