Assessment of hazards associated with pesticide container disposal and of rinsing procedures as a means of enabling disposal of pesticide containers in sanitary landfills

To study problems associated with pesticide container disposal, a small vegetable production area in southwestern Ontario, the Thedford Marsh, was selected as the site for a model study. A container collection system was organized during the 1981 growing season, with collections being made from the ca. 50 growers on the marsh twice each month. In addition to the regular collection program a cleanup service for empty pesticide containers stored on farms or discarded on public lands also was initiated. More than 3600 containers were collected and disposed of at an authorized landfill site. Ca. 2/3 were herbicide containers, ca. 1/4 were insecticide containers, and 3% were fungicide containers. Unrinsed containers contained as much as 5 1/2% of the original contents with an average of 1%. Containers rinsed by the triple rinse method or using rinsing devices (E-Z Rinse, JET Rinse) generally contained less than 0.1% of the original content. Some formulations presented rinsing problems due to settling and caking. The results indicated that, while unacceptable quantities of pesticide residues remain in unrinsed containers, most rinsed pesticide containers will be acceptable for disposal at municipal sanitary landfill sites.     

Quantitative Pollution Spill Risk Assessment: Using A Gis-Based System

Federal and State agencies have recently advocated risk-based analysis as a mechanism for advancing regulatory reform and safety determination in marine systems. the present investigation promotes this objective through the development of risk-based environmental planning strategies for oil spill contingency plans. This alternative approach to contingency planning departs from conventional methodology by employing quantitative risk assessment methods to identify hazardous oil spill zones and sensitive environmental areas, R_o and R_e respectively. the product of this conversion is referenced on a single “Risk” layer within a Geographic Information System (GIS) framework allowing coastal managers to evaluate natural resource data with associated elements of oil spill risk. As a new tool for coastal pollution management, risk-based environmental planning strategies have shown potential for evolving more efficient oil spill contingency plans.     

Resident Involvement in Natural Resource Management: Open space conservation design in practice

The open space conservation sub-division offers an alternative to large-lot residential sub-divisions often seen as the culprit when urban sprawl transforms rural landscapes. Homes are sited on somewhat smaller lots, preserving natural areas for the local residents who share ownership of these communal areas and assume responsibility for their management. The article focuses on the experiences of residents of 13 relatively new open space communities. The interviews revealed that most of the communities have already confronted conflicting values with respect to natural areas, low resident participation and challenges in accessing appropriate information. While the open space conservation design holds great promise as a tool for innovative approaches to managing residential growth, it also calls for ways to anticipate and assist communities in caring for their local environment. Recommendations are offered for planning professionals based upon the experience of these open space community residents.     

Spatial contrasts of seasonal and intraflock broiler litter trace gas emissions, physical and chemical properties

Comprehensive mitigation strategies for gaseous emissions from broiler operations requires knowledge of the litters' physical and chemical properties, gas evolution, bird effects, as well as broiler house management and structure. This research estimated broiler litter surface fluxes for ammonia (NH3), nitrous oxide (N2O), and carbon dioxide (CO2). Ancillary measurements of litter temperature, litter total N, ammonium (NH4+), total C content, moisture, and pH were also made. Grid sampling was imposed over the floor area of two commercial broiler houses at the beginning (Day 1), middle (Day 23), and end (Day 43) of a winter and subsequent summer flock housed on reused pine shavings litter. The grid was composed of 36 points, three locations across the width, and 12 locations down the length of the houses. To observe feeder and waterer (F/W) influences on the parameters, eight additional sample locations were added in a crisscross pattern among these automated supply lines. Color variograms illustrate the nature of parameter changes within each flock and between seasons. Overall trends for the NH3, N2O, and CO2 gas fluxes indicate an increase in magnitude with bird age during a flock for both summer and winter, but flux estimates were reduced in areas where compacted litter (i.e., caked litter or cake) formed at the end of the flocks (at F/W locations and in the fan area). End of flock gas fluxes were estimated at 1040 mg NH3 m(-2) h(-1), 20 mg N2O m(-2) h(-1), and 24,200 mg CO2 m(-2) h(-1) in winter; and 843 mg NH3 m(-2) h(-1), 18 mg N2O m(-2) h(-1)), and 27,200 mg CO2 m(-2) h(-1) in summer. The results of intensive sample efforts during winter and summer flocks, reported visually using contour plots, offer a resource to the poultry industry and researchers for creating new management strategies for improving production and controlling gas evolution. Particularly, efforts could focus on designing housing systems that minimize extremes in litter compaction. The extremes are undesirable with more friable litter prone to greater gas evolution and more compacted litter providing a slippery, disease-sustaining surface.     

Bigamy and mate choice in the biparental cichlid fish Cichlasoma nigrofasciatum

Summary Sixty percent of C. nigrofasciatum males showed bigamous behaviour when held in small, outdoor ponds at an adult sex ratio of 5 males to 10 females. No male held more than two pair bonds simultaneously. Bigamy had reproductive benefits; bigamous males, on average, fathered more broods that survived well into the free-swimming fry stage than did monogamous males. In ponds where adult size varied, no positive correlations were found, for either sex, between adult size and frequency of spawning or success of broodrearing, despite predictions that larger size would confer reproductive benefits on both sexes. A significant positive correlation was found between the sizes of mated individuals in the pond where both sexes varied in size. On theoretical grounds this relationship is likely to be more strongly influenced by female than by male choice of spawning partner.     

The Lower Susquehanna River Gorge and Floodplain (U.S.A.) as a Riparian Refugium for Vernal, Forest-Floor Herbs

A survey of vernal, forest-understory herbs was conducted on 52 routes, 10 sample sites each, along the Susquehanna River and its major and minor tributaries in southeastern Pennsylvania and northeastern Maryland. Mature forest stands, as compared to younger successional stands, had a greater diversity and cover of native understory herbs and greater frequencies of K -selected species such as Trillium flexipes and Dicentra canadensis . Vernal herbs with a high fidelity to the river corridor were likely to be more mesic in habitat preference, to occupy a more limited range of habitats, and to be less tolerant to disturbance than species that are also common in adjacent upland areas. The best vernal wildflower sites, which are usually in mesic or floodplain forest, may also be the most vulnerable to species loss if the canopy is removed or the forest is otherwise disturbed. Disturbance-sensitive herbs have been nearly extirpated from the Susquehanna tributaries by very intensive human development. Preservation of an appropriate matrix of microhabitats, particularly along the main river and at the mouths of the creeks, is critical to protecting the vernal flora of the region.     

Female choice of mates in a polygynous insect,the whitespotted sawyer Monochamus scutellatus

Summary Adult female whitespotted sawyers Monochamus scutellatus (Coleoptera: Cerambycidae) were placed on succeeding days with two males differing visibly in size. Females showed a significant preference for the larger of two males. The rate of oviposition was significantly higher when the female was paired with the larger male. Both the rate of movement by the paired female and her rate of indicating non-receptivity were significantly lower when the female was paired with the larger male. This species exhibits resource defense polygyny, and females appear to choose mates mainly on the basis of the quality of resources defended. This study suggests, however, that when resource quality is constant, females choose mates on the basis of their size.     

Development of the IM147: an alternative inspection/maintenance mass-emission transient test to address vehicle preconditioning concerns

A series of studies was performed to develop an alternative to the U.S. Environmental Protection Agency's gold standard IM240 mass-based emission test. The new IM147 test was based on the second phase of the IM240 that consists of 147 sec of transient vehicle operation. Paired IM240/IM147 tests were conducted on vehicles ranging from 1981 to 1996 to determine IM147 cutpoints and excess emissions were identified. Additionally, an optimized test procedure was developed that combined possible triplicate IM147s with improved drive trace quality control, fast-pass, and retest methods. The optimized procedure was found to provide improved vehicle preconditioning with a relatively minor decrease in excess emissions identification. Resulting identification rates ranged from 96 to 100% for hydrocarbons (HC), 93-100% for CO, and 93-100% for NOx, depending on cutpoint selection, while false failures caused by lack of vehicle preconditioning were reduced to essentially zero. Significant vehicle throughput improvements were achieved through the development of software algorithms involving modal fast-pass and retest procedures. Modal drive trace variation limits also were developed to improve test accuracy. The combination of the algorithms reduced average IM147 test times by nearly 60%.