Lead concentrations in soil, sediment and clam samples from the Pungo River peatland area of North Carolina, USA

Lead (Pb) concentrations were measured in samples of peat soils, sediments and clams (Rangia cuneata) collected from the Pungo River region of coastal North Carolina. In peat soils, mean Pb concentrations (dry weight +/- 1 SD) were significantly higher (p<0.05) in surface samples (12.8microg g(-1)+/-7.6) than in samples from depths of 20 cm (2.7microg g(-1)+/-2.7) or 1 m (3.6microg g(-1)+/-3.6). Mean Pb concentrations in surface sediments from canals draining peatlands and from the Pungo River which receives this drainage ranged from 0.1microg g(-1)+/-0.1 to 7.0microg g(-1)+/-0.6. These Pb concentrations are similar to values reported in other studies for areas considered uncontaminated. Fractionation analysis revealed that the majority of the Pb in the peat and sediment samples was associated with the residual fraction, with lesser amounts in the organically-bound fraction, and generally negligible amounts in the water-soluble fraction. These results indicate that the bulk of the Pb in the soils and sediments of this area is relatively immobile and non-bioavailabe. This is supported by the relatively low concentrations of Pb (0.2-0.5 microg g(-1), dry weight) observed in soft tissues of R. cuneata collected from the Pungo River.     

Organochlorine pesticides and polychlorinated biphenyl residues in reared and wild Dicentrarchus labrax from the Mediterranean Sea (Sicily, Italy)

The aim of this research was to compare the levels of organochlorine pesticides and PCBs in samples of Dicentrarchus labrax living in the Straits of Messina with samples cultivated in cages in the Mediterranean Sea. Muscles and liver tissues sampled over the months, within the same year, were analyzed. The quantitative determination of the organochlorine compounds was performed by GC-ECD and confirmed with GC–MS. The results showed that the concentrations of DDTs in muscles and livers as such of reared sea bass were in the range 0.2–1.3 μg/kg and 9.6 –48.4 μg/kg, respectively. In wild fish the concentrations of DDTs were very much lower: 0.1 μg/kg in muscles, 5.1–9.0 μg/kg in livers. Total PCBs levels were higher in cultivated sea bass than in wild fish; the concentration ranges were 5.3–59.7 μg/kg and 74.4–267.4 μg/kg in muscle and liver of reared samples, respectively, and 1.1–1.5 μg/kg and 63.2–109.4 μg/kg in muscle and liver of wild samples, respectively.     

不同氮磷比对铜绿微囊藻及附生假单胞菌磷代谢的影响

以铜绿微囊藻及其附生假单胞菌X菌株为研究对象,研究了不同氮磷比对铜绿微囊藻和假单胞菌之间磷代谢的影响.结果发现,无论有无附生菌存在,铜绿微囊藻在氮磷比为16：1时,生长情况最好,此时微囊藻能迅速有效地吸收水中的磷,而且附生菌的存在能促进藻的生长.而在氮磷比为4：1时,藻的生长情况最差,在实验后期,藻细胞死亡分解后把一些含磷化合物释放到了水中,附生菌的存在能够加速藻细胞的衰亡和藻体内磷的释放.     

环境中短链和中链氯化石蜡的来源、污染特征及环境行为研究进展

短链氯化石蜡(SCCPs)是持久性有机污染物,已于2017年5月被正式列入《关于持久性有机污染物的斯德哥尔摩公约》附件A的受控名单.中链氯化石蜡(MCCPs)具有相似的性质.由于氯化石蜡(CPs)大量生产以及广泛应用,其在环境介质中的含量处于较高水平.本文综述了 SCCPs和MCCPs的生产和排放,以及2016年以后文...     

Paternity alone does not predict long-term investment in juveniles by male baboons

Adult male chacma baboons (Papio hamadryas ursinus) form preferential associations, or friendships, with particular lactating females. Males exhibit high levels of affiliative contact with their friends’ infants and defend them from potentially infanticidal attacks (Palombit et al. 1997). Little is known about males’ associations with juveniles once they have passed the period of infanticidal risk. We conducted an observational, experimental, and genetic study of adult male and juvenile chacma baboons in the Moremi Reserve, Botswana. We identified preferential associations between males and juveniles and used behavioral data and a playback experiment to explore whether those associations have potential fitness benefits for juveniles. We determined whether males preferentially invest in care of their own offspring. We also determined how often males invest in care of their former friends’ offspring. The majority of juveniles exhibited preferential associations with one or two males, who had almost always been their mother’s friend during infancy. However, in only a subset of these relationships was the male the actual father, in part because many fathers died or disappeared before their offspring were weaned. Male caretakers intervened on behalf of their juvenile associates in social conflicts more often than they intervened on behalf of unconnected juveniles, and they did not appear to differentiate between genetic offspring and unrelated associates. Playbacks of juveniles’ distress calls elicited a stronger response from their caretakers than from control males. Chacma males may provide care to unrelated offspring of former friends because the costs associated with such care are low compared with the potentially high fitness costs of refusing aid to a juvenile who is a possible offspring.     

正态信息扩散法在确定河冰抗压强度概率分布中的应用

将正态信息扩散法应用于小样本条件下河冰抗压强度概率密度函数的确定,建立了小样本条件下河冰抗压强度概率分布,并结合K-S检验法和河冰抗压强度试验数据,分析了该方法的合理性。结果表明,本文方法可以较好解决小样本情况下河冰抗压强度概率分布的确定问题,正态信息扩散分布更加接近河冰抗压强度的真实分布,并优于经典分布的拟合方法。     

May a comprehensive mineralogical study of a jackstone calculus and some other human bladder stones unveil health and environmental implications?

This paper represents the first result of an active collaboration between the University of Sannio and the San Pio Hospital (Benevento, Italy), started in the 2018, that aims to a detailed mineralogical investigation of urinary stones of patients from Campania region. Herein, selected human bladder stones have been deeply characterized for clinical purposes and environmental biomonitoring, focusing on the importance to evaluate the concentration and distribution of undesired trace elements by means of microscopic techniques in the place of conventional wet chemical analyses. A rare bladder stone with a sea-urchin appearance, known as jackstone calculus, were also investigated (along with bladder stones made of uric acid and brushite) by means a comprehensive analytical approach, including Synchrotron X-ray Diffraction and Simultaneous Thermal Analyses. Main clinical assumptions were inferred according to the morpho-constitutional classification of bladder stones and information about patient’s medical history and lifestyle. In most of the analyzed uroliths, undesired trace elements such as copper, cadmium, lead, chromium, mercury and arsenic have been detected and generally attributable to environmental pollution or contaminated food. Simultaneous occurrence of selenium and mercury should denote a methylmercury detoxification process, probably leading to the formation of a very rare HgSe compound known as tiemannite.

     

Adsorption of herring sperm DNA onto pine sawdust biochar: Thermodynamics and site energy distribution

● Adsorption of environmental deoxyribonucleic acid on biochar was studied. ● π−π interaction and electrostatic repulsion worked in the adsorption. ● Thermodynamics indicated the adsorption was spontaneous and endothermic. Environmental deoxyribonucleic acid (eDNA), which includes antibiotic resistance genes, is ubiquitous in the environment. The interactions between eDNA and biochar, a promising material widely used in soil amendment and water treatment, greatly affect the environmental behavior of eDNA. Hitherto few experimental evidences are available yet, especially on the information of thermodynamics and energy distribution to explains the interactions between biochar and eDNA. This study investigated the adsorption of herring sperm DNA (hsDNA) on pine sawdust biochar, with a specific emphasis on the adsorption thermodynamics and site energy distribution. The adsorption of hsDNA on biochar was enhanced by an increase in the pyrolysis and adsorption temperatures. The higher surface area, stronger π−π interaction, and weaker electrostatic repulsion between hsDNA and biochars prepared at high pyrolysis temperatures facilitated the adsorption of hsDNA. The thermodynamics indicated that the adsorption of hsDNA on biochar was spontaneous and endothermic. Therefore, higher temperature was beneficial for the adsorption of hsDNA on biochar; this was well explained by the increase in E^* and F(E^*) with the adsorption temperature. These results are useful for evaluating the migration and transformation of eDNA in the presence of biochar.     

Hazardous Air Pollutants (HAPs) and their Effects on Biodiversity: An Overview of the Atmospheric Pathways of Persistent Organic Pollutants (POPs) and Suggestions for Future Studies

Atmospheric change comprises many phenomena, namely climate change, acidic deposition, stratospheric ozone depletion, SMOG, increasing trend of suspended particulate matter, and hazardous air pollutants (HAPs). Among HAPs, a particular group of Persistent Organic Pollutants (POPs), such as some organochlorine pesticides, has shown a variety of toxic effects, altering the biodiversity of many ecosystems. Because of their persistence in the environment, and of their long range transport, the study of the global cycle of POPs is important in understanding how they can affect biodiversity. This can be accomplished by coupling different approaches: toxicity and ecological studies, emission estimates, and the use of global models.     

Sprawl matters: the evolution of fringe land,natural amenities and disposable income in a Mediterranean urban area

We investigate the relationship between land-use changes (1987–2007) and the spatial distribution of the average declared income of resident population in a southern European metropolitan region (Athens, Greece) as a contribution to the analysis of suburbanization processes in the Mediterranean region. To demonstrate that urban expansion is accompanied with multiple modifications in the use of the surrounding non-urban land, we developed a computational approach based on spatial indexes of landscape configuration and proximity as a result of changes in the local socio-spatial structure. Diversity in the use of land surrounding built-up parcels in the Athens’ metropolitan region increased significantly between 1987 and 2007, reflecting a progressive fragmentation of the exurban landscape. The percentage of forests and (high-quality) natural land surrounding built-up parcels increased from 8.1 to 9.4 % between 1987 and 2007. The reverse pattern was observed for (low-quality) sparsely vegetated areas, declining from 65 to 47 %. Large built-up parcels were surrounded by a higher percentage of natural land than small parcels. The largest increase over time in forest and natural land surrounding built-up parcels was observed in municipalities with high per capita declared income, and the reverse pattern was observed for sparse vegetation. Our results demonstrate that scattered urban expansion determines a polarization in suburban areas with high-quality and low-quality natural amenities. Sprawl increases economic inequality and socio-spatial disparities contributing to a spatially unbalanced distribution of natural amenities with higher consumption of high-quality land.