Policy And Practice Improving EIA for Intensive Livestock Projects

Agriculture is being increasingly integrated into the UK's land use planning system and recently approved amendments to the EU's Environmental (Impact) Assessment Directive will further this integration and cause more assessments of more projects on a mandatory basis. This paper reviews recent research on the quality of assessments and argues that Environmental Statements of agricultural projects are of a much lower standard than those for other project types and that improvements will need to be made as a result of the changes to the Directive.     

A model and design equations for the intermittent sand filter

Design parameters based upon influent suspended (SS) and volatile suspended solids (VSS) concentrations and hydraulic loading rates were evaluated. Functional relationships and coefficients describing the efficiency of the ISF process were developed based upon laboratory data from filter units containing 0.17 mm effective sand size (ε′) media. Adequate SS and VSS removals were observed for the 0.17 mm ε′ sand filters. Field data from other studies using filter units containing 0.17, 0.40, and 0.68 mm ε′ sand were also evaluated using the model. Sand sizes larger than 0.17 mm ε′ did not produce effluents satisfying a federal secondary standard of 30 mg/1 of SS when the filter influent suspended solids were predominantly algae.     

Vegetation and soil recovery in wilderness campsites closed to visitor use

Recreational use of wilderness results in impacts to vegetation and soil in trails and campsites. Traditionally, campsite impact studies have compared campsites receiving various levels of use with unused control areas. Field studies in Sequoia National Park, California, indicate that the degree of impact to vegetation and soils also varies within campsites. The central areas of campsites, where trampling is concentrated, show lower plant species diversity, differences in relative species cover, more highly compacted soils, and lower soil nutrient concentrations than do peripheral, moderately trampled, and untrampled areas within the same campsite. Three years after closure to visitor use, the central areas show less increase in mean foliar plant cover, and soils remain more highly compacted than in previously moderately trampled areas of the same sites. Changes in relative species cover over time are used to assess both resiliency to trampling and species composition recovery within campsites closed to visitor use.     

BENEFITS OF POLLUTION CONTROL ON MASSACHUSETTS’ HOUSATONIC RIVER: A HEDONIC PRICING APPROACH1

ABSTRACT: This paper illustrates one mode of analysis for estimating the benefits of water pollution control projects. Results indicate regional benefits associated with an abatement program instituted for point source pollution along the Housatonic River during the 1960's were substantial. Studies of this kind can aid regulatory and recreation resource administrators in devising and evaluating environmental programs.     

Wind speed affects prey-catching behaviour in an orb web spider

Wind has previously been shown to influence the location and orientation of spider web sites and also the geometry and material composition of constructed orb webs. We now show that wind also influences components of prey-catching behaviour within the web. A small wind tunnel was used to generate different wind speeds. Araneus diadematus ran more slowly towards entangled Drosophila melanogaster in windy conditions, which took less time to escape the web. This indicates a lower capture probability and a diminished overall predation efficiency for spiders at higher wind speeds. We conclude that spiders’ behaviour of taking down their webs as wind speed increases may therefore not be a response only to possible web damage.