Responses of spring wheat (Triticum aestivum L.) to ozone produced by either electric discharge and dry air or by UV-lamps and ambient air

The aim of the present study was to examine if ozone produced similar effects on spring wheat growth with and without small amounts of nitrogen oxides. Two methods were used to produce ozone: the first method consisted of dry pressurized air fed to an electric discharge generator generating the byproducts, N2O5 and N2O, the second method consisted of ambient air fed to UV-lamps. Two spring wheat cultivars (Triticum aestivum L. cvs Minaret and Eridano) were exposed in small open-top chambers to charcoal-filtered air, non-filtered ambient air, and non-filtered ambient air with the addition of ozone for 8 h (0900 to 1700 h) daily, for five weeks. Plants were harvested every week. The growth of Minaret was shown to be more sensitive to O3 than that of Eridano. Leaf senescence increased with increasing ozone level in both cultivars. The total above-ground biomass dry weight decreased with increasing ozone concentration in Minaret, but not in Eridano. The Minaret plants reacted with more damaged leaf dry weight and inhibition of growth when O3 was produced by UV-lamps than when O3 was produced by air fed to an electric discharge generator. This could be explained by more nitrogen content per plant but not by increased nitrogen concentration in plant tissue in plants exposed to increased O3 and small amounts of incidental nitrogen oxides.     

Surfactant solubilization of hydrophobic compounds in soil and water

The soil/water partition coefficient (K_d) of hexachlorobenzene (HCB) ranged from 220 1/kg to 1800 1/kg for eight soils having a wide range of physico-chemical properties. K_d normalised to soil organic carbon (K_oc) was found to be 28000 ± 4800 1/kg. Anionic surfactant dodecylsulphate (DS) present at concentrations above the critical micellar concentration (CMC) caused reductions in the apparent soil/water partition coefficient (K_d ^*) in the range of 3–26 times for most soils and up to 36–91 times for sandy soils. Below CMC, at environmentally relevant surfactant concentrations, K_d ^* was reduced by a factor of 1–13. For clay and calcareous soils significant adsorption/complexation/precipitation of DS occurred. At the lowest DS concentration this produced a two-fold increase in K_d ^*. At increasing DS concentrations this effect was shielded by the solubihzing effect from DS. Monomer (K_mn) and micellar (K_mc) surfactant/water partition coefficients for HCB were determined to be, 980 ± 190 1/kg and 21000 ± 1600 1/kg, respectively.     

Chemical and biological characterization of emissions from a cereal straw burning furnace

Emissions from a cereal straw through-burning furnace have been characterized by chemical analysis and the Ames $\text{Salmonella/microsome}$ assay. The emissions of polycyclic aromatic hydrocarbons (PAH) were considerable, from 24 to 64 mg per kilo dry fuel. Most of the mutagenic activity was found in the extracts of the particles, while the condensate fractions and the XAD-2 extracts showed much lower mutagenic responses.     

Environmental risk assessment of human pharmaceuticals in Denmark after normal therapeutic use

An environmental risk assessment is presented for the 25 most used pharmaceuticals in the primary health sector in Denmark. Predicted environmental concentrations (PECs) for the aquatic environment were calculated using conservative assumptions and all PECs exceeded 1 ng/l. Measured concentrations were in general within a factor of 2-5 of PECs and ranged from approximately 0.5 ng/l to 3 micrograms/l for nine of the pharmaceuticals reported in literature. The calculation of predicted no-effect concentration (PNEC) based on aquatic ecotoxicity data was possible for six of the pharmaceuticals. PEC/PNEC ratio exceeded one for ibuprofen, acetylsalicylic acid, and paracetamol. For estrogens the PEC/PNEC ratio approached one when non-standard test was used. The ratio was below one for estrogens (standard test), diazepam and digoxin. For the terrestrial compartment, toxicity data were not available, and no assessment was carried out. Comparisons of predicted concentrations of furosemide, ibuprofen, oxytetracycline and ciprofloxacin in sludge based on either preliminary experimental sludge-water partition coefficients (Kd), octanol-water coefficients (Kow) or acid-base constants (pKa) revealed large variations.     

Synthesis of effects in four Arctic subregions

An assessment of impacts on Arctic terrestrial ecosystems has emphasized geographical variability in responses of species and ecosystems to environmental change. This variability is usually associated with north-south gradients in climate, biodiversity, vegetation zones, and ecosystem structure and function. It is clear, however, that significant east-west variability in environment, ecosystem structure and function, environmental history, and recent climate variability is also important. Some areas have cooled while others have become warmer. Also, east-west differences between geographical barriers of oceans, archipelagos and mountains have contributed significantly in the past to the ability of species and vegetation zones to relocate in response to climate changes, and they have created the isolation necessary for genetic differentiation of populations and biodiversity hot-spots to occur. These barriers will also affect the ability of species to relocate during projected future warming. To include this east-west variability and also to strike a balance between overgeneralization and overspecialization, the ACIA identified four major sub regions based on large-scale differences in weather and climate-shaping factors. Drawing on information, mostly model output that can be related to the four ACIA subregions, it is evident that geographical barriers to species re-location, particularly the distribution of landmasses and separation by seas, will affect the northwards shift in vegetation zones. The geographical constraints--or facilitation--of northward movement of vegetation zones will affect the future storage and release of carbon, and the exchange of energy and water between biosphere and atmosphere. In addition, differences in the ability of vegetation zones to re-locate will affect the biodiversity associated with each zone while the number of species threatened by climate change varies greatly between subregions with a significant hot-spot in Beringia. Overall, the subregional synthesis demonstrates the difficulty of generalizing projections of responses of ecosystem structure and function, species loss, and biospheric feedbacks to the climate system for the whole Arctic region and implies a need for a far greater understanding of the spatial variability in the responses of terrestrial arctic ecosystems to climate change.     

Major challenges of integrating agriculture into climate change mitigation policy frameworks

Taking the European Union (EU) as a case study, we simulate the application of non-uniform national mitigation targets to achieve a sectoral reduction in agricultural non-carbon dioxide (CO₂) greenhouse gas (GHG) emissions. Scenario results show substantial impacts on EU agricultural production, in particular, the livestock sector. Significant increases in imports and decreases in exports result in rather moderate domestic consumption impacts but induce production increases in non-EU countries that are associated with considerable emission leakage effects. The results underline four major challenges for the general integration of agriculture into national and global climate change mitigation policy frameworks and strategies, as they strengthen requests for (1) a targeted but flexible implementation of mitigation obligations at national and global level and (2) the need for a wider consideration of technological mitigation options. The results also indicate that a globally effective reduction in agricultural emissions requires (3) multilateral commitments for agriculture to limit emission leakage and may have to (4) consider options that tackle the reduction in GHG emissions from the consumption side.     

Lost benefits and carbon uptake by protection of Indian plantations

There is a range of problems in assessing how protection of a specific forest to Reduce Emissions from Deforestation and forest Degradation (REDD+) affect global emissions of greenhouse gases. This paper shows how knowledge and information about the biophysical characteristics of forests can be combined with theories of forest management and economic behaviour to derive the impacts on global emissions of REDD+. A modelling experiment from India, where 10% of the forest plantations in eight different regions are protected, shows that the biophysical characteristics of forests are decisive for the global impacts on emissions. In regions with slow-growing forests, agents in the non-protected forests are able to increase their output significantly to fill the demand from the protected forests. This opportunity is strictly limited in regions with fast-growing forests. Therefore, prices increase far more in regions with fast-growing forests than in slow-growing forests. Over time, the markets for Indian forestry products contribute to reduce the resulting price differences across regions. When the carbon uptake from protected forests approaches zero, the leakage of emissions to other Indian forests is between 20 and 40%. Only a small part of this is international leakage. Combining different models also helps to identify knowledge gaps, and to distinguish gaps that potentially may be filled with data and new knowledge, and gaps due to different angling of modelling biophysical processes and modelling of economic behaviour.     

Prevalence and concentrations of drugs in older suspected drugged drivers

Objective: Older drivers are somewhat more likely to be involved in car crashes than middle-aged drivers but less likely to be involved than younger drivers. This study aimed to assess the extent of drug use in older suspected drunk and drugged drivers, with respect to which drugs were detected and at which concentrations.

Methods: Blood samples from older suspected drunk and drugged drivers taken between February 1, 2012, and May 22, 2013, were identified from the database at the Norwegian Institute of Public Health and were retrospectively analyzed for a broad repertoire of drugs relevant for impairment. The prevalence of different drugs among the suspected drunk and drugged drivers was studied. Regarding drug concentrations, the findings in older drivers (>65 years) were compared to a reference group of apprehended drivers aged 20–40 years.

Results: Four hundred and ten older suspected drunk and drugged drivers were included. Any drug (including ethanol) was detected in 92% of blood samples, and ethanol was detected in 81%. Benzodiazepines were found in 15% of the older drivers and z-hypnotics (zopiclone or zolpidem) were detected in 13%. The most frequent single legal drugs found in blood samples taken from older impaired drivers were zopiclone (9.8%) and diazepam (9.3%). Regarding drug combinations, older drivers used a mean number of 1.4 drugs, and 20% of ethanol-positive cases showed at least one other drug. High drug concentrations of clonazepam and diazepam were more frequently seen in the younger group.

Conclusions: This study showed that drugs were detected in the vast majority of older drivers suspected for drunk or drugged driving. Ethanol was the most frequent drug detected, followed by zopiclone and diazepam. Older drivers combine drugs to a lesser degree than younger drivers, but their combination of ethanol and other drugs represents a considerable traffic risk. Lower concentrations of benzodiazepines are seen in older compared to younger drivers.