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261.
Leptocephali of the tropical eel Anguilla marmorata have been consistently collected in the same area of the North Equatorial Current (NEC) in the western North Pacific during three consecutive cruises in June and July of 1991 (N=28) and 1994 (N=20), and July and September of 1995 (N=27), indicating that this is a spawning area of this species. These leptocephali were collected from 130°E to 142°E and 12°N to 20°N, to the west of the Mariana Islands, in 20 tows in 1991, in 13 tows in 1994 and in 17 tows in 1995, indicating a widespread presence, but a relatively low abundance. Six of these specimens (16.3-36.0 mm total length) from the 1995 cruise, which were of the typical size range of these leptocephali, were genetically confirmed to be A. marmorata in a previous study. The consistent presence of recently spawned A. marmorata leptocephali (9-20 mm) in all 3 years, suggests that the western region of the NEC is the spawning area of the northern population of A. marmorata that was identified in a recent population genetics study. These leptocephali would thus be transported westward by the NEC and then transported north into the Kuroshio Current and toward Taiwan and Japan, or south toward the southern Philippines and into the Celebes Sea by the Mindanao Current. Available evidence indicates that A. marmorata may have potentially year-round spawning, and the presence of a spawning area of this species in the same region as that of Anguilla japonica suggests that the northern population of A. marmorata has evolved a spawning migration from East Asia, the Philippines and the Celebes Sea region to the NEC area, but differs from A. japonica by having some individuals that recruit to more southern areas. 相似文献
262.
Ryan C. Miller D. Phillip Guertin Philip Heilman 《Journal of the American Water Resources Association》2004,40(2):347-357
ABSTRACT: Watershed management decision making is a complex process. Cooperation and communication among federal, state, and local stakeholders is required while balancing biophysical and socioeconomic concerns. The public is taking part in environmental decisions, and the need for technology transfer from public agencies to stakeholders is increasing. Information technology has had a profound influence on watershed management over the past decade. Advances in data acquisition through remote sensing, data utilization through geographic information systems (GIS), and data sharing through the Internet have provided watershed managers access to more information for management decisions. In the future, applications incorporating hydrologic simulation models, GIS, and decision support systems will be deployed through the Internet. In addition to challenges in making complex modeling technology available to diverse audiences, new information technology issues, such as interoperability, Internet access, and security, are introduced when GIS, simulation models, and decision support systems are integrated in an Internet environment. This paper presents a review of current use of information technology in watershed management decision making and a discussion of issues created when developing Internet based, integrated watershed management decision support systems. A prototype spatial decision support system (SDSS) for rangeland watershed management was developed using web services, which are components that communicate using text based messages, thus eliminating proprietary protocols. This new framework provides an extensible, accessible, and interoperable approach for SDSS. 相似文献
263.
Vedal S Hannigan MP Dutton SJ Miller SL Milford JB Rabinovitch N Kim SY Sheppard L 《Atmospheric environment (Oxford, England : 1994)》2009,43(9):1666-1673
Improved understanding of the sources of air pollution that are most harmful could aid in developing more effective measures for protecting human health. The Denver Aerosol Sources and Health (DASH) study was designed to identify the sources of ambient fine particulate matter (PM(2.5)) that are most responsible for the adverse health effects of short-term exposure to PM (2.5). Daily 24-hour PM(2.5) sampling began in July 2002 at a residential monitoring site in Denver, Colorado, using both Teflon and quartz filter samplers. Sampling is planned to continue through 2008. Chemical speciation is being carried out for mass, inorganic ionic compounds (sulfate, nitrate and ammonium), and carbonaceous components, including elemental carbon, organic carbon, temperature-resolved organic carbon fractions and a large array of organic compounds. In addition, water soluble metals were measured daily for 12 months in 2003. A receptor-based source apportionment approach utilizing positive matrix factorization (PMF) will be used to identify PM (2.5) source contributions for each 24-hour period. Based on a preliminary assessment using synthetic data, the proposed source apportionment should be able to identify many important sources on a daily basis, including secondary ammonium nitrate and ammonium sulfate, diesel vehicle exhaust, road dust, wood combustion and vegetative debris. Meat cooking, gasoline vehicle exhaust and natural gas combustion were more challenging for PMF to accurately identify due to high detection limits for certain organic molecular marker compounds. Measurements of these compounds are being improved and supplemented with additional organic molecular marker compounds. The health study will investigate associations between daily source contributions and an array of health endpoints, including daily mortality and hospitalizations and measures of asthma control in asthmatic children. Findings from the DASH study, in addition to being of interest to policymakers, by identifying harmful PM(2.5) sources may provide insights into mechanisms of PM effect. 相似文献
264.
John A. Robertson Alex W. Thomas Julien Modolo Jodi Miller Nicole Juen Alexandre Legros Frank S. Prato 《The Environmentalist》2011,31(2):134-139
The field of bioelectromagnetics, consisting of the study of the interaction between electromagnetic fields and biological
systems, has been rapidly expanding in the recent years. One important factor that contributes importantly to the development
of this field is the continuing advances in technology allowing researchers to investigate different endpoints, or to more
precisely measure changes, if any. Hybrid functional imaging is a rapidly maturing field that opens new, important horizons
for bioelectromagnetics research. Indeed, unraveling the interaction mechanisms of electromagnetic fields on biological systems
(with an emphasis on the brain) requires a monitoring of electrical, functional, and metabolic activity of living tissue at
different temporal and spatial scales. Individual tools (e.g., electroencephalography, EEG; functional magnetic resonance
imaging, fMRI) are limited in their ability to detect the effects of electromagnetic interaction at specific temporal and
spatial scales, so combining these imaging methods offers a unique opportunity to provide a more comprehensive view of effects
in living tissue. In this paper, we will present the different imaging techniques that are available to bioelectromagnetics
researchers, including their capabilities and how they are complemented by simultaneous hybrid imaging. Future possibilities
of hybrid imaging technologies are discussed. 相似文献
265.
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267.
Christine E. Wilkinson Alex McInturff Jennifer R. B. Miller Veronica Yovovich Kaitlyn M. Gaynor Kendall Calhoun Harshad Karandikar Jeff Vance Martin Phoebe Parker-Shames Avery Shawler Amy Van Scoyoc Justin S. Brashares 《Conservation biology》2020,34(4):854-867
Carnivore predation on livestock is a complex management and policy challenge, yet it is also intrinsically an ecological interaction between predators and prey. Human–wildlife interactions occur in socioecological systems in which human and environmental processes are closely linked. However, underlying human–wildlife conflict and key to unpacking its complexity are concrete and identifiable ecological mechanisms that lead to predation events. To better understand how ecological theory accords with interactions between wild predators and domestic prey, we developed a framework to describe ecological drivers of predation on livestock. We based this framework on foundational ecological theory and current research on interactions between predators and domestic prey. We used this framework to examine ecological mechanisms (e.g., density-mediated effects, behaviorally mediated effects, and optimal foraging theory) through which specific management interventions operate, and we analyzed the ecological determinants of failure and success of management interventions in 3 case studies: snow leopards (Panthera uncia), wolves (Canis lupus), and cougars (Puma concolor). The varied, context-dependent successes and failures of the management interventions in these case studies demonstrated the utility of using an ecological framework to ground research and management of carnivore–livestock conflict. Mitigation of human–wildlife conflict appears to require an understanding of how fundamental ecological theories work within domestic predator–prey systems. 相似文献
268.
269.
E. Garcia-Anton S. Cuezva V. Jurado E. Porca A. Z. Miller A. Fernandez-Cortes C. Saiz-Jimenez S. Sanchez-Moral 《Environmental science and pollution research international》2014,21(1):473-484
Altamira Cave (north of Spain) contains one of the world's most prominent Paleolithic rock art paintings, which are threatened by a massive microbial colonization of ceiling and walls. Previous studies revealed that exchange rates between the cave and the external atmosphere through the entrance door play a decisive role in the entry and transport of microorganisms (bacteria and fungi) and nutrients to the interior of the cave. A spatial-distributed sampling and measurement of carrier (CO2) and trace (CH4) gases and isotopic signal of CO2 (δ13C) inside the cave supports the existence of a second connection (active gas exchange processes) with the external atmosphere at or near the Well Hall, the innermost and deepest area of the cave. A parallel aerobiological study also showed that, in addition to the entrance door, there is another connection with the external atmosphere, which favors the transport and increases microorganism concentrations in the Well Hall. This double approach provides a more complete knowledge on cave ventilation and revealed the existence of unknown passageways in the cave, a fact that should be taken into account in future cave management. 相似文献
270.
Nucleotide sequences have been determined for 31 homologous 118 base-pair highly repeated DNA sequences from seven species ofAcropora. A matrix was constructed from the sequence data and subjected to phylogenetic analysis using heuristic search routines in the PAUP (phylogenetic analysis using parsimony) program, Version 3.0L. These analyses confirm a close relationship between two species of one subgeneric group (A. pulchra andA. millepora), but identify a division in a group of six species which is contrary to taxonomic groupings based on morphological criteria. 相似文献