Bioavailability and biodegradation of prosulfocarb in soil

Active microbial degraders of the herbicide prosulfocarb (PSC) were isolated to evaluate their performance in soil with a view to their use for bioremediation. The isolated cultures (a microbial consortium and a Pseudomonas sp. strain) were active when tested in mineral medium with PSC as the only carbon source, but had an adverse effect on the soil indigenous microflora. Biodegradation in the inoculated soils was thus lower than in the uninoculated soil when only the indigenous microflora was present. Further tests showed that the strong affinity of PSC for soil organic matter affected its bioavailability and hence its biodegradation by the inocula. Bioremediation of PSC contaminated soils could thus be undertaken by biostimulation of indigenous microflora.     

Radium-226 in cattails, Typha latifolia, and bone of muskrat, Ondatra zibethica (L.), from a watershed with uranium tailings near the city of Elliot Lake, Canada

Radium-226 concentrations were measured in the main food plants (cattails, Typha latifolia) and bone of adult muskrats (Ondatra zibethica (L.)), taken from a study area near Quirke Lake in the Serpent River drainage basin. This watershed receives drainage containing radionuclides from the U tailings near the City of Elliot Lake, Ontario, Canada. Two control sites (one local, one 130 km distant) were also sampled. Radium-226 levels in cattails varied by plant part and place of collection. Roots sampled in the study area had the highest mean (226)Ra level (1135.0 mBq g(-1)), stems and leaves had 284.2 and 275.9 mBq g(-1), respectively (dry-weight basis, n = 6 in all cases). Local and distant control cattails carried much lower (226)Ra levels (20.2 and 15.2 mBq g(-1) dry weight, respectively, using pooled equal portions of all plant parts, n = 3 in both cases). Muskrats from waters with mean total (226)Ra levels in the period, 1984-1987 greater than 75.0 mBq litre(-1) ('study-high' sites), near U tailings within 10 km of Quirke Lake, had a mean (geometric) bone level of (226)Ra of 344.9 mBq g(-1) (dry-weight basis, n = 36); those from nearby waters, containing < 75.0 mBq litre(-1) of (226)Ra ('study-low' sites), had a mean bone level (80.3 mBq g(-1), n = 9) similar to animals taken in unaffected local control areas 20 km from the tailings (79.1 mBq g(-1), n = 12); animals from the distant control area, near Sudbury, Ontario, had the lowest mean burden (11.5 mBq g(-1), n = 24). Levels were unrelated to age or sex of the animals. Dry-weight based (226)Ra concentration ratios (bone concentration/plant tissue concentration) were calculated to range from 0.3-1.4 in the study-high area to 2.4-6.3 in the local control area. Wet-weight based concentration ratios were about 4.3 times higher. Concentration ratios were similar to values calculated for other species and in general agreement with values calculated for humans. The muskrat is judged to be a useful indicator (biomonitor) of environmental (226)Ra levels as there is a highly significant positive correlation coefficient (r = 0.74) between bone and ambient (water) concentrations of the radionuclide (F79 = 95.04, P < 0.0001) Estimated yearly (226)Ra intake by people eating muskrats was calculated to be below the current allowable level set by Canadian regulatory authorities.     

Temperature dependence of Henry's law constants of metolachlor and diazinon

A dynamic system based on the water/air equilibrium at the interface within the length of a microporous tube has been used to determine experimentally the Henry's law constants (HLC) of two pesticides: metolachlor and diazinon. The measurements were conducted over the temperature range 283-301 K. At 293 K, HLCs values are (42.6+/-2.8) x 10(3) (in units of M atm(-1)) for metolachlor and (3.0+/-0.3)x10(3) for diazinon. The obtained data were used to derive the following Arrhenius expressions: HLC=(3.0+/-0.4) x 10(-11) exp((10,200+/-1,000)/T) for metolachlor and (7.2+/-0.5) x 10(-15) exp((11,900+/-700)/T) for diazinon. At a cumulus cloud temperature of 283 K, the fractions of metolachlor and diazinon in the atmospheric aqueous phase are about 57% and 11% respectively. In order to evaluate the impact of a cloud on the atmospheric chemistry of both studied pesticides, we compare also their atmospheric lifetimes under clear sky (tau(gas)), and cloudy conditions (tau(multiphase)). The calculated multiphase lifetimes (in units of hours) are significantly lower than those in gas phase at a cumulus temperature of 283 K (in parentheses): metolachlor, 0.4 (2.9); diazinon, 1.9 (5.0).     

Degradation of chlorobenzenes by a strain of Acidovorax avenae isolated from a polluted aquifer

A subsurface microbial community was isolated from a polluted site of Suquía River (Córdoba-Argentina), acclimated during 15 days in aerobic conditions using 1,2-dichlorobenzene (1,2-DCB) as the sole carbon source. From this acclimated community, we isolated and identified by 16S rDNA analysis a strain of Acidovorax avenae, which was able to perform the complete biodegradation of 1,2-DCB in two days affording stoichiometric amounts of chloride. This pure strain was also tested for biodegradation of chlorobenzene (CB); 1,3-DCB and 1,4-DCB, giving similar results to the experiments using 1,2-DCB. The aromatic-ring-hydroxylating dioxygenase (ARHDO) alpha-subunit gene core, encoding the catalytic site of the large subunit of chlorobenzene dioxygenase, was detected by PCR amplification and confirmed by DNA sequencing. These results suggest that the isolated strain of A. avenae could use a catabolic pathway, via ARHDO system, leading to the formation of chlorocatecols during the first steps of biodegradation, with further chloride release and subsequent paths that showed complete substrate consumption.     

Effects of environmental parameters on the chestnut gall wasp and its complex of indigenous parasitoids

The chestnut gall wasp (CGW), Dryocosmus kuriphilus, an invasive pest native to China, has caused severe yield and economic losses to chestnut production in Europe since its arrival in 2002. In Southern Italy, the complex of indigenous parasitoids colonizing CGW was monitored between 2013 and 2015, with the aim of estimating the composition of the indigenous parasitoid complex, its ability to control CGW populations, and the interactions of both factors with several measured environmental parameters. We compared results among three differently managed field types. Results showed an increase in the rate of parasitism both when the host population density was lower and in unmanaged chestnut stands with more natural conditions. The percentage of parasitism in galls was related to morphological traits of the galls and to higher seasonal temperatures, which reduced the parasitism intensity because CGW develops earlier under such conditions. The host–parasitoid mortality inside galls varied among sites and was associated mostly with rot fungi during wet spring and summer months. Parasitoid species richness was similar among the study sites, but the proportion of parasitoid species differed between orchards and unmanaged coppice stands. The timing of attack by parasitoids followed a species-specific successional sequence throughout the larva-to-adult life cycle of the CGW. These interactions should be considered in future research on trophic relationships and when modeling invasive scenarios for new pest species.     

The determinants mostly disclosed by companies that are members of the Carbon Disclosure Project

Concerns about climate change as a result of anthropic actions have led to an increase in the volume of information disclosed about it in the reports of companies that are members of the Carbon Disclosure Project (CDP). In this context, the factors most disclosed remain obscure due to both the complexity of climate change impacts and the stakeholders’ different interests. This study aims to identify which factors are most disclosed in the reports of companies that are members of CDP. For this purpose, it is necessary to investigate if the factors indicated by managers and experts are the main ones disclosed in the reports of Brazilian companies that are members of CDP, as well as to identify which companies stand out in climate change disclosure based on these factors. To this end, 463 reports submitted by 48 companies between 2014 and 2016 were examined and 32 factors were investigated using the NVivo® software. Some companies submitted reports with unified titles, which reduced the sample. The results indicate that certain factors—prevention of pollution, prevention of loss, management of environmental assets, volume of greenhouse gas (GHG) emissions, and climate change strategy—account for 50.03% of the total volume of information disclosed about climate change. The main lesson learned from this research is that climate change mitigation strategy is strongly supported by the evidence of corporate annual reports, and it has relation with the following determinant factors: pollution prevention, loss prevention, environmental asset management, GHG emissions, and the strategy chosen by the companies to deal with climate change. Due to the low volume of research related to loss prevention and pollution prevention, we have identified that little attention has been paid to these items. Based on our results, we recommend that climate change mitigation strategies begin to consider these determinant factors in their structure because both have a strong influence in demonstrating how companies are managing these factors for stakeholders. Therefore, companies can benefit from this data to manage their resources for the maintenance of the social contract (legitimacy) through the factors most disclosed, especially companies with lower scores on the scale of ranking presented. Hence, stakeholders can have access to more information on strategies that mitigate climate change and help companies improve the disclosure of the actions that contribute to reduction of GHG emissions.     

Headwater streams: neglected ecosystems in the EU Water Framework Directive. Implications for nitrogen pollution control

The European Union Water Framework Directive (WFD) aims to achieve the “good status” of waters by 2015, through monitoring and control of human impacts on “bodies of surface water” (BSWs), discrete elements for quality diagnosis and management. Headwater streams, however, are frequently neglected as they are not usually recognised as BSW. This poses limitations for the management of river catchments, because anthropogenic impacts on headwaters can constrain the quality of downstream rivers. To illustrate this problem, we compared nitrate levels and land use pressures in a small agricultural catchment with those recorded in the catchment in which it is embedded (Ega), and in the Ebro River Basin (NE Spain) comprising both. Agriculture greatly influenced water nitrate concentration, regardless of the size of the catchments: R² = 0.91 for headwater catchments (0.1–7.3 km²), and R² = 0.82 for Ebro tributary catchments (223–3113 km²). Moreover, nitrate concentration in the outlet of a non-BSW small river catchment was similar to that of the greater downstream BSW rivers. These results are of interest since, despite representing 76% of the length of the Ega catchment hydrographical network, only 3.1% of the length of the headwater streams has been identified as BSWs. Human activities affecting headwater streams should therefore be considered if the 2015 objective of the WFD is to be achieved.     

Efficiency of white lupin in the removal of mercury from contaminated soils： Soil and hydroponic experiments

This study examined the ability of the white lupin to remove mercury (Hg) from a hydroponic system (Hg concentrations 0, 1.25, 2.5, 5 and 10 μmol/L) and from soil in pots and lysimeters (total Hg concentration (19.2 ± 1.9) mg/kg availability 0.07%, and (28.9 ± 0.4) mg/kg availability 0.09%, respectively), and investigated the accumulation and distribution of Hg in different parts of the plant. White lupin roots efficiently took up Hg, but its translocation to the harvestable parts of the plant was low. The Hg concentration in the seeds posed no risk to human health according to the recommendations of the World Health Organization, but the shoots should not be used as fodder for livestock, at least when unmixed with other fodder crops. The accumulation of Hg in the hydroponically-grown plants was linear over the concentration range tested. The amount of Hg retained in the roots, relative to the shoots, was almost constant irrespective of Hg dose (90%). In the soil experiments, Hg accumulation increased with exposure time and was the greater in the lysimeter than in the pot experiments. Although Hg removal was the greater in the hydroponic system, revealing the potential of the white lupin to extract Hg, bioaccumulation was the greatest in the lysimeter-grown plants; the latter system more likely reflects the true behaviour of white lupin in the field when Hg availability is a factor that limits Hg removal. The present results suggest that the white lupin could be used in long-term soil reclamation strategies that include the goal of profitable land use in Hg-polluted areas.     

Linking Russia with the European and global greenhouse gas emissions trading markets: three paths for greening the Russian assigned amount under the Kyoto Protocol

This article examines possibilities for linkage between the European Union Emissions Trading System (EU ETS) and Russia, with a view to enhancing cooperation on a broader scale than the project-based approaches that have been tested thus far. Three paths for possible EU-Russia linkage are presented by which the Russian Assigned Amount under the Kyoto Protocol can be greened in order to stimulate emissions trading: 1. Joint implementation—reductions earned via individual projects in Russia; 2. Greened allowances or green investment schemes; and 3. Linked cap-and-trade systems, in which a Russian domestic emissions trading system would link with the European Union Emissions Trading System. The authors conclude that the third option, emissions trading through linked domestic emissions trading systems, offers the best opportunities at the lowest transaction costs. The authors discuss useful innovative instruments like call options and slip level arrangements on government-to-government and business-to-business levels.