Raumbezug und Repräsentativität in der Ökologischen Flächenstichprobe

The quality of regionalizations can only be evaluated with regard to its specific purposes. In environmental monitoring, regionalizations, besides being an analysis tool, has a great importance on the selection of monitoring sites. The article describes the relationship between regionalization, selection procedure and representativeness using the example of Ecological Area Sampling (EAS) and presents the regionalization which was tested in an EAS pilot study.     

Adsorption behavior of 2,4-dichlorophenol and pentachlorophenol in an allophanic soil

The adsorption of 2,4-dichlorophenol (2,4-DCP) and pentachlorophenol (PCP) by a variable-charge soil from southern Chile was studied in a series of batch equilibration experiments. 2,4-DCP and PCP adsorption behavior was evaluated as a function of pH (pH values of 4.5, 6.0 and 7.5) in a 0.1M KCl (25 degrees C) background solution for soil material collected at three different depths (0-20 cm, 20-40 cm, and 40-60 cm). 2,4-DCP and PCP adsorption decreased with increasing soil pH, suggesting that the undissociated species were adsorbed more readily and that electrostatic repulsion may inhibit partitioning as pH increases. The PCP adsorption was greater than observed for 2,4-DCP and decreased with soil depth. Multiple regression analysis between K(d) and various soil properties indicated that the soil organic carbon content is a strong indicator of chlorophenol adsorption, and in addition to organic carbon, the soil pH is an important property controlling adsorption behavior.     

Leaching and half-life of the herbicide tebuthiuron on a recharge area of Guarany aquifer in sugarcane fields in Brazil

This study was undertaken to evaluate the degradation and mobility of the herbicide tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N'-dimethylurea) in soil under field conditions, and its potential for leaching and groundwater contamination. A watershed, Espraiado, located over a recharge area in Brazil, was chosen for soil and water studies. At Espraiado, water samples were collected from seven wells at intervals of three months from March 2004 to June 2006 and analyzed for tebuthiuron. Other samples were taken from city wells located outside of the recharge area. To assess the potential movement to the aquifer, tebuthiuron was also applied to trial plots at the recommended label rate of 1.0 kg/ha a.i. in May of 2004, with and without sugarcane coverage, on sandy soil. Soil samples were collected during the years of 2004 and 2005, at depths intervals of 20 cm from soil surface down to 120 cm and analyzed for tebuthiuron at zero, 3, 30, 60, 90, 120, 150, 180, 240, and 300 days after application. There was no clear effect of sugarcane coverage on the tebuthiuron degradation in soils, but it moved faster into the soil where there was no cover. After 180 days there were no measurable residues in the soil, and tebuthiuron was not found below 40 cm depth in any time. Tebuthiuron had a half-life of 20 days under those conditions. No tebuthiuron residue was found in ground water samples at any sampling time.     

Permanent aggregations of a pelagic predator at shallow seamounts

The effectiveness of marine reserves for highly mobile reef fishes such as jacks and trevallies is normally assumed to be small, even though we generally lack the understanding of their long-term movement patterns. In this work, we combined the analysis of multi-year landings and underwater visual census with acoustic telemetry to investigate the long-term movement patterns (up to 4 years) of almaco jack, Seriola rivoliana, a large reef top predator, in one protected and one unprotected offshore shallow seamount in the Azores, central North Atlantic. Although the analysis of visual census and landing data suggests a pronounced seasonal pattern of occurrence, we found that tagged fish were almost continuously detected at the seamounts for up to four consecutive years. Some individuals showed a few long periods of undetection of 1–2 months in the Formigas reserve, mostly in the fall and winter. Mobility within this seamount increased during spring and summer, and geostrophic current speed was negatively correlated with detection probability. Overall, the acoustic telemetry results showed that adult almaco jacks were resident year-round, refuting the traditional view that these fish are essentially migratory and a seasonal occurrence in the Azores. Given the intrinsic vulnerability of resident fish to fishing, our results highlight the importance of protecting these sites in order to preserve these mature fish aggregations with high reproductive potential.     

Aspergillus sclerotiorum lipolytic activity and its application in bioremediation of high-fat dairy wastewater environments

Oils and grease (O&G) have low affinity for water and represent a class of pollutants present in the dairy industry. Enzyme-mediated bioremediation using biocatalysts, such as lipases, has shown promising potential in biotechnology, as they are versatile catalysts with high enantioselectivity and regioselectivity and easy availability, being considered a clean technology (white biotechnology). Specially in the treatment of effluents from dairy industries, these enzymes are of particular importance as they specifically hydrolyze O&G. In this context, the objective of this work is to prospect filamentous fungi with the ability to synthesize lipases for application in a high-fat dairy wastewater environment. We identified and characterized the fungal species Aspergillus sclerotiorum as a good lipase producer. Specifically, we observed highest lipolytic activity (20.72 U g⁻¹) after 96 h of fermentation using sunflower seed as substrate. The fungal solid fermented was used in the bioremediation in dairy effluent to reduce O&G. The experiment was done in kinetic from 24 to 168 h and reduced over 90% of the O&G present in the sample after 168 h. Collectively, our work demonstrated the efficiency and applicability of fungal fermented solids in bioremediation and how this process can contribute to a more sustainable wastewater pretreatment, reducing the generation of effluents produced by dairy industries.

     

The business cycle and the incidence of workplace injuries: evidence from the U.S.A

Introduction

The current study explored the association between the business cycle and the incidence of workplace injuries to identify cyclically sensitive industries and the relative contribution of physical capital and labor utilization within industries.

Method

Bureau of Labor Statistics nonfatal injury rates from 1976 through 2007 were examined across five industry sectors with respect to several macroeconomic indicators. Within industries, injury associations with utilization of labor and physical capital over time were tested using time series regression methods.

Results

Pro-cyclical associations between business cycle indicators and injury incidence were observed in mining, construction, and manufacturing but not in agriculture or trade. Physical capital utilization was the highest potential contributor to injuries in mining while labor utilization was the highest potential contributor in construction. In manufacturing each effect had a similar association with injuries.

Conclusion

The incidence of workplace injury is associated with the business cycle. However, the degree of association and the mechanisms through with the business cycle affects the incidence of workplace injuries was not the same across industries.

Impact on Industry

The results suggest that firms in the construction, manufacturing, and mining industries should take additional precautionary safety measures during cyclical upturns. Potential differences among industries in the mechanisms through which the business cycle affects injury incidence suggest different protective strategies for those industries. For example, in construction, additional efforts might be undertaken to ensure workers are adequately trained and not excessively fatigued, while safety procedures continue to be followed even during boom times.     

Investigation of Human and Animal Viruses in Water Matrices from a Rural Area in Southeastern Region of Brazil and Their Potential Use as Microbial Source-Tracking Markers

Food and Environmental Virology - This study assessed the sources of contamination of water matrices in a rural area using detection of a host-specific virus (human adenovirus [HAdV], porcine...     

Computer simulation of the coagulation of suspended solids — The applicability of the Müller–Smoluchowski theory

The results of studies carried out using a computer programme simulating the coagulation of suspensions containing spherical sol particles and spherical coagulant particles are reported.The influence of the degree of dispersion of the system on the coagulation reaction kinetics was investigated. The obtained results of kinetic studies were tested in the light of classical Müller–Smoluchowski equations. The influence of the physical properties of the coagulant,such as size, density and mass, on the coagulation rate was tested. It was found that within the range described in this paper, the rate of the simulated coagulation process fulfils both the kinetic equation of a first-order reaction, and the kinetic equation of a second-order reaction.Within the tested range, a significant influence of the mass and size of the coagulant on the coagulation rate was ascertained. The kinetic Müller–Smoluchowski dependence is fulfilled in a broader range of the degree of dispersion, when the coagulant particle mass and the sol particle mass are equal. When the particle mass increases with an increase in the particle radius, the coagulation rate increases faster that it would result from the Müller's dependence.