Relationships Between Ground-Water Silica, Total Dissolved Solids, and Specific Electrical Conductivity

Specific electrical conductivity (SEC), total dissolved solids (TDS), and silica (SiO₂) are ground-water quality parameters routinely measured in a laboratory. Electrical conductivity measurements are made quickly and are less costly than TDS measurements. Once the relationship between the parameters is determined by regression analysis, TDS can be estimated quickly from the SEC and SiO₂ measurements. Water quality data from 25 city wells in Fresno, California, and historical ground-water quality data from the adjacent San Joaquin River/Kings River alluvial interfan (central San Joaquin Valley, California), the Kaweah River alluvial fan, and the Kern River alluvial fan (southern San Joaquin Valley) were used in this investigation. For the specific hydrologic areas studied, the model's TDS predictive ability is improved when SiO₂ is included with SEC as the independent variables.     

The Clouds of the Middle Troposphere: Composition, Radiative Impact, and Global Distribution

The clouds of the middle troposphere span the temperature range where both ice and liquid water in a supercooled state can exist. However, because one phase tends to dominate, of the two midlevel cloud types, altostratus are deep ice-dominated, while altocumulus are shallow water-dominated, mixed-phase clouds with ice crystal virga typically trailing below. Multiple remote sensor examples of these cloud types are given to illustrate their main features, and the radiative consequences of the different cloud microphysical compositions are discussed. Spaceborne radar and lidar measurements using the CloudSat and CALIPSO satellites are analyzed to determine the global distributions of cloud frequencies and heights of these clouds. It is found that together these little-studied clouds cover ~25% of the Earth’s surface, which is about one-third of the total cloud cover, and thus represent a significant contribution to the planet’s energy balance.     

An In Situ Multilevel Sampler for Preventive Monitoring and Study of Hydrochemical Profiles in Aquifers

Abstract
A modular multilevel sampler was developed and utilized for sampling undisturbed ground water chemical profiles and gases in both the saturated and the unsaturated zone. Sampling at 3cm depth intervals is based on the dialysis-cell method and has no depth limitations. The sampler may be used for the development of early warning monitoring systems and research.     

An Automatic Method of Direct Interpretation of Residual Gravity Anomaly Profiles due to Spheres and Cylinders

We have developed a least-squares minimization approach to determine the depth and the amplitude coefficient of a buried structure from residual gravity anomaly profile. This approach is basically based on application of Werner deconvolution method to gravity formulas due to spheres and cylinders, and solving a set of algebraic linear equations to estimate the two-model parameters. The validity of this new method is demonstrated through studying and analyzing two synthetic gravity anomalies, using simulated data generated from a known model with different random error components and a known statistical distribution. After being theoretically proven, this approach was applied on two real field gravity anomalies from Cuba and Sweden. The agreement between the results obtained by the proposed method and those obtained by other interpretation methods is good and comparable. Moreover, the depth obtained by the proposed approach is found to be in very good agreement with that obtained from drilling information.     

Relationships between Atmospheric Precipitation,Evaporation, Temperature,and Production of Aquatic Ecosystems

The average production capacity of aquatic ecosystems is shown to be proportional to the coefficient of variations of substance concentrations in atmospheric precipitation and the sum of effective temperatures. The values of ichthyomass and primary production of phytoplankton per 1°C of the sum of effective temperatures multiplied by the coefficient of variations of substance concentration in atmospheric precipitation are proposed as ecological thermometers to be used in water bodies in different geographic zones of Europe and North America.     

Discrimination Between Nuclear Explosions and Earthquakes: An Application of Wigner Distribution

In this paper,the nonstationary theory of Wigner Distribution is used to discriminate between underground nuclear explosions and natural earthquakes.Five underground explosions in Kazakhstan region and seven regional earthquakes in its adjacent areas have been analyzed.The result shows that the transient spectra of underground nuclear explosions are concentrated in the frequency range of 5-10 Hz,while the transient spectra of natural earthquakes are distributed widely from lower frequency to higher frequency.The transient frequency of nuclear explosions shows linearity in the first stage(0相似文献   

Uncertainty Estimate of Surface Irradiances Computed with MODIS-, CALIPSO-, and CloudSat-Derived Cloud and Aerosol Properties

Differences of modeled surface upward and downward longwave and shortwave irradiances are calculated using modeled irradiance computed with active sensor-derived and passive sensor-derived cloud and aerosol properties. The irradiance differences are calculated for various temporal and spatial scales, monthly gridded, monthly zonal, monthly global, and annual global. Using the irradiance differences, the uncertainty of surface irradiances is estimated. The uncertainty (1σ) of the annual global surface downward longwave and shortwave is, respectively, 7?W?m^?2 (out of 345?W?m^?2) and 4?W?m^?2 (out of 192?W?m^?2), after known bias errors are removed. Similarly, the uncertainty of the annual global surface upward longwave and shortwave is, respectively, 3?W?m^?2 (out of 398?W?m^?2) and 3?W?m^?2 (out of 23?W?m^?2). The uncertainty is for modeled irradiances computed using cloud properties derived from imagers on a sun-synchronous orbit that covers the globe every day (e.g., moderate-resolution imaging spectrometer) or modeled irradiances computed for nadir view only active sensors on a sun-synchronous orbit such as Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation and CloudSat. If we assume that longwave and shortwave uncertainties are independent of each other, but up- and downward components are correlated with each other, the uncertainty in global annual mean net surface irradiance is 12?W?m^?2. One-sigma uncertainty bounds of the satellite-based net surface irradiance are 106?W?m^?2 and 130?W?m^?2.     

Relationships between the Concentrations of Phyto-Pigments,Nitrogen, and Phosphorus in Bottom Deposits of Water Reservoirs

Samples characterizing the horizontal distribution of bottom deposits of different types in the Upper Volga reservoirs were used to study the statistical relationship between the indicators of the potential and actual trophy of water bodies. These indicators are the amount of biogenic elements (the total nitrogen and phosphorus) and phyto-pigments (in the dry and wet masses of soil and in its organic fraction). The relationship between the above indicators for the channel deposits from the Upper Volga reservoirs and for the deposits in the lake hollows is found to he linear.     

Interpretation of SOFIE PMC measurements: Cloud identification and derivation of mass density,particle shape,and particle size

The Solar Occultation For Ice Experiment (SOFIE) was launched onboard the Aeronomy of Ice in the Mesosphere (AIM) spacecraft to measure polar mesospheric clouds (PMCs) and their environment. This work describes methods for identifying PMCs in SOFIE observations and determining mass density, particle shape, particle effective radius, and the parameters of a Gaussian size distribution. Results using SOFIE measurements from the northern summer of 2007 are compared with concurrent observations by the ALOMAR lidar in northern Norway. Ice particle properties determined from SOFIE are in good agreement with the lidar results, considering the differences in instrument characteristics.     

Frequency-Magnitude Relationships for seismic areas around the capital cities of Solomon, Vanuatu, Tonga and Fiji Islands

We studied the relationships between the frequency ofoccurrence and the magnitudes in seismogenic areasthat will affect four capital cities in the SouthPacific, namely: Honiara in Solomon Islands, Port Vilain Vanuatu, Suva in Fiji and Nuku'alofa in Tonga. Weused the NEIS catalogues for the period 1973–1997, formagnitudes greater than about 5, in the proximity tothe city under investigation. The definitions of thegeographic boundaries of the seismogenic zones arebased on the classical concepts of the distribution ofthe tectonic plates, the overwhelming number ofstudies that describe the seismotectonics in thoseactive regions and on the observed seismicity andstudies of the local people. Completeness of thecatalogue is assumed because of the high seismicity inthese areas, despite the relatively short time span.We have used a hybrid process combining least squaresfitting and Newtonian search process to find the bestfit of the statistical parameters. The characteristicb value is 1.27, and seems to be irrespective of thedepth and/or region.     

Antibiotic Resistance and Plasmid Profiles of Vibrio Isolates from Cultured Silver Sea Bream, Sparus sarba

A total of 51 potential pathogenic vibrios were isolated from moribund silver sea bream (Sparus sarba) collected from fish farms in Hong Kong. Using the API 20E system and the scheme of Alsina and Blanch (1994), 7 species were identified from all isolates. These species were Vibrio alginolyticus (24 strains), Vibrio vulnificus (12 strains), Vibrio parahaemolyticus (7 strains), Vibrio logei (4 strains), Vibrio pelagius II (2 strains), Vibrio fluvialis (1 strain) and Vibrio meditterranei (1 strain). The three dominant species (V. alginolyticus, V. vulnificus and V. parahaemolyticus) were confirmed to be virulent to sea bream by experimental challenge.

All isolates were screened for plasmid DNA by agarose gel electrophoresis and tested for susceptibility to 16 antibiotics by the agar dilution method. Of the 51 isolates examined, all strains were sensitive to ceftriaxone, streptomycin, nalidixic acid and rifampicin, and almost all were sensitive to ceftazidime, netilimicin, chloramphenicol and sulfamethoxazole. Most isolates were resistant to ampicillin (60.8%), cefuroxime (66.7%), amikacin (55%), kanamycin (58.8%) and trimethoprim (76.5%). Fifteen of the 51 isolates harboured 1–4 plasmids, with sizes ranging from 9 to 123 kb. Both the plasmids and the associated antibiotic resistance (ampicillin, cefuroxime and trimethoprim) of 9 isolates could be transferred to a recipient by single-step conjugation. However, the frequencies were very low, ranging from 10⁻¹¹ to 10⁻⁹. The present results indicate that resistance to these antibiotics is chromosomal.