The primary aerobic biodegradation of biodiesel B20

We describe the primary aerobic biodegradation of a B20 fuel (20% soybean fatty acid methyl esters, 80% petroleum diesel) by unacclimated inocula from a rainwater detention pond. Biodegradation was rapid and essentially complete, with an overall median 'half-life', at approximately 100 ppm B20, of 6.8 days (n=34). Using purge-and-trap and extraction methodologies, both coupled to GC/MS, and hexachloroethane and hexachlorobenzene as conserved internal markers in the B20, we followed the biodegradation of total detectable material, 76 individual analytes and eight undifferentiated groups of isomers, and calculated their half-lives under these conditions. The fatty acid methyl esters, n-alkanes and iso-alkanes, and simple and alkylated aromatic compounds were the most readily degraded compounds, followed by the naphthenes. The last (identified) compounds to be degraded were ethylalkanes, trisubstituted cyclohexanes and decalins, but even these disappeared with an apparent 'half-life' of <30 days.     

Natural disasters and older US adults with disabilities: implications for evacuation

We analysed 2003 and 2004 Behavioral Risk Factor Surveillance System (BRFSS) data from New Orleans-Metairie-Kenner, LA to produce estimates of the number of community dwelling people aged 65 years or older with a disability and requiring special equipment.(4) Approximately, 47,840 (31.6 per cent) older adults with a disability and 24,938 (16.6 per cent) older adults requiring the use of special equipment were community dwelling and might require assistance to evacuate or a shelter that could accommodate special equipment. Older adults who need special equipment were likely to be female, unmarried and white, and to rate their health as fair or poor. Personnel who plan and prepare for evacuations and temporary shelter during disasters need baseline information on the number of older adults with a disability or who require special equipment. A surveillance system, such as the BRFSS, gathers information that planners can use to prepare for and to deliver services.     

Factors Influencing Movement Patterns of Keel-Billed Toucans in a Fragmented Tropical Landscape in Southern Mexico

Abstract: Various factors influence animal movements in fragmented landscapes, and determining these factors is key to understanding ecological processes at a landscape scale. My goals were (1) to determine what factors influence movements of Keel-billed Toucans (    Ramphastos sulfuratus ) in a fragmented landscape in southern Mexico and (2) to use this information to predict how movement patterns might change if the landscape was altered. I developed a cost-distance geographic information system model that adjusts Euclidean distances by a cost of moving through a certain habitat type. Cost was based on habitat preferences exhibited by toucans. I then used this model to predict how movements might be affected by removal of isolated trees and living fences from the pasture matrix and by removal of forest remnants. Toucans moved more frequently between remnants separated by a low cost-distance value. There was a cost-distance threshold beyond which movements between remnants were rare. Below this threshold, fruit abundance influenced toucan movements but remnant area was not influential in that toucans did not preferentially move to large patches. Remnants close to various other remnants were more frequently visited by toucans, indicating that landscape connectivity influences toucan movements. Toucans incurred a 10–30% cost increase when moving in computer-simulated landscapes, indicating that changes in forest cover or configuration of habitats may negatively affect toucan populations, assuming that increased cost has a fitness consequence. Cost-distance modeling has been relatively unexplored and may be a valuable tool for determining how the configuration of a landscape impedes or facilitates animal movements.     

Developing a circumpolar programme for the monitoring of Arctic terrestrial biodiversity

The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.     

Applicability of polar organic compound integrative samplers for monitoring pesticides in groundwater

Polar organic chemical integrative samplers (POCISs) for the monitoring of polar pesticides in groundwater were tested on two sites in order to evaluate their applicability by comparison with the spot-sampling approach. This preliminary study shows that, as in surface water, POCIS is a useful tool, especially for the screening of substances at low concentration levels that are not detected by laboratory analysis of spot samples. For quantitative results, a rough estimation is obtained. The challenge is now to define the required water-flow conditions for a relevant quantification of pesticides in groundwater and to establish more representative sampling rates for groundwater.     

Rapid Nitrate Loss from PM10 Filters

The Monterrey Metropolitan Area (MMA) has shown a high concentration of PM_2.5 in its atmosphere since 2003. The contribution of possible sources of primary PM_2.5 and its precursors is not known. In this paper we present the results of analyzing the chemical composition of sixty 24-hr samples of PM_2.5 to determine possible sources of PM_2.5 in the MMA. The samples were collected at the northeast and southeast of the MMA between November 22 and December 12, 2007, using low-volume devices. Teflon and quartz filters were used to collect the samples. The concentrations of 16 airborne trace elements were determined using x-ray fluorescence (XRF). Anions and cations were determined using ion chromatography. Organic carbon (OC) and elemental carbon (EC) were determined by thermal optical analysis. The results show that Ca had the maximum mean concentration of all elements studied, followed by S. Enrichment factors above 50 were calculated for S, Cl, Cu, Zn, Br, and Pb. This indicates that these elements may come from anthropogenic sources. Overall, the major average components of PM_2.5 were OC (41.7%), SO₄ ^2? (22.9%), EC (7.4%), crustal material (11.4%), and NO₃ ^? (12.6%), which altogether accounted for 96% of the mass. Statistically, we did not find any difference in SO₄ ^2? concentrations between the two sites. The fraction of secondary organic carbon was between 24% and 34%. The results of the factor analysis performed over 10 metals and OC and EC show that there are three main sources of PM_2.5: crustal material and vehicle exhaust; industrial activity; and fuel oil burning. The results show that SO₄ ^2?, OC, and crustal material are important components of PM_2.5 in MMA. Further work is necessary to evaluate the proportion of secondary inorganic and organic aerosol in order to have a better understanding of the sources and precursors of aerosols in the MMA.

Implications: The MMA has become one of the most air polluted areas in Mexico. High levels of PM_2.5 have been measured and effective actions need to be taken to reduce air pollution and the associated health risks. Several sources of primary PM_2.5 and precursors of secondary particles exist in the MMA. This study provides valuable information for the local environmental authorities to identify possible sources of primary PM_2.5 and its precursors. The effectiveness of the actions taken to improve air quality will lead to health benefits for the population, reducing their associated costs.     

Valorization of fish by-products: rheological,textural and microstructural properties of mackerel skin gelatins

The fish processing industry generates significant amounts of waste which is usually discarded. The present study investigated the recovery of gelatins from Atlantic mackerel (Scomber scombrus) skins after pre-treatment with different environmentally friendly organic acids (acetic, citric, lactic, tartaric or malic acid). The chemical composition, the rheological and the textural properties as well as the microstructural characteristics of the extracted gelatins were analysed and compared to commercial bovine hide gelatin. Although the organic acid used in the pre-treatment step did not affect the extraction yield and the chemical composition of the prepared gelatins, differences were observed in terms of rheology and texture. The highest gel strength (P < 0.05) was observed with gelatins extracted after pre-treatment with acetic, citric and malic acids (71–80 g). From an industrial point of view, gelatin can be extracted using any of these organic acids with similar yield. However, in order to obtain better rheological and textural properties the use of acetic, citric or malic acid in the pre-treatment step is recommended.