COMPARING TWO MEASURES OF WATER BASED RECREATION PARTICIPATION1

ABSTRACT: Site specific studies of water based recreation participation are intended to describe use at a particular recreation area. Two common strategies employed in site specific studies are the on-site “entry” or “exit” survey and the off-site mailed questionnaire to known users of an area. Previous research has reported differences in psychological perceptions of a recreation engagement depending on whether a survey was administered during or after a trip. If such bias exists for behavioral reports, then managers and planners must be cautious in interpreting results of survey based use assessments for a particular site. Findings may be affected by the particular survey strategy employed. In this study, entry point and post-trip mailed questionnaire measures of water based recreation participation were compared for a sample of reservoir users. For most activities, a high degree of consistency in measures was found. Inconsistent reports were most likely to occur among participants in activities sharing significant common behaviors, such as power boating and water skiing. Inconsistency was also observed for those reporting very generalized behaviors, such as relaxing. In general, the use of either pre- or post-trip measures of water based recreation participation was supported.     

Secchi Disc Relationships1

ABSTRACT: The problem of estimating bulk light extinction coefficients in surface water impoundments is examined. It is shown that the bulk extinction coefficient can be accurately estimated from the Secchi disc depth. In addition, the equation derived is significantly different from that derived by Poole and Atkins in 1929. This empirical expression for the extinction coefficient is then used to develop a semiempirical expression for the euphotic depth as a function of the Secchi disc depth.     

MANAGING CRISIS: THE EFFECTIVENESS OF LOCAL DISTRICTS FOR CONTROL OF GROUND WATER MINING1

: This article examines the willingness and capacity of local districts to control ground water mining of the Ogallala Aquifer in the High Plains. The questions of willingness and capacity were approached through extensive field interviews and a survey of all district board members and managers. The analysis focuses on the policy alternatives board members and managers perceive and how they evaluate these alternatives. Methodologically, the study utilized factor analysis of responses rating the desirability of various policy alternatives to ascertain what alternatives were perceived by the sample. Then the sample's preferences for each of the identified factors were calculated. The results demonstrate that the sample of those who must regulate if ground water mining is to be controlled at the substate level are not oriented to regulatory policies and therefore lack the willingness to deal with ground water mining.     

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.     

Forest management policies and elk summer carrying capacity in theAbies amabilis forest,western Washington

Effects of different forest management policies on long-term vegetation development are incorporated into a computer simulation of a western Washington watershed. The response of a Rocky Mountain elk(Cervus canadensis nelsoni) population to these vegetation changes is simulated using information on their differential use of vegetation types. Simulations include: 1) a cessation of timber harvesting leading to an immediate decline in elk members resulting from a reduction in summer habitats; 2) a stable elk population, similar to the present one, resulting from a constant timber harvesting rate, and 3) initial increases in herd size, followed within 50 years by a sharp decrease, resulting from cutting all old growth timber within the next decade and then a cessation of timber harvestings.     

SITING OF A WATER POLLUTION CONTROL FACILITY AT JAMESTOWN,RHODE ISLAND1

ABSTRACT: The town of Jamestown, Rhode Island, located on Conanicut Island in Narragansett Bay, is constructing a secondary treatment plant in order to comply with NPDES regulations. Twelve candidate sites for the plant and marine outfall were initially proposed, and ability to meet State water quality standards at these sites was evaluated using an EPA buoyant plume model. A final outfall site, Taylor Point, was selected by the Town from among the sites considered acceptable. Taylor Point was then subjected to field hydrographic studies including drogue tracking, current recordings, and tracer dye surveys. Results of the measurement program served as input to a two-dimensional effluent dispersion model which predicted excess BOD, coliform, and suspended solids resulting from effluent discharge off Taylor Point. The model predictions demonstrated that State water quality standards can be maintained outside the initial discharge plume.     

EVALUATION OF HYDROLOGIC MODELING TECHNIQUES FOR FOREST LAND MANAGEMENT PLANNING1

ABSTRACT: A growing concern for environmental quality paralleled with increasing demands on our forest resources has prompted the Washington State Department of Natural Resources to evaluate simulation modeling as a technique for analyzing management decisions in terms of their environmental effects. The evaluation focused on a system of integrated models developed at the University of Washington which simulate processes and activities within the forest ecosystem. A major part of the system is a hydrologic model which predicts changes in discharge, stream temperature, and concentrations of suspended sediment and dissolved oxygen based on information generated by other models representing intensive management practices. The evaluation consisted of applying the system to a 72,000 acre tract of forest land, validating the models with two years of discharge and water quality data from a 93,000 acre watershed, and determining the pertinence of hydrologic modeling for management purposes. Results show several potential uses of hydrologic modeling for forest management planning, especially for analyzing the effects of timber harvesting strategies on water quality.