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61.
Gary S. Johnson Bryce A. Contor Donna M. Cosgrove 《Journal of the American Water Resources Association》2008,44(1):27-36
Abstract: Water right transfers are one of the basic means of implementing changes in water use in the highly appropriated water resource systems of the western United States. Many of these systems are governed by the Prior Appropriation Doctrine, which was not originally intended for application to ground‐water pumping and the conjunctive management of ground water and surface water, and thus creates an administrative challenge. That challenge results from the fact that ground‐water pumping can affect all interconnected surface‐water bodies and the effects may be immeasurably small relative to surface water discharge and greatly attenuated in time. Although we may have the ability to calculate the effects of ground‐water pumping and transfers of pumping location on surface‐water bodies, mitigating for all the impacts of each individual transfer is sufficiently inefficient that it impedes the transfer process, frustrates water users, and consequently inhibits economic development. A more holistic approach to ground‐water right transfers, such as a ground‐water accounting or banking scheme, may adequately control transfer third‐party effects while reducing mitigation requirements on individual transfers. Acceptance of an accounting scheme can accelerate the transfer process, and possibly reduce the administrative burden. 相似文献
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Summary. Workers of the amblyoponine species Mystrium rogeri employ trail communication during recruitment to food sources and new nest sites. The trail pheromone originates from a hitherto
unknown sternal gland located in the 7th abdominal sternite. The recruiting ant deposits the gland secretions by a special
gaster-dragging behavior. The recruitment behavior can be complemented by a rapid vertical body shaking performed by some
recruiting ants inside the nest. M. rogeri workers possess a large pygidial gland, the secretion of which elicits a repellent response in other ant species.
Received 25 May 1998; accepted 15 June 1998. 相似文献
64.
Burr G Hume M Ricke S Nisbet D Gatlin D 《Journal of environmental science and health. Part. B》2008,43(3):253-260
This study examined the effects of brewers yeast, fructooligosaccharide (FOS), and GroBiotic-A, a mixture of partially autolyzed brewers yeast, dairy components and dried fermentation products, on the intestinal microbial community of red drum, Sciaenops ocellatus. Gastrointestinal (GI) tracts were aseptically removed from three sub-adult red drum previously maintained on a commercial diet and placed in an anaerobic chamber. Intestinal contents were removed, diluted and incubated in vitro in one of four liquid media: normal diet alone, diet + 2% (w/w) GroBiotic-A, diet + 2% brewers yeast, and diet + 2% FOS. After 24 and 48 h of incubation at 25 degrees C, supernatants were removed for volatile fatty acid (VFA) analysis and DNA was extracted for denaturing gradient gel electrophoresis (DGGE) analysis. Polymerase chain reaction (PCR) was performed on a highly conserved region of M 16S rDNA and the amplicons were subjected to DGGE. The microbial community (MC) fingerprint was used to distinguish microbial populations. The intestinal contents incubated with GroBiotic-A had significantly (P<0.05) higher acetate and total VFA concentrations at 48 h compared to the other treatments. DGGE analysis demonstrated that the microbial community was significantly altered by Grobiotic-A and brewers yeast. 相似文献
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Finola E. Cliffe Gary Walsh Thomas F. O'Dwyer 《Journal of Cleaner Production》2010,18(10-11):1066-1072
Human gene therapy is currently seeing an increase in the use of plasmid (pDNA)-based vectors as a preferred choice of vehicle for delivery of the therapeutic gene into the body. In this regard, the environmental impacts of the waste streams from the possible industrial scale manufacture of pDNA require more detailed assessment. In this study, an initial assessment was made of the nutrient phosphorus (P) inputs to four fermentation processes recommended for the industrial scale production of pDNA for the purposes of gene therapy. Phosphorus inputs to each of the four selected fermentation processes ranged from approximately 60 mg l?1 up to 3000 mg l?1 in the fresh media. However, the spent media waste from each of the processes exhibited only a minor reduction in the phosphorus concentrations indicating minimal uptake of P by the microorganisms. This unutilised excess level of phosphorus nutrient within the waste streams poses a strong potential for environmental impact. Waste minimisation studies were undertaken on one model fermentation process with the aim of reducing unnecessary phosphorus input. An optimised media containing a 98% reduction in added P to the media was developed. This phosphorus-minimised media had little quantitative effect upon cell biomass produced and no effect upon the quantity or quality of pDNA produced, relative to the control media. The reduction in P requirement results in an overall cost savings of 12% per fermentation batch, would simplify subsequent wastewater treatment and would contribute to slowing the depletion rate of a valuable, finite natural resource. 相似文献
67.
Robert A. Rose Dirck Byler J. Ron Eastman Erica Fleishman Gary Geller Scott Goetz Liane Guild Healy Hamilton Matt Hansen Rachel Headley Jennifer Hewson Ned Horning Beth A. Kaplin Nadine Laporte Allison Leidner Peter Leimgruber Jeffrey Morisette John Musinsky Lilian Pintea Ana Prados Volker C. Radeloff Mary Rowen Sassan Saatchi Steve Schill Karyn Tabor Woody Turner Anthony Vodacek James Vogelmann Martin Wegmann David Wilkie Cara Wilson 《Conservation biology》2015,29(2):350-359
In an effort to increase conservation effectiveness through the use of Earth observation technologies, a group of remote sensing scientists affiliated with government and academic institutions and conservation organizations identified 10 questions in conservation for which the potential to be answered would be greatly increased by use of remotely sensed data and analyses of those data. Our goals were to increase conservation practitioners’ use of remote sensing to support their work, increase collaboration between the conservation science and remote sensing communities, identify and develop new and innovative uses of remote sensing for advancing conservation science, provide guidance to space agencies on how future satellite missions can support conservation science, and generate support from the public and private sector in the use of remote sensing data to address the 10 conservation questions. We identified a broad initial list of questions on the basis of an email chain‐referral survey. We then used a workshop‐based iterative and collaborative approach to whittle the list down to these final questions (which represent 10 major themes in conservation): How can global Earth observation data be used to model species distributions and abundances? How can remote sensing improve the understanding of animal movements? How can remotely sensed ecosystem variables be used to understand, monitor, and predict ecosystem response and resilience to multiple stressors? How can remote sensing be used to monitor the effects of climate on ecosystems? How can near real‐time ecosystem monitoring catalyze threat reduction, governance and regulation compliance, and resource management decisions? How can remote sensing inform configuration of protected area networks at spatial extents relevant to populations of target species and ecosystem services? How can remote sensing‐derived products be used to value and monitor changes in ecosystem services? How can remote sensing be used to monitor and evaluate the effectiveness of conservation efforts? How does the expansion and intensification of agriculture and aquaculture alter ecosystems and the services they provide? How can remote sensing be used to determine the degree to which ecosystems are being disturbed or degraded and the effects of these changes on species and ecosystem functions? 相似文献
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Jae H. Ryu Bryce Contor Gary Johnson Richard Allen John Tracy 《Journal of the American Water Resources Association》2012,48(6):1204-1220
Abstract: Water supply uncertainty continues to threaten the reliability of regional water resources in the western United States. Climate variability and water dispute potentials induce water managers to develop proactive adaptive management strategies to mitigate future hydroclimate impacts. The Eastern Snake Plain Aquifer in the state of Idaho is also facing these challenges in the sense that population growth and economic development strongly depend on reliable water resources from underground storage. Drought and subsequent water conflict often drive scientific research and political agendas because water resources availability and aquifer management for a sustainable rural economy are of great interest. In this study, a system dynamics approach is applied to address dynamically complex problems with management of the aquifer and associated surface‐water and groundwater interactions. Recharge and discharge dynamics within the aquifer system are coded in an environmental modeling framework to identify long‐term behavior of aquifer responses to uncertain future hydrological variability. The research shows that the system dynamics approach is a promising modeling tool to develop sustainable water resources planning and management in a collaborative decision‐making framework and also to provide useful insights and alternative opportunities for operational management, policy support, and participatory strategic planning to mitigate future hydroclimate impacts in human dimensions. 相似文献