Magnetic and geochemical parameters of soils are determined with respect to geology, pedogenesis and anthropopression. Depending on local conditions these factors affect magnetic and geochemical signals simultaneously or in various configurations. We examined four type of soils (Entic Podzol, Eutric Cambisol, Humic Cambisol and Dystric Cambisol) developed on various bedrock (the Tumlin Sandstone, basaltoid, amphibolite and serpentinite, respectively). Our primary aim was to characterize the origin and diversification of the magnetic and geochemical signal in soils in order to distinguish the most reliable methods for correct interpretation of measured parameters. Presented data include selected parameters, both magnetic (mass magnetic susceptibility – χ, frequency-dependent magnetic susceptibility – χfd and thermomagnetic susceptibility measurement – TSM), and geochemical (selected heavy metal contents: Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn). Additionally, the enrichment factor (EF) and index of geoaccumulation (Igeo) were calculated. Our results suggest the following: (1) the χ/Fe ratio may be a reliable indicator for determining changes of magnetic signal origin in soil profiles; (2) magnetic and geochemical signals are simultaneously higher (the increment of χ and lead and zinc was noted) in topsoil horizons because of the deposition of technogenic magnetic particles (TMPs); (3) EF and Igeo evaluated for lead and zinc unambiguously showed anthropogenic influence in terms of increasing heavy metal contents in topsoil regardless of bedrock or soil type; (4) magnetic susceptibility measurements supported by TSM curves for soil samples of different genetic horizons are a helpful tool for interpreting the origin and nature of the mineral phases responsible for the changes of magnetic susceptibility values.

Lead (Pb) isotope has been extensively used to identify sources of Pb and apportion their contributions in the environment. Conventionally, isotope ratios are used to express Pb isotopic composition. However, the linear combination of Pb isotope ratios is not consistent with mass balance. Moreover, the graphical presentations based on Pb isotope ratios are always inconsistent when different Pb isotope ratios are used. In this study, we proposed to use fractional abundance to express Pb isotopic composition to achieve more accurate and reliable source apportionment. A new method (rotation-projection method) based on fractional abundance was developed in this research. The new method compared favorably to the isotopic ratio-based method and to another fractional abundance based method using default 204Pb value (0) (Walraven’s method). It allows to present four-dimensional (4-D) Pb isotope fractional abundance data in a 3-D plot. In the meantime, due to the low variation of the fractional abundance of 204Pb in the terrestrial ecosystem, the terrestrial Pb isotope fractional abundance data fell nearly on a plane, which further allows to plot the Pb isotope fractional abundance data on a two-dimensional diagram. Proper presentation of the isotopic composition data helps to achieve more accurate and reliable source identification and apportionment.

In order to evaluate the impact of semi-intensive shrimp farming, comparisons between Control and Impact areas were made based on multiple lines of evidence using an asymmetrical design. Water and sediment samples were collected in four shrimp farms located in Todos os Santos Bay, Bahia, Brazil. Nutrients, trace elements and macrobenthic assemblages were evaluated using uni- and multivariate analyzes.Significant differences were observed between Impact and Control areas for the water column dataset (i.e., ancillary variables, SPM, dissolved nutrients and major and trace elements in SPM), whereas no significant differences were observed for the chemistry of sediments. Macrobenthic assemblages were negatively affected by shrimp farm activities. Impacted sites presented the lowest abundance, richness and different structure of macrofaunal benthic assemblages. Farms clearly produced negative impacts in the Todos os Santos Bay. This conclusion was only possible to be reached through the use of multiple lines of evidence. Chemistry and benthic assemblages data combined produced a better description of the quality and impacts of the evaluated environments. Different conclusions would have been reached if chemistry and ecology results were studied separately vs. together.

The application of road deicing salts has led to the salinization of freshwater ecosystems in northern regions worldwide. Increased chloride concentrations in lakes, streams, ponds, and wetlands may negatively affect freshwater biota, potentially threatening ecosystem services. In an effort to reduce the effects of road salt, operators have increased the use of salt alternatives, yet we lack an understanding of how these deicers affect aquatic communities. We examined the direct and indirect effects of the most commonly used road salt (NaCl) and a proprietary salt mixture (NaCl, KCl, MgCl2), at three environmentally relevant concentrations (150, 470, and 780 mg Cl−/L) on freshwater wetland communities in combination with one of three biotic stressors (control, predator cues, and competitors). The communities contained periphyton, phytoplankton, zooplankton, and two tadpole species (American toads, Anaxyrus americanus; wood frogs, Lithobates sylvaticus). Overall, we found the two road salts did not interact with the natural stressors. Both salts decreased pH and reduced zooplankton abundance. The strong decrease in zooplankton abundance in the highest NaCl concentration caused a trophic cascade that resulted in increased phytoplankton abundance. The highest NaCl concentration also reduced toad activity. For the biotic stressors, predatory stress decreased whereas competitive stress increased the activity of both tadpole species. Wood frog survival, time to metamorphosis, and mass at metamorphosis all decreased under competitive stress whereas toad time to metamorphosis increased and mass at metamorphosis decreased. Road salts and biotic stressors can both affect freshwater communities, but their effects are not interactive.

Rapid industrialization and urbanization has caused large emission and potential contamination of mercury (Hg) in urban environment. However, little is known about the impact of socioeconomic factor on Hg accumulation in sediment. In the present study, historical record of anthropogenic Hg deposition of Shanghai was reconstructed by using three sediment cores from three park lakes (C1: Luxun Park; C2: Fuxing island Park; C3: Xinjiangwan Park). Meanwhile, the influence of socioeconomic factor to Hg emissions and sedimentary record was calculated based on an extended STIRPAT (stochastic impacts by regression on population, affluence and technology) model. The profiles of Hg levels and fluxes in the three sediment cores showed that Shanghai has recently undergone urbanization. The anthropogenic Hg fluxes exhibited fluctuant increases from ∼1900 to present and accelerated after the establishment of the People’s Republic of China in 1949 and the implementation of reform and opening up policy in 1978. The mean flux ratios of Hg in post-2000 were 2.2, 12, and 2.7 in the C1, C2 and C3 cores, respectively. The extended STIRPAT model was constructed based on strong positive relationships between socioeconomic factors and Hg fluxes, revealing that the proportion of coal consumption, the urbanization rate, and the proportion of heavy industry were the three most important driving factors for Hg accumulations in urban sediment of Shanghai.

The antibiotic resistance genes (ARGs) from urban waste may spread to the environment with the discharge of leachate. Fifteen types of ARGs, including tetracycline, sulfonamides, AmpC β-lactamase and the class 1 integron gene were detected in the samples from the largest leachate treatment plant (LTP) in Guangzhou and its effluent receiving bodies (soil and surface water). The results showed that ARGs in leachates were in high levels and varied with seasons. The abundance of ARGs in the influent from high to low was in the turn of summer, winter, spring. About 2 to 4 orders of magnitude of ARGs were eliminated by the whole leachate treatment process. The predominant ARGs in the receiving soil were intI1, tetB, sul2, tetA and tetX, while those in the receiving surface water were sul2, intI1 and sul1, and the concentrations of ARGs in the receiving bodies were higher than those in the other natural bodies by 1 to 2 orders of magnitude. In addition, the results of bivariate correlation analysis showed that the abundances of ARGs (tetC, tetW, sul1, sul2, intI1 and FOX) were in significant correlation with the concentrations of heavy metals (Cu, Zn, Ni and Cr) (p < 0.05). LTPs are more likely to be sources of ARGs than wastewater treatment plant (WWTP) and need to be focused on.

Plastic pollution is a growing global concern. In the present study, we investigated plastic pollution in 21 species of sea fish and 6 species of freshwater fish from China. All of the species were found to ingest micro- or mesoplastics. The average abundance of microplastics varied from 1.1 to 7.2 items by individual and 0.2–17.2 items by gram. The average abundance of mesoplastics varied from 0.2 to 3.0 items by individual and 0.1–3.9 items by gram. Microplastics were abundant in 26 species, accounting for 55.9–92.3% of the total number of plastics items in each species. Thamnaconus septentrionalis contained the highest abundance of microplastics (7.2 items/individual). The average abundance of plastics in sea benthopelagic fishes was significantly higher than in freshwater benthopelagic fishes by items/individual. The plastics were dominanted by fiber in shape, transparent in color and cellophane in composition. The proportion of plastics in the stomach to the intestines showed great variation in different species, ranging from 0.5 to 1.9 by items/individual. The stomach of Harpodon nehereus and intestines of Pampus cinereus contained the highest number of plastics, (3.3) and (2.7), respectively, by items/individual. Our results suggested that plastic pollution was widespread in the investigated fish species and showed higher abundance in comparison with worldwide studies. The ingestion of plastics in fish was closely related to the habitat and gastrointestinal tract structure. We highly recommend that the entire gastrointestinal tract and digestion process be used in future investigations of plastic pollution in fish.

In the past few decades, extensive application of azoxystrobin has led to great concern regarding its adverse effects on aquatic organisms. The objective of the present study was to evaluate the reproductive toxicity of azoxystrobin to zebrafish. After adult zebrafish of both sexes were exposed to 2, 20 and 200 μg/L azoxystrobin for 21 days, egg production, the fertilization rate, the gonadosomatic index (GSI) and hepatosomatic index (HSI), 17β-estradiol (E2), testosterone (T) and vitellogenin (Vtg) concentrations, and histological alterations in the gonads and livers were measured. Meanwhile, expression alterations of genes encoding gonadotropins and gonadotropin receptors (fshb, lhb, fshr and lhr), steroid hormone receptors (era, er2b and ar), steroidogenic enzymes (cyp11a, cyp11b, cyp17, cyp19a, cyp19b, hsd3b and hsd17b) in the hypothalamic-pituitary-gonad (HPG) axis and vitellogenin (vtg1 and vtg2) in the livers were also investigated. The results showed that reduced egg production and fertilization rates were observed at 200 μg/L azoxystrobin. In female zebrafish, reduced E2 and Vtg concentrations, decreased GSI, increased T concentrations, and histological alterations in the ovaries and livers were observed at 200 μg/L azoxystrobin, along with significant down-regulation of lhb, cyp19b, lhr, cyp19a, vtg1 and vtg2, and up-regulation of cyp17, hsd3b and hsd17b. In male zebrafish, increased E2 and Vtg concentrations, reduced T concentration and GSI, and histological alterations in the testes and livers were observed after exposure to 20 and 200 μg/L azoxystrobin, along with significant up-regulations of cyp19b, cyp11a, cyp17, cyp19a, hsd3b and hsd17b, vtg1 and vtg2. Moreover, cyp11a, hsd3b, cyp19a, vtg1 and vtg2 in male zebrafish were significantly up-regulated after treatment with 2 μg/L azoxystrobin. The results of the present study indicate that azoxystrobin led to reproductive toxicity in zebrafish and male zebrafish were more sensitive to azoxystrobin than female zebrafish.

Jiulong River Estuary, located in southern China, was heavily contaminated by metal pollution. In this study, the estuarine oysters Crassostrea hongkongensis were transplanted to two sites with similar hydrological conditions but different levels of metal pollution in Jiulong River Estuary over a six-month period. We characterized the time-series change of metal bioaccumulation and final metabolomics responses of oysters. Following transplantation, all metals (Cd, Cu, Cr, Ni, Pb, and Zn) in the oyster digestive glands had elevated concentrations over time. By the end of six-month exposure, Cu, Zn and Cd were the main metals significantly differentiating the two sites. Using 1H NMR metabolite approach, we further demonstrated the disturbance in osmotic regulation, energy metabolism, and glycerophospholipid metabolism induced by metal contaminations. Six months later, the oysters transplanted in the two sites showed a similar metabolite variation pattern when compared with the initial oysters regardless of different metal levels in the tissues. Interestingly, by comparing the oysters from two sites, the more severely polluted oysters accumulated significantly higher amounts of osmolytes (betaine and homarine) and lower energy storage compounds (glycogen) than the less polluted oysters; these changes could be the potential biomarkers for different levels of metal pollution. Our study demonstrated the complexity of biological effects under field conditions, and NMR metabolomics provides an important approach to detect sensitive variation of oyster inner status.

Light pollution or artificial light at night (ALAN) is increasingly recognised to be an important anthropogenic environmental pressure on wildlife, affecting animal behaviour and physiology. Early life experiences are extremely important for the development, physiological status and health of organisms, and as such, early exposure to artificial light may have detrimental consequences for organism fitness. We experimentally manipulated the light environment of free-living great tit nestlings (Parus major), an important model species in evolutionary and environmental research. Haptoglobin (Hp) and nitric oxide (NOx), as important indicators of immunity, health, and physiological condition, were quantified in nestlings at baseline (13 days after hatching) and after a two night exposure to ALAN. We found that ALAN increased Hp and decreased NOx. ALAN may increase stress and oxidative stress and reduce melatonin which could subsequently lead to increased Hp and decreased NOx. Haptoglobin is part of the immune response and mounting an immune response is costly in energy and resources and, trade-offs are likely to occur with other energetically demanding tasks, such as survival or reproduction. Acute inhibition of NOx may have a cascading effect as it also affects other physiological aspects and may negatively affect immunocompetence. The consequences of the observed effects on Hp and NOx remain to be examined. Our study provides experimental field evidence that ALAN affects nestlings' physiology during development and early life exposure to ALAN could therefore have long lasting effects throughout adulthood.