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11.
Populations subject to anthropogenic contaminants often display altered patterns of genetic variation, including decreased genetic variability. Selective pressures of contaminant exposure are also reflected in differential tolerance between genotypes. An industrial chemical spill in a major eastern Australian waterway in July 2006 resulted in altered patterns of genetic variability in a nearby population of the amphipod, Melita plumulosa for up to one year post-spill, despite the site being declared clean after 48 h. Here, we investigate the toxicant response of three mitochondrial lines naturally occurring at the impacted site by comparing survivorship and life-history trait variables following naphthalene exposure. Overall, M. plumulosa demonstrated differential survivorship between mitochondrial lines under exposure to high concentrations of naphthalene. In addition, we identified differential fecundity and frequencies of gravidity in female amphipods between the mitochondrial haplotypes examined. These findings suggest that the patterns of genetic variability previously identified may be linked with differential tolerance and/or reproductive performance between mitochondrial lineages.  相似文献   
12.
The levels of selected polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in human milk samples from the areas of Venice and Rome, primarily in order to characterize the current levels of infant exposure to PCBs and PBDEs due to breast feeding in Italy. Sixteen non-dioxin-like PCBs, including the traditional indicator congeners, and 11 PBDEs, comprising the relevant PBDE-47, PBDE-99, and PBDE-153, were determined. Congeners were selected for analysis according to their relative abundance in human tissues, toxicological relevance, and diffusion in the environment. Dietary habits of the milk donors were recorded by questionnaires; mothers of the Venice area were classified into three groups according to their consumption of local fish, molluscs, and other fishery products. Sigma(16)(PCBs) and Sigma(11)(PBDEs) (ng g(-1) fat) for the areas of Venice and Rome were respectively, 250-390 and 240, and 1.6-2.8 and 4.1. An increase of fish and fishery product consumption could not be associated with an increase of PCB and PBDE levels in milk.  相似文献   
13.
Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public.  相似文献   
14.
There are a wide variety of different herbicide treatment methods used to remove single trees. Each method (cut-stump, basal, foliar) has a unique amount of off-target disturbance that should be considered in selecting a treatment for use in management. We quantified the amount of off-target deposition that resulted from four conventional herbicide application methods: 1) basal, 2) cut-stump, 3) high-volume, hydraulic foliar, and 4) low-volume, backpack foliar. Basal and cut-stump herbicide treatments deposited up to 200 and 4000 times more herbicide (a.i. per unit area) at groundline than the low-volume and high-volume foliar treatments, respectively. On a per tree basis, basal and cut-stump treatments deposited nearly six times more total herbicide than high-volume foliar, and 68 times more than low-volume foliar. All of the herbicide deposited off-target landed within 0.6 m of the basal and cut-stump treatments, 3.7 m with the low-volume foliar, and 7.3 m with high-volume foliar methods. Off-target herbicide deposition resulted in affected areas with killed or damaged vegetation ranging in size from 0.36 m2 (cut stump) to 7.08 m2 (high-volume foliar). Deposition amounts and affected areas were greater with larger trees, compared to smaller ones. We observed that 48% of the total amount of herbicide applied per plot was deposited off-target with cut-stump treatment, compared to only 4% to 11% for the other treatments. We suspect this difference is due to applicator error with the cut-stump treatment, likely related to the type of spray device used to apply the treatment.  相似文献   
15.
/ Siting hazardous waste facilities is an extremely complex and difficult endeavor. Public aversion to the construction of these facilities in or near their community often results in concerted opposition, referred to as the NIMBY syndrome. For the most part, siting processes do not fail because of inadequate environmental or technical considerations, but because of the adversarial decision-making strategies employed by the proponents. Innovative siting processes used in the provinces of Alberta and Manitoba offer tangible evidence of the successful application of an innovative siting approach based on the principles of decentralization of decision-making authority and full and meaningful public involvement. The purpose of this paper is to evaluate four Canadian siting processes from the perspective of public participation and access to decision-making authority. Examples of siting processes related to hazardous waste management facilities are provided from the provinces of Alberta, Manitoba, British Columbia, and Ontario. Siting has evolved from approaches dominated by top-down decision making to increasing decentralized and pluralistic approaches. Focusing on social and political concerns of potentially affected communities and on the process of decision making itself are fundamental to achieving siting success. In Alberta initially, and later in Manitoba, this new "open approach" to siting has resulted in the construction of the first two comprehensive hazardous waste treatment facilities in Canada.KEY WORDS: Hazardous waste facilities; Siting methodologies; Public participation  相似文献   
16.
The Waste Isolation Pilot Plant (WIPP) is the only operating deep underground geologic nuclear repository in the United States. It is located in southeastern New Mexico, approximately 655 m (2150 ft) below the surface of the Earth in a bedded Permian evaporite salt formation. This mined geologic repository is designed for the safe disposal of transuranic (TRU) wastes generated from the US defense program. Aerosol and soil samples have been collected near the WIPP site to investigate the sources of plutonium in the WIPP environment since the late 1990s, well before WIPP received its first shipment. Activities of (238)Pu, (239+240)Pu and (241)Am were determined by alpha spectrometry following a series of chemical separations. The concentrations of Al and U were determined in a separate set of samples by inductively coupled plasma mass spectrometry. The annual airborne concentrations of (239+240)Pu during the period from 1998 to 2010 show no systematic interannual variations. However, monthly (239+240)Pu particulate concentrations show a typical seasonal variation with a maximum in spring, the time when strong and gusty winds frequently give rise to blowing dust. Resuspension of soil particles containing weapons fallout is considered to be the predominant source of plutonium in the WIPP area. Further, this work characterizes the source, temporal variation and its distribution with depth in a soil profile to evaluate the importance of transport mechanisms affecting the fate of these radionuclides in the WIPP environment. The mean (137)Cs/(239+240)Pu, (241)Am/(239+240)Pu activity ratio and (240)Pu/(239)Pu atom ratio observed in the WIPP samples are consistent with the source being largely global fallout. There is no evidence of any release from the WIPP contributing to radionuclide concentrations in the environment.  相似文献   
17.
In this study, we evaluated the European Space Agency Climate Change Initiative soil moisture product v02.1 (ESA CCI SM v02.1) using in situ observations collected at 547 stations in China from 1991 to 2013. A conventional validation was first conducted, and the triple collocation errors of ESA CCI SM and the European Centre for Medium Range Weather Forecasting reanalysis data were approximately 0.053 and 0.050 m3/m3, respectively. To obtain more reliable validation results, the average soil moisture of the in situ observations per ESA CCI SM pixel was also used as the validation sites. Variance reduction factor (VRF) was adopted to quantify the accuracy of the soil moisture validation sites, and the average VRF was estimated at 4.88%. The validation results were enhanced by excluding validation sites with VRF errors greater than 5% from the statistical analysis. Although the ESA CCI SM underestimated the in situ observations with a Bias of 0.05 m3/m3, a moderately high correlation coefficient of 0.44 and a relatively small unbiased root‐mean‐square difference of 0.05 m3/m3 were observed. This study provides information on the utilization of ESA CCI SM for ecological protection, climate change, and hydrological forecasting. It also suggests the adoption of VRF for future error corrections of satellite‐based products.  相似文献   
18.
The release of radioactivity into the atmosphere from the damaged Fukushima Daiichi nuclear power plant started on March 12th, 2011. Among the various radionuclides released, iodine -131 ((131)I) and cesium isotopes ((137)Cs and (134)Cs) were transported across the Pacific Ocean and reached the United States on 17-18 March 2011. Consequently, an elevated level of fission products (131)I, (132)I, (132)Te, (134)Cs and (137)Cs were detected in air, water, and milk samples collected across the United States between March 17 and April 4, 2011. The continuous monitoring of activities over a period of 25 days and spatial variations across more than 100 sampling locations in the United States made it possible to characterize the contaminated air masses. For the entire period, the highest detected activity values ranged from less than 1 m Bq m(-3) to 31 m Bq m(-3) for the particulate (131)I, and up to 96 m Bq m(-3) for the gaseous (131)I fraction.  相似文献   
19.
Amateur naturalists have played an important role in the study and conservation of nature since the 17th century. Today, naturalist groups make important contributions to bridge the gap between conservation science and practice around the world. We examined data from 2 regional naturalist programs to understand participant motivations, barriers, and perspectives as well as the actions they take to advance science, stewardship, and community engagement. These programs provide certification‐based natural history and conservation science training for adults that is followed by volunteer service in citizen science, education, and stewardship. Studies in California and Virginia include quantitative and qualitative evaluation data collected through pre‐ and postcourse surveys, interviews, and long‐term tracking of volunteer hours. Motivations of participants focused on learning about the local environment and plants and animals, connecting with nature, becoming certified, and spending time with people who have similar interests. Over half the participants surveyed were over 50 years old, two‐thirds were women, and a majority reported household incomes of over $50,000 (60% in California, 85% in Virginia), and <20% of those surveyed in both states described themselves as nonwhite. Thus, these programs need to improve participation by a wider spectrum of the public. We interviewed younger and underrepresented adults to examine barriers to participation in citizen science. The primary barrier was lack of time due to the need to work and focus on career advancement. Survey data revealed that participants’ ecological knowledge, scientific skills, and belief in their ability to address environmental issues increased after training. Documented conservation actions taken by the participants include invasive plant management, habitat restoration, and cleanups of natural areas and streams. Long‐term data from Virginia on volunteer hours dedicated to environmental citizen science show an increase from 14% in 2007 to 32% in 2014. In general, participants in the naturalist programs we examined increased their content knowledge about ecosystems, had greater confidence in conserving them, and continued to engage as citizen scientists after completing the program.  相似文献   
20.
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