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Recruitment of juvenile red drum in North Carolina: Spatiotemporal patterns of year-class strength and validation of a seine survey

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NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT 2008年第4期28卷 1086-1098页

作者： Bacheler, Nathan M. Paramore, Lee M. Buckel, Jeffrey A. Scharf, Frederick S. N Carolina State Univ Dept Zool Ctr Marine Sci & Technol Morehead City NC 28557 USA N Carolina Div Marine Fisheries Wanchese NC 27981 USA Univ N Carolina Dept Biol & Marine Biol Wilmington NC 28403 USA

Sixteen years of data from a North Carolina Division of Marine Fisheries seining survey were analyzed to assess the validity of the survey, describe spatial and temporal patterns in recruitment of red drum Sciaenops ocellatus, and evaluate factors that potentially contribute to recruitment variation. Overall, 11,817 age-0 red drum (total length 11-104 mm) were collected in the survey during 1991-2006. Annual estimates of red drum recruitment were variable over time and showed no long-term trend. The dome-shaped catch-per-unit-effort (CPUE) pattern of all annual cohorts indicated that the seine survey captured peak abundance levels each year;the spatial coverage of the survey also appeared to be adequate. Regional correlations within North Carolina were strongest for areas that were adjacent to one another, and the North Carolina statewide index was not Correlated with indices from Florida or Texas, suggesting that factors controlling recruitment of red drum operate at a scale of tens to hundreds of kilometers. Age-0 red drum were caught at temperatures ranging from 8.5 degrees C to 33.5 degrees C and at salinities from 0.0 to 34.7 practical salinity units (psu;1 psu approximate to 1 parts per thousand). A generalized additive model explained only 8.1% of the variation in age-0 abundance, suggesting that early juvenile abundance cannot be predicted with these abiotic factors. Variation in loss rates of age-0 red drum appeared to be independent of variation in cohort density. The CPUE of age-0 red drum was correlated with harvest of age-2 fish 2 years later, suggesting that additional modification of year-class strength after the early juvenile stage is moderate or weak. Results of this study have improved our understanding of red drum recruitment patterns while simultaneously validating the seine survey.

关键词： year-class strength spatiotemporal pattern recruitment variation spatial coverage peak abundance practical salinity unit regional correlation cohort density

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Evaluation of a UHF radar surface current mapping system in an intertidal salt marsh

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JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY 2007年第12期24卷 2120-2127页

作者： Styles, Richard Teague, Calvin C. Univ S Carolina Dept Geol Sci Marine Sci Program Columbia SC 29208 USA CODAR Ocean Sensors Ltd Mountain View CA USA

A UHF RiverSonde radar system was deployed in an intertidal salt marsh during November and December 2005 near Georgetown, South Carolina. The purpose of this experiment was to evaluate radar performance in a coastal plain salt marsh, where the channels are highly sinuous and the flow is dominated by tides. To help evaluate radar performance, an acoustic current profiler was placed in a large subtidal channel located in the field of view of the radar. Comparisons indicated that the radar accurately reproduced both the magnitude and phasing of the surface current. spatial coverage was generally good in the channels but much more sporadic over the marsh platform. Temporal coverage in the channel was also good and correlated with wind speed. Reliable measurements were obtained under wind speeds as low as 2-3 m s(-1), which are common at this site. In addition, some unexpected signals were seen at near zero Doppler shift, which were attributed to the saltwater vegetation Spartina alterniflora, which acted as effective radar targets. However, these signals were uncorrelated and likely can be filtered.

关键词： .Speeds UHF RiverSonde spatial coverage marsh platform

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Optimal neural connection mechanism in cortical network

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BMC Neuroscience 2008年第1期9卷 1-1页

作者： Qingbai Zhao Yi-Yuan Tang Institute of Neuroinformatics and Laboratory for Brain and Mind Dalian University of Technology Dalian 116024 China Department of Psychology University of Oregon Eugene OR 97403 USA

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Geographic and taxonomic bias in land snail distribution data of Hungary

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COMMUNITY ECOLOGY 2007年第2期8卷 239-246页

作者： Solymos, P. Szent Istvan Univ Fac Vet Sci Dept Ecol H-1077 Budapest Hungary

The importance of accurate species databases is debated in the recent literature of biodiversity assessment, considering that limited resources for conservation could be better allocated to assessment based on cost effective biodiversity features. I aimed to provide an understanding of sampling bias and provide practical advice to minimize bias either before or after data collection. I used 10x10 km(2) UTM grid data for 121 land snail species to account for geographic and taxonomic sampling bias in Hungary. Sampling intensity corrected for species richness varied significantly among regions, although regions were not good predictors of sampling intensity. Residuals were significantly autocorrelated in 15 km distance, indicating small scale heterogeneity in sampling intensity compared to species richness. Sampling coverage and intensity were higher close to human settlements and sampling intensity was higher within protected areas than outside. Commonness of species was positively associated with sampling intensity, while some rare species were over-represented in the records. Sampling intensity of microsnails (<3 mm) was significantly lower than that of the more detectable large species (> 15 mm). Systematic effects of the collecting methods used in malacological research may be responsible for these differences. Understanding causes of sampling bias may help to reduce its effects in ecological, biogeographical and conservation biological applications, and help to guide future research.

关键词： biodiversity biotic impediment Gastropoda Mollusca protected areas spatial autocorrelation spatial coverage spatial intensity

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Air monitoring of persistent organic pollutants in the Great Lakes: IADN vs. AEOLOS

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ENVIRONMENTAL MONITORING AND ASSESSMENT 2005年第1-3期100卷 201-216页

作者： Simcik, MF Univ Minnesota Sch Publ Hlth Div Environm & Occupat Hlth Minneapolis MN 55455 USA

When designing a monitoring campaign, one has to consider many factors in the decision to perform a long-term synoptic monitoring program or a short-term intensive study. Each has its own advantages and disadvantages. This paper compares and contrasts the information obtained from two studies conducted on the Laurentian Great Lakes. One, the Integrated Atmospheric Deposition Network (IADN), is a long-term synoptic monitoring study and the other, the Atmospheric Exchange Over Lakes and Oceans (AEOLOS), was a short-term intensive study. The advantages of long-term synoptic monitoring programs are providing greater spatial information, the relative influence of long and short-range transport on the regional background, gross loadings representative of the majority of each lake and long-term temporal trends. Short-term intensive studies provide more information on the processes governing sources, transport and deposition, such as the urban/industrial influence on adjacent large water bodies, specific sources to an urban/industrial area and short-term fluctuations in concentrations due to meteorology, source strength and photochemical reactions. Using information provided by both the IADN and AEOLOS studies, areas of urban influence are predicted for each of the five Great Lakes.

关键词： atmospheric loadings POPs source apportionment spatial coverage temporal trends

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spatial competitive interaction of retail store formats:: modeling proposal and empirical results

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JOURNAL OF BUSINESS RESEARCH 2005年第4期58卷 457-466页

作者： González-Benito, S Univ Salamanca Fac Econ & Empresa Dpto Adm & Econ Empresa Salamanca 37007 Spain

This study builds on the spatial competitive interaction of store formats that are often considered generic retail positioning profiles. Specifically, a modeling proposal is developed that focuses on the role of the spatial coverage reached by particular store formats as a determining factor of intraurban market response. The proposal is assessed through an application to the Spanish retail context that tries to identify competitive frictions among the supermarket, the hypermarket, and the discount store. The results demonstrate the explanatory capabilities of the model and reveal interesting conclusions related to the impact of spatial growth by store formats on food shopping patterns. There is more intense competition between the discount store and the hypermarket, and the classic supermarket form maintains a balanced rivalry with both. The development of larger discount stores seems to affect the supermarket market share more severely, whereas the development of discount stores that offer parking subtracts more demand from the hypermarket. (c) 2003 Elsevier Inc. All rights reserved.

关键词： store format competitive interaction spatial coverage market share

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S-wave velocity tomography: Small-scale laboratory application

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GEOTECHNICAL TESTING JOURNAL 2005年第4期28卷 336-344页

作者： Lee, JS Fernandez, AL Santamarina, JC Korea Univ Seoul 136701 South Korea Georgia Inst Technol Atlanta GA 30332 USA AH Beck Fdn Co San Antonio TX 78216 USA

Arrays of bender elements are combined with simple. yet robust inversion algorithms to develop a device for S-wave tomography. A fixed frame configuration complemented with a new versatile bender element installation permits reducing measurement errors, System design involves optimal selection of transducer separation, a frame design that prevents wave transmission, and an adequate calibration procedure. Reliable tomographic images are obtained by combining data preprocessing and the regularized least squares solution, Given the small size of the data sets, inversion techniques based on a parametric representation of the medium are implemented as well, The tomographic system is tested at low confinement and within a true triaxial cell. Results show the potential of tomographic imaging in the characterization of geotechnical systems and in the monitoring of subsurface processes. In particular, shear wave velocity tomography permits monitoring changes in the velocity field, which is related to the average effective stress in freshly-remolded uncemented soils. A minimum anomaly size and velocity contrast art! required for detection. Diffraction healing hinders the detection of low velocity anomalies.

关键词： diffraction healing inversion least squares regularization parametric representation pixel representation spatial coverage tunnels

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Recent anomalies in Great Lakes ice cover based on statistical analysis and observation

Recent anomalies in Great Lakes ice cover based on statistic...

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IEEE International Geoscience and Remote Sensing Symposium

作者： Leshkevich, GA Nghiem, SV NOAA Great Lakes Environm Res Lab Ann Arbor MI 48105 USA

ISBN: (纸本)0780387422

In this work, the anomalous change in ice cover on the Great Lakes was observed and recorded during our GLAWEX1997, GLAWAEX2002 and GLAWEX2003 field experiments on the upper Great Lakes. The objective of the experiments is to develop algorithms to map and classify ice using satellite synthetic aperture radar (SAR) and scatterometer data. Moreover, the large spatial and high temporal coverage of satellite scatterometer measurements with its all-weather, day/night sensing capabilities make it well suited to map and monitor Great Lakes ice cover to extend the historical climatological record that was largely developed using aircraft observations.

关键词： ice synthetic aperture radar statistical analysis remote sensing by radar meteorology climatology lakes GLAWEX1997 field experiment GLAWAEX2002 field experiment GLAWEX2003 field experiment Great Lakes ice cover satellite synthetic aperture radar SAR spatial coverage temporal coverage satellite scatterometer measurement weather sensing capability climatological record aircraft observation Synthetic aperture radar Aircraft detection Statistical analysis Statistical methods temporal coverage Radar remote sensing Ice Cover Climatology Ice Meteorology Great Lakes Data analysis lakes

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Statistical visualization for data exploration: a case study on Sydney Olympic Park

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CHEMOSPHERE 2003年第9期52卷 1601-1614页

作者： Shao, Q Li, Y Campbell, E De Boer, ES Laginestra, E Statzenko, A CSIRO Math & Informat Sci Leewin Ctr Floreat Pk WA 6014 Australia Sydney Olympic Pk Author Silverwater NSW 2128 Australia

Due to the powerful graphic interface in modern computers, visualization techniques have become more and more popular for data exploration. As a preliminary investigation, visualization is a greatly useful tool to lead to further statistical analysis and modelling. It is likely that historical environmental data from a range of different studies may contain useful information that should be assessed for determining management actions. However, these historical data are collected from many different studies, which have different space and/or time scales making the visualization process complicated. In this paper we present several ways of visualizing historical data based on a study at Sydney Olympic Park. The tools include spatial coverage and variation for different spatial resolutions, temporal coverage and time series plots for different time scales, multi-panel scatterplots for a small number of variables and "one-to-all" scatterplots for a large number of variables. Crown Copyright (C) 2003 Published by Elsevier Ltd. All rights reserved.

关键词： multi-panel scatterplot one-to-all scatterplot spatial coverage spatial variation Sydney Olympic Park temporal coverage temporal variation

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Accessibility tradeoffs in public transit planning

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Journal of Geographical Systems 2003年第1期5卷 93-107页

作者： Murray, Alan T. Wu, Xiaolan Department of Geography The Ohio State University Columbus OH 43210 1036 Derby Hall United States

spatial accessibility is a critical consideration in the provision of services, both public and private. In public transit planning, accessibility is comprised of access and geographic coverage. Interestingly, these two considerations are somewhat at odds with each other. Access is important because it is the process associated with getting to and departing from the service. Such access is typically perceived of in spatial terms as the physical proximity to transit stops or stations. Additional stops along a route usually mean greater access, because a stop is more likely to be within an acceptable walking/driving standard for a larger number of people. On the other hand, more stops and greater access slow transit travel speeds, thereby decreasing the area of service reachable given a travel time budget. More stops along a route translate to greater service interruption and longer travel times. The faster the travel time, the more desirable the service. Further, if travel times become excessive, then user demand for service will decrease. All of this means that stop spacing along a route is central to accessibility, as it is a tradeoff of access (more stops) and geographic coverage (service efficiency through less stops). This paper details modeling approaches for addressing accessibility concerns in an integrated fashion. Bus-based transit service in Columbus, Ohio will be utilized to illustrate the usefulness of these approaches in transit planning.

关键词： Access Location-allocation models spatial coverage Transportation

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