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191.
Since 1972, 10 benthic surveys and 9 static fish bioassays have been conducted to assess the impact of AVTEX Fibers, Inc. effluent on the lower South Fork of the Shenandoah River. AVTEX (formerly FMC Corp.) is a rayon and polyester fibers plant located in Front Royal, Virginia. Benthic samples were taken at four stations, one above and three below the plant discharges. Single surveys in 1972 and 1973 indicated a severe impact on the benthic community along the right side of the river, below the plant, as a result of the channelized effluent. Diversity values (¯d) were low (0–2.42) and numbers of taxa and organisms were reduced. A fish bioassay in 1973 indicated the effluent to be acutely toxic at the 34.5% level (mixture of effluent and river water). In early 1974, FMC Corp. constructed an activated sludge treatment system to reduce BOD and supplement the neutralization and chemical precipitation (zinc hydroxide and liquid-solid separation) facilities that had been used to treat waste waters since 1948. After the new equipment was placed in operation, the previously stressed area became more stable. In 1975 and 1976 the stressed area exhibited greater ¯d values (1.19–3.39) and an increased number of taxa and organisms. Bioassays showed the effluent to be acutely toxic to fish only once since 1973. The major improvements in the effluent were a 70% reduction in BOD5 and a 60% reduction in the amount of zinc entering the river. Community conditions in 1977 indicated a partial remission of improvement, probably due to drought conditions.The rehabilitation of damaged ecosystems is a process important to all biologists. An important factor in encouraging industry to participate in this activity is evidence that improved waste treatment will often have demonstrable biological benefits rather soon. As data accumulate on the recovery process it may be possible to predict the degree of rehabilitation and time required more precisely.  相似文献   
192.
ABSTRACT: The production of videotape as a product of a water resources seminar is an innovative approach to graduate education. The research effort required builds upon the traditional graduate seminar approach. The videotape production requires research effort to be focused into a coherent body of information which may be widely disseminated and effectively communicates information to the public. The use of outside speakers and field trips blends very well into the preparation of a videotape. The requriement to present the many sides of a complex water resource issue in a fair and equitable manner requires maturity and professional capability on the part of the students. The research effort requires the students to meet their professional obligation to present an objective, factual, and accurate statement of the issues studies.  相似文献   
193.
A survey of 1351 people who lived within 50 miles of one of six US Department of Energy nuclear weapon sites showed that the vast majority of residents prefer strong public health surveillance and land use controls. The sample was stratified so that the same number of responses was obtained at each site. The strongest correlates of wanting the DOE to restrict on-site activities and maintain and expand its surveillance programs were worries about DOE activities on the site, as well as how those activities could damage the off-site environment. Notably, the exceptions, that is, those who demanded less from the DOE and were not particularly worried about the DOE's activities, tended to live near the site, many worked there or knew people who did, and had high socio-economic status, and trusted the DOE. The findings are mostly, but not entirely, consistent with expectations drawn from the risk perception and organizational trust literatures. The challenge is how to establish a stewardship program that represents a consensus among state and local government, community advisory boards and the public that remediation can go on at the same time that some waste is managed on-site until suitable technologies can be safely deployed, which at some sites means 100 years or in perpetuity.  相似文献   
194.
The most critical aspect of polymerization reactors is the agitator's stop and becomes more serious when this occurs exactly at the removal of the heat load, which is generated by the reaction (exothermic). This phenomenon is typical in power-failure situations of the energy supply or because of other related problems at the plant. The objective of this work is to compare the performance of two configurations for the inhibition-injection system for vinyl chloride monomer (VCM) polymerization reactors. To determine the injection time a rigorous mathematical model was developed. From the results of this work one of the configurations was implemented in an industrial plant.  相似文献   
195.
While the contemporary biomimicry movement is associated primarily with the idea of taking Nature as model for technological innovation, it also contains a normative or ethical principle—Nature as measure—that may be treated in relative isolation from the better known principle of Nature as model. Drawing on discussions of the principle of Nature as measure put forward by Benyus (Biomimicry: innovation inspired by nature, Harper Perennial, New York, 1997) and Jackson (Consulting the genius of place: an ecological approach to a new agriculture, Counterpoint, Berkeley, 2010, Nature as measure: the selected essays of Wes Jackson, Counterpoint, Berkeley, 2011), while at the same time situating these discussions in relation to contemporary debates in the philosophy of biomimicry (Mathews in Organ Environ 24(4): 364–387, 2011; Dicks in Philos Technol, doi: 10.1007/s13347-015-0210-2, 2015; Blok and Gremmen in J Agric Environ Ethics 29(2):203–217, 2016), the aim of this paper is to explore the relation between the principle of Nature as measure and environmental ethics. This leads to the argument that mainstream formulations of environmental ethics share the common trait of seeing our ethical relation to Nature as primarily involving duties to protect, preserve, or conserve various values in Nature, and that, in doing so, they problematically either overlook or dismiss as anthropocentric the possibility that Nature may provide measures, understood in terms of ecological standards, against which our own practices, or at least some of them, may be judged—a way of thinking I call “biomimetic ethics”. The practical consequences of this argument are significant. Whereas mainstream environmental ethics has been applied above all to such issues as wilderness preservation, natural resource management, and animal rights and welfare, biomimetic ethics is applicable rather to the question of how we produce, use, and consume things, and, as such, may potentially provide the basic ethical framework required to underpin the transition to a circular, bio-based, solar economy.  相似文献   
196.
This paper applies the concept of welfare environmentality to analyse Indonesia’s emerging national and project-based incentive frameworks, a key component to the climate programme reducing emissions from deforestation and forest degradation (REDD+). The paper adapts governmentality theory to explore the rationale and design of various incentive instruments, including government institutions to disburse financial payments and co-benefits to multiple recipients, as well as a local demonstration project in Central Kalimantan Province. These REDD+ incentives are often conflated with the neoliberalisation of the climate agenda, focused on the adoption of market instruments and the commodification of forest carbon. However, REDD+ incentives in Indonesia include diverse policy mechanisms and encompass multiple objectives – such as the delivery of social services and employment schemes aimed at improving community livelihoods. These incentives employ a welfare environmentality, where government agencies and their partners deliver certain rights and socio-economic security for communities in return for adopting practices that improve carbon and forest management. The application of welfare environmentality shows how incentive frameworks operate as a state intervention designed to restructure relations between people and environmental resources.  相似文献   
197.
Mercury (Hg) in fish can present a potential risk to wildlife and human consumers. Mercury levels were determined in 12 fish species and 2 invertebrate species from the French coast of the Eastern English Channel collected in June and November 2012. Total mercury concentrations in the muscle tissues ranged between 0.04 and 1.63 µg g-1 (d.w.). Dab and sandeel displayed a significant positive correlation between Hg concentrations and fish length. Seasonal differences in Hg concentrations were observed for dab and shrimp. The lesser weever showed significantly higher concentrations of Hg (0.97 ± 0.34 µg g-1 d. w.) than all other species. Gobies and sprat, which had the smallest size, showed significantly lower concentrations than herring, whiting, pout and sardine. Among the considered species, flatfish such as dab, flounder, plaice and sole displayed intermediate levels of Hg. In the present study, the fish age expressed as specimen length seems to be one of the major factors governing Hg contents in muscle tissues. Finally, mercury concentrations in commercial fish from the Eastern English Channel were below the levels fixed by the European Union for total mercury in edible parts of fish products.  相似文献   
198.
Prediction of phosphorus (P) availability from soil-applied composts and manure is important for agronomic and environmental reasons. This study utilized chemical properties of eight composted and two non-composted beef cattle (Bos taurus) manures to predict cumulative phosphorus uptake (CPU) during a 363-d controlled environment chamber bioassay. Ten growth cycles of canola (Brassica napus L.) were raised in pots containing 2 kg of a Dark Brown Chernozemic clay loam soil (fine-loamy, mixed, Typic Haploboroll) mixed with 0.04 kg of the amendments. Inorganic P fertilizer (KH2PO4) and an unamended control were included for comparison. All treatments received a nutrient solution containing an adequate supply of all essential nutrients, except P, which was supplied by the amendments. Cumulative P uptake was similar for composted (74 mg kg-1 soil) and non-composted manures (60 mg kg-1 soil) and for the latter and the fertilizer (40 mg kg-1 soil). However, the CPU was significantly higher for organic amendments than the control (24 mg kg-1 soil) and for composted manure than the fertilizer. Apparent phosphorus recovery (APR) from composted manure (24%) was significantly lower than that from non-composted manure (33%), but there was no significant difference in APR between the organic amendments and the fertilizer (27%). Partial least squares (PLS) regression indicated that only two parameters [total water-extractable phosphorus (TPH2O) and total phosphorus (TP) concentration of amendments] were adequate to model amendment-derived cumulative phosphorus uptake (ACPU), explaining 81% of the variation in ACPU. These results suggest that P availability from soil-applied composted and non-composted manures can be adequately predicted from a few simple amendment chemical measurements. Accurate prediction of P availability and plant P recovery may help tailor manure and compost applications to plant needs and minimize the buildup of bioavailable P, which can contribute to eutrophication of sensitive aquatic systems.  相似文献   
199.
A probabilistic Bayesian method called weights of evidence (WofE) was used to develop a synthetic dataset of cattle farm locations at a national scale across Australia. The synthetic dataset was required for the modelling of livestock movements with a view to assessing biosecurity implications. The WofE method is based on the analysis of spatial relationships between evidential patterns with respect to an event, such as the actual location of a farm. The evidential patterns of cattle farms were derived from maps of land use, land tenure, drainage systems, roads, settlements and long-term averaged rainfall. These evidential patterns were used for delineating and ranking land areas suitable for cattle farming. For each evidential pattern statistics such as a positive weight, a negative weight and a contrast were calculated for estimating the degree of correlation between the evidential patterns and known farm locations. The integrated evidential patterns of known farms were then used for estimating posterior probabilities and splitting land into five different classes according to its suitability for farming.
I. V. EmelyanovaEmail:
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200.
The potential for using plant pathogens and seeds as indicator organisms for assessing sanitization of plant wastes during composting was tested in bench-scale flask and large-scale systems. Plasmodiophora brassicae was unsuitable due to high temperature tolerance in dry to moist composts, and detection of viable inoculum post-composting using bioassay plants not corresponding with that using TaqMan® PCR, possibly due to preservation of nucleic acids at elevated temperatures. Several other plant pathogens (Sclerotinia sclerotiorum, Microdochium nivale, Phytophthora cinnamomi and Phytophthora nicotianae) were unsuitable due their low temperature tolerance. Fusarium oxysporum f.sp. cepae and f.sp. radicis-lycopersici chlamydospores and tomato seeds were suitable indicators due to their moderate temperature tolerance and ease of viability testing post-composting. Abutilon seeds were more tolerant than tomato seeds of compost temperatures ?52 °C but more prone to degradation at lower temperatures and therefore less suitable as indicators. Relationships between compost temperature during exposures of 2-10 days and subsequent viability of the above chlamydospores or seeds enabled the sanitizing effect of composting processes to be predicted within 2-6 days. Plant waste type (woody or vegetable) had a small but significant effect on the relationship for tomato seeds but not for F. oxysporum chlamydospores.  相似文献   
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