Sorption behavior of a new acidic herbicide in soils

The sorptive behavior of the experimental herbicide quinmerac (7-chloro-3-methyl-quinoline-8-carboxylic acid) was investigated in soils of different organic carbon content. Distribution coefficients are low (K_d = 0.03 - 12 mL g⁻¹) and are mainly determined by the soil organic carbon content. The adsorption mechanism operating in neutral to slightly acid agricultural soils is supposed to be cation bridging with the anionic form of quinmerac. Under acid conditions (pH 5.2) the predominating sorption mechanism is hydrophobic interaction. Therefore soil pH and cationic composition are also major factors determining the sorptive capacity of soils for quinmerac.

Adsorption kinetics, equilibrium adsorption and desorption isotherms were determined in batch experiments. Sorption kinetics were investigated at various times from 15 min to 96 hours. A two-step sorption behavior with time was found for the anionic form indicating two types of sorption mechanisms or sorption sites. Equilibrium for the first type was reached at a time-scale of minutes and for the second type after 24 hours. Adsorption isotherms were determined for two soil/solution ratios 1/5 and 1/3. Alteration of the adsorbent concentration exerted a strong influence on the adsorption isotherms. An increase of sorption was found with increasing adsorbent concentration. Under natural soil conditions sorption is therefore expected to be higher compared to the batch experiments. Desorption isotherms were obtained using the consecutive desorption method. Desorption hysteresis was not observed which indicates weak interactions. Implications of the results for the movement of quinmerac under field conditions and for models describing transport are discussed.     

The use of the ecological footprint in local politics and administration: results and implications from Norway

Our experiences calculating a local ecological footprint of Oslo form the basis for a discussion of key methodological aspects supporting the use of local sustainability indicators. The footprint's strength is its ability to communicate simply the complexity of global environmental challenges. Initially developed for measuring per capita consumption at the national level, the footprint has been adopted at local and regional levels. We argue for adjustments in the footprint methodology when shifting from a national to a local policy context, to ensure the indicator's applicability in local politics and administration. First, the analysis should be limited to consumption aspects relevant to the local environmental policy agenda. Second, the analysis should integrate as much genuine local data as possible. We argue also that a standardised methodology based on the national footprint approach, with the main purpose of international benchmarking of cities, cannot but reduce the indicator's usefulness for administrative/political guidance, due to the methodology's lack of transparency and inability to identify local variations.     

False-positive diagnosis of trisomy 21 using fluorescence in situ hybridisation (FISH) on uncultured amniotic fluid cells

An amniocentesis was performed on a 22-week pregnancy following the detection of foetal abnormalities on ultrasound. A rapid aneuploid screen using fluorescence in situ hybridisation on uncultured amniotic fluid cells revealed 3 signals for chromosome 21, consistent with trisomy 21. In situ metaphase cultures revealed a 46,XY normal male karyotype. These discordant results may be explained by a sub-standard batch of the commercially available probe or alternatively, a very specific variation within the sample interacting with the probe. Alternative strategies are proposed in order to safeguard against inappropriate clinical action as a consequence of discordant results. Copyright © 2003 John Wiley & Sons, Ltd.     

Recovering from disasters: a study of livelihoods in post‐quake villages in northern Pakistan

The October 2005 earthquake in northern Pakistan severely affected the livelihoods of 1.5 million people. With the destruction of material assets and communications infrastructure, the quake had a devastating impact on people's way of life in this remote mountainous region. This paper explores livelihood revival interventions undertaken during the earthquake response, and considers how differentiated livelihood outcomes were achieved. In addressing this objective the paper examines livelihood rehabilitation schemes in terms of structural aspects, working strategies, key factors, strengths of interventions and the role of human agency in influencing livelihood trajectories of quake‐affected communities. Primary data for this study was gathered in northern Pakistan between October 2008 and January 2009. The study identifies structural shortcomings and strengths of the programmes attempting to revive the livelihoods of poor and vulnerable households. It identifies how households in two villages made the most of opportunities to improve their lives and move towards favourable outcomes.     

Bioconcentration of zinc and cadmium in ectomycorrhizal fungi and associated aspen trees as affected by level of pollution

Concentrations of Zn and Cd were measured in fruitbodies of ectomycorrhizal (ECM) fungi and leaves of co-occurring accumulator aspen. Samples were taken on three metal-polluted sites and one control site. Fungal bioconcentration factors (BCF = fruitbody concentration: soil concentration) were calculated on the basis of total metal concentrations in surface soil horizons (BCF_tot) and NH₄NO₃-extractable metal concentrations in mineral soil (BCF_lab). When plotted on log-log scale, values of BCF decreased linearly with increasing soil metal concentrations. BCF_lab for both Zn and Cd described the data more closely than BCF_tot. Fungal genera differed in ZnBCF but not in CdBCF. The information on differences between fungi with respect to their predominant occurrence in different soil horizons did not improve relations of BCF with soil metal concentrations. Aspen trees accumulated Zn and Cd to similar concentrations as the ECM fungi. Apparently, the fungi did not act as an effective barrier against aspen metal uptake by retaining the metals.     

Assessment of a reclamation cover system for phosphogypsum stacks in Central Alberta, Canada

Phosphogypsum (PG), a byproduct of the phosphate fertilizer industry, was produced and stockpiled at the Agrium Fort Saskatchewan facility from 1965 to 1991. Upon decommissioning, the outer slopes of the PG stacks were reclaimed by applying 15 cm of topsoil and planting a non-native seed mix. Physical, chemical, and hydrologic evaluations of the cover system confirmed that plants were successfully growing in various soil capping depths and were often rooting more than 200 mm into the PG. Percolation past the substrate into PG during a typical storm event was low (< 10 mm), and runoff from the stacks was negligible. Runoff quality met most guidelines, but some parameters, including fluoride, were up to 18 times higher than provincial or federal guidelines for soil and water quality. However, the cover system, when applied appropriately, does meet basic reclamation objectives. The exceedances are found in areas where the cover system has been compromised by erosion or mixing or in areas where the cover system has not been fully applied, such as roads or the inner basin. In areas where the cover system has been applied successfully, basic reclamation requirements are met.     

Seasonal variation of pollution biomarkers to assess the impact on the health status of juvenile Pacific oysters <Emphasis Type="BoldItalic">Crassostrea gigas</Emphasis> exposed in situ

Background, aim, and scope  

In this study, a suite of sublethal stress biomarkers were analyzed in juveniles of the sentinel species, the Pacific oyster Crassostrea gigas, with a view to using them as pollution monitoring tools. The aim of this work was (1) to study baseline seasonal variations of biomarkers in different body compartments of C. gigas in the reference site and, after selecting biomarkers presenting no seasonal variations, (2) to compare responses of these biomarkers between contaminated and reference sites.     

Monitoring atmospheric pollutants in the biosphere reserve Wienerwald by a combined approach of biomonitoring methods and technical measurements

In this study a combined approach of bioindication results correlated with an extensive set of data on air pollution and climate was used to assess the pollution status of the Man and Biosphere Reserve Wienerwald (Austria). Bryophytes served as impact indicators (via the Index of Atmospheric Purity-method IAP) at 30 sites as well as accumulation monitors for airborne trace elements (Al, Pb, V, S, Zn, Fe, Cu, Cr, Ni, Co, Mo, Cd, As, Sb and 16 EPA-PAHs) at 10 sites within the reserve. The results of these bioindication methods were subsequently correlated with further pollution (NO(2), SO(2) and dust) and climate data (precipitation, temperature and humidity). The findings obtained clearly indicate the following: Bryophyte distribution is solely influenced by the status of air quality, without interference by climatic or site-related factors, which is in contrast to several previous investigations. IAP-values correlated significantly with NO(2) (0.553; P=0.004), SO(2) winter values (0.511; P=0.013) and PM10 (dust) (0.561; P=0.013). The results obtained via chemical analyses revealed a strong correlation with data derived from the IAP methodology. In terms of the overall air quality within the biosphere reserve Wienerwald, the north-eastern part appears to be the most affected one with a most likely pollution contribution emitted by the capital city Vienna, agriculture and neighbouring countries.