APPLICATION OF SELECTED SOIL LOSS EQUATIONS TO TRAMPLED SOIL CONDITIONS1

ABSTRACT: Soil loss prediction equations (Universal Soil Loss Equation, Modified Universal Soil Loss Equation, and Onstad-Foster Method) were modified to reflect the impact of trampling on soil erosion. The erosion control practice factor, P, was replaced by a trampling ratio, Tr, which is a function of the change in soil erosion due to animal trampling. Trampling impact on soil erosion varied With soil type. The data are a preliminary attempt to account for the impact of trampling on soil erosion.     

And keep on looking: A film to reduce pedestrian crashes among 9 to 12 year olds

A pedestrian safety education film titled And Keep on Looking and aimed at children ages 9 to 12 was evaluated in several cities. The results showed an increase in safe street crossing knowledge among 9- to 12-year-old Connecticut children who viewed the film, and some improvement in safe street crossing behavior among 9- to 12-year-old Seattle, Washington, children. Crash reduction was assessed in a 2-year, citywide field test conducted in Milwaukee. The field test indicated a crash reduction of more than 20% for 9- to 12-year-old children in Milwaukee compared with children in areas surrounding Milwaukee and children in comparison cities.     

Theoretic model for the computer analysis of vehicle collisions

The complexity of the study and reconstruction of traffic accidents justifies the creation of tools which make easier the research in this area. That is the reason why the GIVET has developed a program called SINRAT III that lets, by means of dynamic simulation, reproduce the evolution of two vehicles in an accident in which a collision takes place, letting analyze the precollision and postcollision movements, as well as studying what happens during the contact and deformation of the vehicles in the collision stage. The simulation model is integrated by bodies developed using the bond-graph technique, that allows the simulation of the dynamic behaviour of the vehicles in any circumstance. At the end of this paper, an application example is presented, corresponding to an accident with collision between car and coach.     

Metals recycling in the United States

Twenty-two metals for which secondary recovery is important, in terms of quantity and/or value, were compared and ranked for rate and efficiency of recycling, and availability of recycled metal. In general, their recycling rates trended upward over the period 1970–1993. Iron, aluminum, copper, gold, platinum, and lead accounted for most of the value of all secondary metal produced, while iron and steel dominated in terms of quantity produced and exported. The factors most influential on recycling rates are profitability, public support, organization of infrastructure, sortability, legislative support, and scrap purity. The share of supply accounted for by secondary metals is expected to surpass that of primary metals sometime in the next decade.     

A PRELIMINARY QUANTIFICATION OF THE IMPACTS OF ASPEN TO CONIFER SUCCESSION ON WATER YIELD- II. MODELING RESULTS1

ABSTRACT: Heat pulse velocity techniques were developed for effective monitoring of water movement in aspen (Populus tremuloides), subalpine fir (Abies lasiocarpa), and Englemann spruce (Picea engelmannif). Water loss was monitored in replicated trees of each species for one year. These data were used to modify the plant activity index (a reflection of the ability of plants to transpire water at various times during a year) and the crop coefficient (a reflection of differences in consumptive use rates of water by different vegetation types when all other factors are held constant) for each species within the model ASPCON, a deterministic, lumped-parameter model describing the hydrology of aspen to conifer succession. Results of the modeling in dicate 18.6 cm net loss of moisture available for streamflow when spruce replaced aspen, and a loss of 7.2 cm when fir forests replaced aspen. The aspen to conifer successional trend appears, therefore, to be significantly reducing water yields in the western United States.     

Environmental application of aerial reconnaissance to search for open dumps

Three approaches to using aerial photography are evaluated for searching for open dumps in the state of Indiana. Photography with hand-held cameras from a small airplane proved more effective and flexible than either photo-interpretation of existing air photos or subcontracting to a federal agency for new aerial photography. The rationale for our choice of aerial reconnaissance, other uses of low-level aerial surveillance, the utility of small-format camera aerial photography for environmental analysis, and methods used for locating open dumps are discussed.     

SOIL EROSION AWARENESS AND USE OF CONSERVATION TILLAGE FOR WATER QUALITY CONTROL1

Water pollution through loss of topsoil from farmland continues to be a major problem, despite nearly 50 years of providing farmers technical and financial assistance for soil and water conservation. The technology for controlling erosion and water pollution is available, but farmers have been slow in implementing control practices. Past research has shown that farmers tend to be unaware of the seriousness of the erosion problem on their own operations. Using a random sample of farmers from central Iowa, the relationship is examined between awareness of a soil erosion problem and the use of conservation tillage. Results indicate that awareness of a soil erosion problem effects the use of conservation tillage, and that awareness can be enhanced by experiential educational strategies such as the development and implementation of a soil and water conservation plan.     

Rolex Calls for Entries to 11th Awards for Enterprise and Extends Deadlines for All Countries

Call for Papers

Rolex Calls for Entries to 11^th Awards for Enterprise and Extends Deadlines for All Countries     

Reactive nitrogen and public policies for environmental protection

A core goal of both US and European pollution control policies has been to establish rules and regulations pertaining to the movement of reactive-nitrogen (Nr) through the environment. This is manifest in US federal legislation such as the Clean Air Act Amendments and the Clean Water Act Amendments and in various protocols of the United Nations Economic Commission for Europe (UNECE) and its Convention on Long-Range Transboundary Air Pollution (CLRTAP). In this paper, we begin by reviewing the two US laws and their effectiveness and make some comparisons with the approaches used mainly in Europe by the UNECE and CLRTAP. Next we use the Mississippi drainage/Gulf of Mexico hypoxia case study to highlight the importance of applying a "systems approach" to address the reactive nitrogen problem at the regional scale. After briefly posing a number of unanswered questions related to nitrogen control policies, we conclude by sketching a blueprint for future actions related to the development of improved policies to regulate reactive nitrogen.