Environmental monitoring by gene expression biomarkers in Barbus graellsii: laboratory and field studies

Barbel (Barbus graellsii) is a freshwater fish used as a sentinel species in environmental monitoring programmes and ecotoxicological studies in northern Spain, particularly in the Ebro River basin, the largest freshwater resource in Spain. We developed specific primers for the quantification of CYP1A and metallothionein (MT)-1 and -2 gene expression by QRT-PCR in barbel in order to assess their suitability in biological effect monitoring of dioxin-like compounds and metals. All three genes responded as expected in laboratory tests, using model inducers. Hepatic CYP1A mRNA levels showed a twofold induction in fish injected intraperitoneally with beta-naphthoflavone, whereas MT-1 and MT-2 gene expression was strongly induced by cadmium (15- and 13-fold, respectively) and mercury (five- and eightfold). Barbel populations from different sites on the Ebro River basin showed a good correlation between the historical records of organochlorine pollution, CYP1A expression levels and EROD activity. Nevertheless, although metallothionein protein levels in the liver of wild fish correlated with hepatic levels of mercury, MT-1 and MT-2 gene expression did not correlate with the mercury content or with the concentration of metals in sediments from the sites inhabited by the fish. These results demonstrate the utility of barbel CYP1A-mRNA expression, but not that of MT-1 or MT-2, as a biomarker in field studies. The tools and protocols developed here are likely to apply to other species of the genus Barbus, with some 700 species distributed throughout most of the Old World.     

We're all in this together…except for you: The effects of workload,performance feedback,and racial distance on helping behavior in teams

We draw from social categorization theory and the actor–observer hypothesis to extend previous research regarding receiving high levels of help from team members. Specifically, we explore how a team member's performance feedback on how they handled a disproportionately heavy share of the team's workload and how their racial distance from the rest of their teammates affect the amount of helping that person receives from their teammates. Results from a laboratory study in which 79 teams worked on a computerized, decision‐making task demonstrated a three‐way interaction between workload, performance feedback, and the racial distance between the feedback recipient and the rest of their teammates. Racially distant negative feedback recipients who had a disproportionately heavy share of their team's workload received less help from teammates than their racially similar counterparts. Copyright © 2012 John Wiley & Sons, Ltd.     

Modelling affected regions by the Iberian Quercus disease with proximity diagrams

Environmental Science and Pollution Research - In this work, we propose a mathematical model to determine the potential propagation areas of the Mediterranean Quercus disease commonly referred to...     

Sorption–desorption of indaziflam and its three metabolites in sandy soils

Indaziflam is a relatively new herbicide for which sorption–desorption information is lacking, and nothing is available on its metabolites. Information is needed on the multiple soil and pesticide characteristics known to influence these processes. For four soils, the order of sorption was indaziflam (N-[1R,2S)-2,3-dihydro-2,6-dimethyl-1H-inden-1-yl]-6-[(1R)-1-fluoroethyl]-1,3,5-triazine-2,4-diamine) (sandy clay loam: K_f = 5.9, 1/n_f = 0.7, K_foc = 447; sandy loam: K_f = 3.9, 1/n_f = 0.9, K_foc = 276) > triazine indanone metabolite (N-[(1R,2S)-2,3-dihydro-2,6-dimethyl-3-oxo-1H-inden-1-yl]-6-[(1R)-1-fluoroethyl]-1,3,5-triazine-2,4-diamine) (sandy clay loam: K_f = 2.1, 1/n_f = 0.8, K_foc = 177; sandy loam: K_f = 1.7, 1/n_f = 0.9, K_foc = 118) > fluoroethyldiaminotriazine metabolite (6-[(1R-1-Fluoroethyl]-1,3,5-triazine-2,4-diamine) (sandy clay loam: K_f = 0.3, 1/n_f = 0.9, K_foc = 28; sandy loam: K_f = 0.3, 1/n_f = 0.9, K_foc = 22) = indaziflam carboxylic acid metabolite (2S,3R)-3-[[4-amino-6-[(1R)-1-fluoroethyl]-1,3,5-triazin-2-yl]amino]-2,3-dihydro-2-methyl-1H-indene-5-carboxylic acid) (sandy clay loam: K_f = 0.3, 1/n_f = 0.9, K_foc = 22; sandy loam: K_f = 0.5, 1/n_f = 0.8, K_foc = 32). The metabolites being more polar than the parent compound showed lower sorption. Desorption was hysteretic for indaziflam and triazine indanone metabolite, but not for the other two metabolites. Unsaturated transient flow K_d's were lower than batch K_d's for indaziflam, but similar for fluoroethyldiaminotriazine metabolite. Batch K_d's would overpredict potential offsite transport if desorption hysteresis is not taken into account.     

IMPACTS OF URBANIZATION ON NUTRIENT CONCENTRATIONS IN SMALL SOUTHEASTERN COASTAL STREAMS1

ABSTRACT: Coastal watersheds in the southeastern United States are rapidly changing due to population growth and attendant increases in residential development, industry, and tourism related commerce. This research examined spatial and temporal patterns of nutrient concentrations in streams from 10 small watersheds (< 4 km²) that drain into Murrells Inlet (impacted) and North Inlet (pristine), two high salinity estuaries along the South Carolina coast. Monthly grab samples were collected during baseflow during 1999 and analyzed for total and dissolved inorganic and organic forms of nitrogen and phosphorus. Data were grouped into forested wetland creeks (representing predevelopment reference sites), urban creeks, and urban ponds. DON and NH4 concentrations were greater in forested streams than in urban streams. NO3 and TP concentrations were greatest in urban streams. Seasonally, concentrations were highest during summer for TN, NH4, DON, and TP, while NO3 concentrations were greatest during winter. Nutrient ratios clearly highlighted the reduction in organic nitrogen due to coastal development. Multiple regression models to predict instream nutrient concentrations from land use in Murrells Inlet suggest that effects are not significant (small r²). The findings indicate that broad land use/land cover classes cannot be used to predict nutrient concentrations in streams in the very small watersheds in our study areas.     

Carbamazepine and diclofenac: removal in wastewater treatment plants and occurrence in water bodies

In the aquatic environment, pharmaceuticals have been widely found. Among them, carbamazepine and diclofenac were detected at the highest frequency. To evaluate the worldwide environmental impacts of both drugs, their global consumption volumes are estimated, based on the dose per capita. The metabolites of these pharmaceuticals are also of environmental concerns, especially trans-10,11-dihydro-10,11- dihydroxycarbamazepine (CBZ-diol) which probably has a similar concentration in water bodies to that of its parent drug. The removal efficiencies and mechanisms of both drugs in the wastewater treatment plants (WWTPs) are discussed with the actual state of knowledge. The occurrences of both drugs are examined in various water bodies including WWTP effluents, surface waters, groundwater and drinking water. Their chemical, physical and pharmacological properties are also addressed in context, which can largely influence their environmental behaviors. The ecotoxicological studies of both drugs imply that they do not easily cause acute toxic effects at their environmental concentrations. However their chronic effects need cautious attention.     

Factors affecting CO<Subscript>2</Subscript> efflux rates and the stability of soil organic carbon storage in volcanic soils of the Canary Islands

Because volcanic soils store large amounts of soil organic carbon (SOC), they play a far more important role in the carbon (C) cycle than their limited global coverage suggests. We analysed the C released as CO₂ from a range of volcanic soils under natural conditions and analysed the influence of environmental variables (moisture and temperature), substrate availability (as assessed from the contents of various SOC fractions and the inputs of plant residues from litterfall), respiratory agents (roots, microorganisms and decomposing enzymes) and other pedological features of the topsoils (0–30 cm depth) on the CO₂ efflux rates over a 2-year experimental period. High CO₂ efflux rates (419 g C-CO₂ m^?2 y^?1 as the average for Andisols) were obtained that were related to significant decreases in the amount of SOC stored. CO₂ release was strongly controlled by soil moisture, although it was inhibited in the Andisols with the highest moisture levels (above 50 kg m^?2 in topsoil). It was not responsive to the availability of decomposing microorganisms or enzymes and appeared more related to the inputs of easily decomposable plant residues than to the amount of either labile or recalcitrant SOC. Among the SOC pools, only the water-soluble C in saturated paste extracts (WSC_se) of air-dried soil samples was consistently correlated with the CO₂ efflux rates. The desiccation of Andisols appeared to induce the release of previously stabilised SOC, which was readily mineralised when the moisture conditions became favourable. The results of this study indicate that SOC storage in Andisols is highly vulnerable to drying-wetting processes even in unmanaged natural ecosystems and that microclimate conditions can be critical for successful C sequestration in these soils.     

Genealogical Analysis of a Closed Herd of Black Hairless Iberian Pigs

Abstract: Livestock breeds are recognized as important components of world biodiversity. The Iberian pig is a swine breed well adapted to the Mediterranean forest ecosystem and provides cured products of high quality. The ancient population of Iberian pigs (  Sus scrofa meridionalis ) was differentiated in several local types, the black hairless pigs representing the fattest genetic type. The conservation program of the Guadyerbas strain has maintained this germplasm isolated since 1945 as a closed population in an experimental herd. The complete pedigree, with 1000 breeding animals descending from 24 founders, has been used to measure along the successive cohorts of breeding animals the effective number of founders, effective number of nonfounders, founder genome equivalents, and expected number of founders' surviving alleles. For the last cohort, the values were 10.34, 1.42, 1.25, and 4.06, respectively. The evolution of inbreeding and coancestry and its components attributable to each founder were also studied. The rate of increase in inbreeding and coancestry was 2.21% per cohort, or 0.906% per year. Finally, the effect of family structure and mating tactics on the evolution of coancestry was also analyzed. The greatest rates of coancestry per cohort were attributable to unbalanced family sizes, and the use of minimum coancestry matings effectively delayed the increase in inbreeding.