Maturity,fecundity, and reproductive cycle of the spotted ratfish, <Emphasis Type="Italic">Hydrolagus colliei</Emphasis>

Size at maturity, fecundity, and reproductive periodicity were estimated for the spotted ratfish, Hydrolagus colliei (Lay and Bennett, 1839), off the coast of California, Oregon, and Washington. Maximum body size and size at median maturity were greater for females than males. Skeletal muscle concentrations of the steroid hormones testosterone (T) and estradiol (E₂) predicted similar, but slightly smaller sizes at maturity than the morphological criterion. Stage of maturity for males was estimated identically using internal organs or external secondary sexual characters, thus allowing non-lethal maturity assessments. Size at median maturity was greater north of Point Conception for females, and north of Cape Mendocino for males. Peak parturition occurred from May to October, with increased concentrations of E₂ in skeletal muscle of females correlating with ovarian recrudescence during November to February. No significant seasonal trends in female T were apparent, but mean female 11-ketotestosterone (11KT) was 300% greater in April than any other month during the parturition season. There was a marginal evidence for increased number and size of ova with maternal size. Extrapolation of the hypothesized 6 to 8-month egg-laying season to observed mean parturition rates of captive specimens yielded an estimated annual fecundity of 19.5–28.9 egg cases. Differences in fecundity among higher taxonomic classifications of chondrichthyans were detected with chimaeriform fishes more fecund than lamniform, myliobatiform, squaliform, and rhinobatiform fishes, and less fecund than rajiform fishes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

A Field Demonstration of the UV/Oxidation Technology to Treat Ground Water Contaminated with VOCs

This paper presents the Geld evaluation results of the ultraviolet radiation (UV)/oxidation technology developed by Ultrox International, Santa Ana, California. The Geld evaluation was performed at the Lorentz Barrel and Drum (LB&D) site in San Jose, California, under the Superfund Innovative Technology Evaluation program in February and March of 1989.

The UV/oxidation technology uses UV radiation, ozone, and hydrogen peroxide to oxidize organic contaminants present in water. At the LB&D site, this technology was evaluated in treating ground water contaminated with volatile organic compounds (VOCs). The Ultrox system achieved VOC removals greater than 90 percent. Most VOCs were removed through chemical oxidation. However, for a few VOCs, such as 1, 1, 1-trichloroethane and 1, 1-dichloroethane, stripping also contributed toward removal. The treated ground water met the applicable discharge standards for discharge into a local waterway at 95 percent confidence level. There were no harmful air emissions to the atmosphere from the Ultrox system, which is equipped with an off-gas treatment unit.     

Monopoly exploitation of an exhaustible resource

The popular notion that a monopolist will exhaust a nonrenewable natural resource at a slower than socially optimal rate is examined. Contrary to the prevailing belief, instances do exist for which the monopolist uses the resource faster than the social maximizer. This is demonstrated first by finding conditions for which the expected result—a monopoly rate which is slower than optimal-will always hold, and second, by showing that for situations where these conditions are violated the result may be reversed.     

Life cycle assessment of DRAM in Taiwan's semiconductor industry

The semiconductor industry plays a leading role in supporting economic stabilization and social progress in Taiwan. In this paper, Eco-indicator 95 and Impact 2002+ are utilized to evaluate the potential environmental impacts from five production processes of the double data rate synchronous dynamic random access memory (DDR SDRAM). The comparisons between these two impact methods and their scopes are also discussed.From our results, global warming potential and non-renewable energy consumption were identified as the major environmental impacts. Applications of Eco-indicator 95 and IMPACT 2002+ also suggest that summer smog and respiratory inorganics are significant impact categories. The comparison of the scopes of these two methods identifies that low GWP potential PFCs substitution and electricity saving are effective ways to decrease environmental impacts of DRAM manufacturing. In addition, IMPACT 2002+ is a more applicable LCA method for the semiconductor industry in Taiwan due to the structure and reference area of this method and the characteristics of the semiconductor industry in Taiwan.     

Natural disaster mitigation: Environmental approaches in Tonga and Algeria

Summary The mitigation of natural disasters essentially depends upon the identification and adjustment of human ecological processes contributing to conditions of vulnerability. The analysis of vulnerability requires the local study of political, social, and economic processes which have contributed, and are contributing, to a vulnerable condition in a hazardous environment. One of the few similarities between Tonga and Algeria is a continuing experience of natural disaster after independence from previous colonial administrations. In two very different but complementary projects, ways are identified for the adjustment of assumed or inherited priorities for development, to take practical account of continuing hazards. The high vulnerability of rural areas is a factor common to both countries, as well as to many others. The analysis of conditions and systems in two dissimilar countries may have begun a process of implementation, one which must necessarily follow theoretical analysis for the realisation of practical value. The degree and nature of disaster impact is conditioned as much by normally prevailing conditions and systems as by the manifestation of natural hazard. Direct experience of hazardous environments, and of problems caused by disaster, must be made to result in the creation of multi-disciplinary environmental policies for disaster mitigation, inclusive of small scale development and education and training programmes for continued implementation. Comprehensive and simultaneous strategies for disaster avoidance, disaster resistance, and disaster accomodation must be made integral components of local development planning.     

Change,and vulnerability to natural hazard: Chiswell,dorset

Summary The occurrence of disastrous manifestations of hazard are not usually unique events. In analysis of the causes and effects of these occurrences there are problems for analysts, academics and policy-makers in the understanding of long-term perspectives as the context for recent events and future policies. Understanding will be made initially, but necessarily, more complex by the variety of standpoints of different interest groups in the affected community, and of the community at large. Physical permanence of a community cannot beassumed in a changing environmental condition. Vulnerability to the sea has increased during the thousand years of Chiswell's existence, and is continuing to do so. Understanding of this changing state by various groups in society, and their administrators, is the key to the selection and effectiveness of interacting social and technological measures whether undertaken specifically against hazard or not. The extent to which technology can be effectively mobilised and implemented to ensure prolonged community permanence may only be assessed by detailed analysis of environmental phenomena on the one hand, and by comparison with social adjustments on the other. Social adjustments cannot be compared until those options are made realistically available by the authorities elected for their administration. The condition of vulnerability is not static. Analysis and assessment of short- and longer-term issues is at once a multi-disciplinary process calling for a fusion of physical and earth sciences, social sciences, and political and administrative processes. That these sciences and processes are themselves evolving, and are not static, is as true as for vulnerability itself. That all are in short- and long-term processes of change must be understood if each is to be integrated with the other for maximum comprehensive and effective response to natural hazard.