Cyanide generation during preservation of chlorinated wastewater effluent samples for total cyanide analysis.

Dechlorinating agents and pH adjustment are often used to preserve wastewater samples for cyanide analysis. The effects of four approved preservation protocols on the results of the total cyanide analysis of effluents from four water reclamation plants were examined. The results differed widely, and a clear pattern emerged. Immediate analysis without pH adjustment generally gave total cyanide concentrations below the reporting limit of 5 microg/L, irrespective of the dechlorinating agents used. When the pH was adjusted to > or =12, a slight increase in the measured total cyanide concentration was observed when thiosulfate was used to dechlorinate the samples, and a significant increase (>10 microg/L) was observed when arsenite was used as the dechlorinating agent. These results provide evidence that approved preservation protocols may give rise to cyanide formation in chlorinated wastewater effluent matrices.     

Parental concern about children's traffic safety in residential neighborhoods

One hundred and five parents and nonparents responded to a questionnaire consisting of evaluative ratings (general evaluation, social status and safety concern) of six familiar residential neighborhoods; ratings of the traffic accident risk children in the age ranges 2–4, 5–6, 7–9 and 10–12 years run in these neighborhoods; and, finally, ratings of the strengths attributed to factors as causes of traffic accidents (environment, children, parents, drivers and chance). Across neighborhoods and age ranges of children, risk perceptions were found to be related to the rated strengths of the causes. Low-traffic volume neighborhoods were perceived as less risky and were attributed as less strong causes than high-traffic volume neighborhoods were. Perceived risk increased with age of child to a maximum, then decreased. The same relationship with age was found for the attributed causes environment and drivers. The strength of parents as cause was rated to decrease while the strength of child as cause was rated to increase with age. Chance was rated as the weakest cause and the rated strength did not vary across neighborhoods or age. Neither parentship nor gender, singly or in combination, had any clear effects. For parents and nonparents alike the general evaluation of the neighborhoods was influenced by safety concern but not by the particular aspect investigated, i.e. perceived traffic accident risk to children.     

Impact of air pollution on floral morphology of Cassia siamea Lamk

Cassia siamea plants growing at two different sites (polluted and non-polluted) on two important roads of Agra city exhibited significant differences in their flowering phenology and floral morphology. The flowering in plants growing at polluted site is delayed and there was a marked reduction in flowering density, flowering period, size of floral parts, pollen fertility, fruit and seed-set. SEM observations revealed the presence of well developed glandular structures and reduction in the number and size of large stomata on the anther surface at polluted site. These changes were found to be closely associated with the extent of air pollution caused mainly by significant in the number of automobiles.     

UVR-induced photoinhibition of summer marine phytoplankton communities from Patagonia

During austral summer 2006, experiments were carried out to evaluate the effects of ultraviolet radiation (UVR, 280–400 nm) on carbon fixation of natural phytoplankton assemblages from Patagonia (Argentina). Surface water samples were collected (ca. 100 m offshore) at mid morning using an acid-cleaned (1 N HCl) dark container. The short-term impact of UVR (measured as radiocarbon incorporation) was immediately assessed by exposing samples to three artificial illumination treatments: PAR (400–700 nm), PAR + UV-A (320–700 nm), and PAR + UV-A + UV-B (280–700 nm). Pico-nanoplankton characterized the assemblages, and taxon-specific pigment fingerprinting combined with CHEMTAX and supplemented with microscopic observations showed varied proportions of diatoms, chlorophytes, and cyanobacteria throughout January–February 2006. Photosynthetic efficiency, as assessed through assimilation numbers, was high [between 4.4 and 10.4 μg C (μg chl-a)⁻¹ h⁻¹], and it was probably favored by the supply of inorganic nutrients from the Chubut River. UVR-induced photoinhibition appeared to be related to the taxonomic composition: in general, higher photoinhibition was observed when diatoms dominated, whereas this was lower when samples were dominated by chlorophytes. Our data suggest that xanthophyll pigments might have provided only limited protection in these already highlighted acclimated assemblages.     

Fast removal of heavy metals from water and soil samples using magnetic Fe3O4 nanoparticles

Environmental Science and Pollution Research - Heavy metal discharge from anthropogenic sources on open soil surfaces and in natural water bodies poses serious environmental and health concerns. In...     

Hydrochemical profile for assessing the groundwater quality of Sambhar lake City and its Adjoining area

Quality assessment of water is essential to ensure sustainable safe use of it for drinking, agricultural, and industrial purposes. For the same purpose the study was conducted for the samples of water of Sambhar lake city and its adjoining areas. The standard methods of APHA were used to analysis 15 samples collected from hand pumps and tube wells of the specified area. The analytical results show higher concentration of total dissolved solids, electrical conductivity sodium, nitrate, sulfate, and fluoride, which indicate signs of deterioration but values of pH, calcium, magnesium, total hardness, and carbonate are within permissible limits as per WHO standards. From the Hill-piper trilinear diagram, it is observed that the majority of groundwater from sampling stations are sodium?Cpotassium?Cchloride?Csulfate type water. The values of sodium absorption ratio and electrical conductivity of the groundwater were plotted in the US salinity laboratory diagram for irrigation water. Only the one sample fall in C₃S₁ quality with high salinity hazard and low sodium hazard. Other samples fall in high salinity hazard and high sodium hazard. Chemical analysis of groundwater shows that mean concentration of cation is in order sodium > magnesium > calcium > potassium while for the anion it is chloride > bicarbonate > nitrate > sulfate.     

Compensatory Stream and Wetland Mitigation in North Carolina: An Evaluation of Regulatory Success

Data from a probability sample were used to estimate wetland and stream mitigation success from 2007 to 2009 across North Carolina (NC). “Success” was defined as whether the mitigation site met regulatory requirements in place at the time of construction. Analytical results were weighted by both component counts and mitigation size. Overall mitigation success (including preservation) was estimated at 74 % (SE = 3 %) for wetlands and 75 % (SE = 4 %) for streams in NC. Compared to the results of previous studies, wetland mitigation success rates had increased since the mid-1990s. Differences between mitigation providers (mitigation banks, NC Ecosystem Enhancement Program’s design-bid-build and full-delivery programs, NC Department of Transportation and private permittee-responsible mitigation) were generally not significant although permittee-responsible mitigation yielded higher success rates in certain circumstances. Both wetland and stream preservation showed high rates of success and the stream enhancement success rate was significantly higher than that of stream restoration. Additional statistically significant differences when mitigation size was considered included: (1) the Piedmont yielded a lower stream mitigation success rate than other areas of the state, and (2) recently constructed wetland mitigation projects demonstrated a lower success rate than those built prior to 2002. Opportunities for improvement exist in the areas of regulatory record-keeping, understanding the relationship between post-construction establishment and long-term ecological trajectories of stream and wetland restoration projects, incorporation of numeric ecological metrics into mitigation monitoring and success criteria, and adaptation of stream mitigation designs to achieve greater success in the Piedmont.     

Impact and adaptation opportunities for European agriculture in response to climatic change and variability

Climate change, involving changes in mean climate and climatic variability, is expected to severely affect agriculture and there is a need to assess its impact in order to define the appropriate adaptation strategies to cope with. In this paper, we projected a scenario of European agriculture in a +2°C (above pre-industrial levels) world in order to assess the potential effect of climatic change and variability and to test the effectiveness of different adaptation options. For this purpose, the outputs of HadCM3 General Circulation Model (GCM) were empirically downscaled for current climate (1975–2005) and a future period (2030–2060), to feed a process-based crop simulation model, in order to quantify the impact of a changing climate on agriculture emphasising the impact due to changes in the frequency of extreme events (heat waves and drought). The same climatic dataset was used to compare the effectiveness of different adaptations to a warmer climate strategies including advanced or delayed sowing time, shorter or longer cycle cultivar and irrigation. The results indicated that both changes in mean climate and climate variability affected crop growth resulting in different crop fitting capacity to cope with climate change. This capacity mainly depended on the crop type and the geographical area across Europe. A +2°C scenario had a higher impact on crops cultivated over the Mediterranean basin than on those cultivated in central and northern Europe as a consequence of drier and hotter conditions. In contrast, crops cultivated in Northern Europe generally exhibited higher than current yields, as a consequence of wetter conditions, and temperatures closer to the optimum growing conditions. Simple, no-cost adaptation options such as advancement of sowing dates or the use of longer cycle varieties may be implemented to tackle the expected yield loss in southern Europe as well as to exploit possible advantages in northern regions.     

Sexual behavior,cannibalism, and mating plugs as sticky traps in the orb weaver spider <Emphasis Type="BoldItalic">Leucauge argyra</Emphasis> (Tetragnathidae)

Unpublished field observations in Leucauge argyra, a tropical orb weaver spider, suggest the occurrence of conspicuous mating plugs that could reduce or prevent remating attempts. Otherwise, the sexual behavior of this species remains unknown. The aims of this study were to describe the courtship behavior and copulation in L. argyra and investigate mating plug formation in this species. Fourteen virgin females and 12 plugged females were exposed to up to three males and checked for mating plug formation. Of the 12 virgins that copulated, nine produced plugs (five immediately after copulation), and the five plugged females that copulated produced another mating plug immediately after copulation. We did not detect the transfer of any male substance during copulation but observed a whitish liquid emerging from female genital ducts. Plug formation was positively associated with male twanging during courtship. One virgin and four plugged females cannibalized males. In seven trials with virgins and in three trials with plugged females, the male’s palp adhered to a substance that emerged from female genital ducts and spread on her genital plate. The male had to struggle energetically to free his glued palp; two of these males were cannibalized while trying to release their palps. Females seem to determine copulation duration by altering the timing of mating plug formation and through sexual cannibalism. This is the first case reported of a mating plug as a sticky trap for males.