Application of GNSS-RTK derived topographical maps for rapid environmental monitoring: a case study of Jack Finnery Lake (Perth, Australia)

In environmental monitoring, environmental impact assessments and environmental audits, topographical maps play an essential role in providing a means by which the locations of sampling sites may be selected, in assisting with the interpretation of physical features, and in indicating the impact or potential impact on an area due to changes in the system being monitored (e.g., spatially changing features such as wetlands). Global Navigation Satellite Systems (GNSS) are hereby presented as a rapid method for monitoring spatial changes to support environmental monitoring decisions and policies. To validate the GNSS-based method, a comparison is made of results from a small-scale topographic survey using radio-based real-time kinematic GNSS (GNSS-RTK) and total station survey methods at Jack Finnery Lake, Perth, Australia. The accuracies achieved by the total station in this study were 2 cm horizontally and 6 cm vertically, while the GNSS-RTK also achieved an accuracy of 2 cm horizontally, but only 28 cm vertically. While the GNSS-RTK measurements were less accurate in the height component compared to those from the total station method, it is still capable of achieving accuracies sufficient for a topographic map at a scale of 1:1,750 that could support environmental monitoring tasks such as identifying spatial changes in small water bodies or wetlands. The time taken to perform the survey using GNSS-RTK, however, was much shorter compared to the total station method, thereby making it quite suitable for monitoring spatial changes within an environmental context, e.g., dynamic mining activities that require rapid surveys and the updating of the monitored data at regular intervals.     

INACTIVATION OF GIARDIA MURIS CYSTS BY CHLORAMINES1

ABSTRACT: In a study to measure the efficacy of chioramines at inactivating Giardia cysts, the ability of cysts to excyst was measured after exposure to different concentrations of chloramines, for different times, and at different temperatures and pH. The chloramines were generated by mixing ammonium sulfate and sodium hypochlorate in water to approximate a 7:1 chlorine:ammonia ratio by weight. Times of 40, 80, 180, and 270 minutes; temperatures of 3, 10, and 18°C; target chioramine concentrations of 0.4, 1.4, 2.0, and 2.6 mg/L; and pH of 7.0 and 8.5 were the actual values tested. The combinations of these variables that were able to inactivate >99.8 percent of the cysts were a minimum chloramine concentration of 2.26 mg/L applied for 270 minutes at a water temperature of 10°C; and at 18°C, averaged minimum chloramine concentrations of 2.14 and 1.55 mg/L applied for 180 and 270 minutes, respectively. The minimum CT values corresponding to these combinations capable of >99.8 percent cyst inactivation, are 610 at 10°C and 385 at 18°C. Temperature was noted to exert a major effect on the ability of chloramines to inactivate cysts. Modifications of the methods used to generate chloramines may have an effect on the capacity of this disinfectant to inactivate cysts.     

Integrated management of ash from industrial and domestic combustion: a new sustainable approach for reducing greenhouse gas emissions from energy conversion

Environmental Science and Pollution Research - This work supports, for the first time, the integrated management of waste materials arising from industrial processes (fly ash from municipal solid...     

Influence of sponges on invertebrate recruitment: A field test of allelopathy

We manipulated live sponges in Belize, Central America, Big Pine Key, Florida (USA), and Indian River lagoon, Florida (USA) in summer/autumn, 1988. At each location, live sponges of three species were placed within 0.5 cm of ceramic tiles. Tiles with synthetic sponges positioned in the same manner and tiles with no sponges served as controls. Of 26 recruiting species analyzed, only one (Sponge sp. 6 — Indian River) was inhibited by living sponges. Four species (Perophora regina — Belize;Aiptasia pallida — Big Pine Key; andCrassostrea virginica andAscidia nigra — Indian River) recruited in greater numbers in the presence of sponges, suggesting that some larvae may be attracted rather than repelled by sponge allelochemicals. Allelopathic effects were less important than small-scale flow effects and patchy larval supply in determining recruitment patterns on surfaces adjacent to sponges.     

A new method to inertize incinerator toxic fly ash with silica from rice husk ash

Fly ash from municipal solid waste incineration is a toxic waste due to the presence of toxic heavy metals. Here, a new method for metal stabilization based on the use of silica gel extracted from rice husk ash is presented. This method is sustainable because of the use of only waste materials to produce a final inert product, and because the inertization procedure occurs at room temperature. The estimated maximum Pb adsorption capacity of extracted silica, of about 36 mg/g, is found to be far greater than the adsorption capacity of other known absorbers used for municipal solid waste incineration fly ash.     

Driving exposure by driver age in Michigan

Background

This study compared driving exposure between two high-crash-risk groups (16–17 and 18-24-year-olds), with a low-crash-risk group (35-64-year-olds). In addition, patterns of association between driving exposure measures and demographic and driving behavior variables were examined.

Methods

Respondent's total miles, minutes, and trips driven were calculated within a 48-hour period, using state-wide survey data collected in 2004 and 2005.

Results

The youngest drivers drove fewer miles and minutes, but a comparable number of trips as the two older groups. Employment and high vehicle access were associated with greater driving exposure for 16-17-year-olds and 18-24-year-olds. Employment, high household income, large household size, and low vehicle access were associated with greater driving exposure for 35-64-year-olds. More driving was done alone than with passengers present and during the day than at night across all ages. There was a positive association between two driving exposure measures (miles and minutes driven) and demographic and driving behavior variables, which did not extend to trips driven.

Discussion

Driving exposure is directly related to stage of life. The entire sample of 16-17-year-old respondents were in high school, which directly influenced their driving times, destinations, and purpose. Those aged 18–24 years displayed driving behavior patterns that were closer to the older drivers, while retaining some differences. The oldest drivers were likely to be shouldering the greatest household responsibilities, and their greater driving exposure may reflect this reality.

Impact on industry

These findings provide new information about driving exposure for two high-risk and one low-risk group of drivers. They also raise concern over potential workplace safety issues related to teens’ higher driving exposure, and concomitant crash risk, related to being employed. Future research should examine this issue more carefully so that evidence based recommendations can be made to enhance the safety of teens who are employed, especially those who are employed as drivers.     

Mitigation of Habitat "Take": Application to Habitat Conservation Planning

One of the most important provisions of the U.S. Endangered Species Act precludes the "taking" of listed species on both public and private land. In past Endangered Species Act litigation, take has been broadly interpreted to include the destruction or modification of habitats as well as the direct killing of animals. This requirement created an extensive burden on private landowners to provide habitats for listed species. This burden was substantially lessened when the ESA was modified in 1982 to allow incidental takings conditioned on preparation of a satisfactory "habitat conservation plan." Because the majority of listed species are imperiled due to habitat modification, most habitat conservation plans must demonstrate defensible methods to mitigate against incidental habitat loss. A review of HCPs for the Northern Spotted Owl ( Strix occidentalis), and other species, indicates that mitigation solutions are often arbitrary, lacking an empirical foundation in the species' life history requirements. Based on data from the Spotted Owl, we illustrate a biologically based method for estimating the areal requirements necessary to mitigate against the take of essential habitats. Toward this goal we adopt the concept of "core area," that portion of an animal's home range that receives disproportionate use. We estimated core areas by means of the adaptive kernel density function and tested against a null distribution of animal use that assumes a bivariate, uniform distribution of locations within the home range. The method we illustrate, which is defensible, repeatable, and empirical, is a clear improvement over the ad hoc methods used in many habitat conservation plans. Further, the methods we propose should be applicable to a large number of terrestrial species for which home range is a meaningful concept.