The concentrations and fractions of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in soils collected from Hailuogou Glacier foreland in eastern Tibetan Plateau were analyzed to decipher their mobility, and their eco-risk was assessed combined with multiple environmental indices. The concentrations of Cd were more than ten times higher than its local background in the O horizon and nearly three times higher in the A horizon. The concentrations of Pb and Zn were relatively high in the O horizon, whereas that of Cu increased with soil depth. The main fractions of metals in the surface horizons were reducible and acid-soluble for Cd, oxidizable and residual for Cu, reducible and oxidizable for Pb, and reducible and residual for Zn. The metal mobility generally followed the order of Cd > Pb > Zn > Cu in the O horizon and Cd > Pb > Cu > Zn in the A horizon. Sorption and complexation by soil organic matters imparted an important effect on the mobilization and transformation of Cd, Pb, and Zn in the soils. The oxidizable Cu fraction in the soils showed significant correlation with organic matters, and soil pH mainly modulated the acid-soluble and reducible Cu fractions. The concentrations and other environmental indices including contamination factor, enrichment factor, geoaccumulation index, and risk assessment index revealed that Cd reached high contamination and very high eco-risk, Pb had medium contamination but low eco-risk, Zn showed low contamination and low eco-risk, and Cu was not contaminated in the soils. The data indicated that Cd was the priority to concern in the soils of Hailuogou Glacier catchment.

The morphological, physiological, and biochemical parameters of 6-week-old seedlings of Scots pine (Pinus sylvestris L.) were studied under deficiency (1.2 nM) and chronic exposure to copper (0.32, 1, 2.5, 5, and 10 μM CuSO₄) in hydroculture. The deposit of copper in the seed allowed the seedlings to develop under copper deficiency without visible disruption of growth. The high sensitivity of Scots pine to the toxic effects of copper was shown, which manifested as a significant inhibition of growth and development. The loss of dominance of the main root and a strong inhibition of lateral root development pointed to a lack of adaptive reorganization of the root system architecture under copper excess. A preferential accumulation of copper in the root and a minor translocation in aerial organs confirmed that Scots pine belongs to a group of plants that exclude copper. Selective impairment in the absorption of manganese was discovered, under both deficiency and excess of copper in the nutrient solution, which was independent of the degree of development of the root system. Following 10 μM CuSO₄ exposure, the absorption of manganese and iron from the nutrient solution was completely suppressed, and the development of seedlings was secured by the stock of these micronutrients in the seed. The absence of signs of oxidative stress in the seedling organs was shown under deficiency and excess of copper, as evidenced by the steady content of malondialdehyde and 4-hydroxyalkenals. Against this background, no changes in total superoxide dismutase activity in the organs of seedlings were revealed, and the increased content of low-molecular-weight antioxidants was observed in the roots under 1 μM and in the needles under 5 μM CuSO₄ exposures.

Titania/silica nanomaterials have many possible applications; however, they can be toxic to living organisms, particularly if the material accumulates in niche environments, e.g. areas colonised by actinomycetes. This study therefore investigated the effect of non-activated and UV light-activated titania/silica nanospheres on an environmental Streptomyces strain. The bacteria were incubated with the nanospheres and subsequently cultured on solid medium. The morphology and elemental composition were analysed using optical and electron microscopy (TEM, STEM) and energy-dispersive X-ray spectroscopy (EDX). The appearance of Streptomyces sp. in the experimental and control samples demonstrated that the nanospheres did not have bactericidal properties in the used dose. Furthermore, the observed strain not only survived in the presence of the nanomaterial but also appeared to play a role in its dissolution with an accumulation of the titanium in the intracellular globules of polyphosphate (volutin). Additionally, it was discovered that the UV light-activated titanium dioxide altered the ability of the bacteria to secrete humic acid. The reported phenomenon might be made possible through an accumulation of titanium in the volutin compounds. These findings suggest that streptomycetes could be employed to participate in the dissolution of nanomaterials which enter the natural environment.

Mercury (Hg), aside from having high toxicity, is characterized by its ability to biomagnify in the marine trophic chain. This is an important problem especially in estuaries, or in the coastal zone, particularly near the mouths of large rivers. This study was conducted in the years 2001–2011, in the coastal zone of the Baltic Sea near to the mouth of the River Vistula, which is the second biggest river discharging into the Baltic. Mercury concentration was measured in the tissues and organs of cod, flounder, herring, seals (living in the wild and in captivity), great black-backed gulls, and African penguins from Gdańsk Zoo, and also in human hair. Penguins and seals at the seal sanctuary in Hel were fed only herring. In marine birds and mammals and in the pelagic herring, the highest Hg concentration was observed in the kidney and in the liver, while in cod and flounder (located on a higher trophic level) the muscles were the most contaminated with mercury. In gray seals living in the seal sanctuary, Hg concentration in all analyzed tissues and organs except the kidneys was lower in comparison with seals living in the wild. The comparatively small share of fish in the diet of local Polish people and their preference towards the consumption of herring contributed to low concentration of Hg in their hair. The protective mechanisms related to detoxification and elimination of mercury were shown to be more effective in the seals than in the penguins, despite the former consuming around 10 times more food per day.

The overall purpose of this work was to evaluate the treatment system performance of sequential hybrid bioreactors, one without aeration and another with intermittent aeration, in the bioremoval of Cr(VI) and total chromium and in the removal of total organic carbon (TOC). The saturation kinetic curves were studied with initial concentrations of Cr(VI) of 80, 120 and 150 mg L⁻¹. A reference test was performed before adding chromium to the system, with the intention of checking the influence of the presence of chromium on the TOC removal. During the bioreactor regeneration, the chromium removal was evaluated, after each kinetic studied. For kinetics with 80 mg L⁻¹ of Cr(VI), the results showed that after 600 h of operation, there was no saturation of bioreactors, yielding 87 % overall removal of Cr(VI) and 62 % chromium total. For initial concentrations of Cr(VI) of 120 and 150 mg L⁻¹, only the non-aerated bioreactor reached saturation after 228 and 216 h of operation, respectively. In regeneration, it was found in all the assays performed that the chromium concentration at the outlet of the bioreactor became almost zero at a maximum of 72 h of operation. In the blank test, the TOC removal achieved was 64 %, while in the three tests in the presence of chromium, this was approximately 55 % (80 mg L⁻¹), 41 % (120 mg L⁻¹) and 31 % (150 mg L⁻¹). After cell lysis by ultrasound, it was found that the chromium concentration retained inside there was lower than the concentrations present in the environment.

Wastewaters from civil and industrial use, which contain high concentration of heavy metals, pose the problem for their correct disposal. They cannot be directly discharged in sewage systems, as metal ions represent a serious problem not only for human health but also for the environment. In this paper, the removal of nickel, cobalt, chromium, and zinc ions from synthetic liquid wastes was carried out, by using a micellar-enhanced ultrafiltration (MEUF) process; an ultrafiltration (UF) membrane (a monotubular ceramic of molecular weight cutoff 210 kDa) together with sodium dodecyl sulfate (SDS) as an anionic surfactant was used, in a lab-scale experimental device. The synthetic liquid contained 10-mg/L metal ions (Cr, Zn, Co, Ni), while SDS concentration varied from values above and below critical micellar concentration (CMC). The experiments were carried out at room temperature (25 °C). Results achieved showed that SDS was able to bind metal ions, resulting in a strong increase of rejection coefficient, which reached highest values in case of SDS concentration below CMC, unexpectedly.

This paper attempts to investigate the emissions embodied in Australia’s economic growth and disaggregate primary energy sources used for electricity production. Using time series data over the period of 1990–2012, the ARDL bounds test approach to cointegration technique is applied to test the long-run association among the underlying variables. The regression results validate the long-run equilibrium relationship among all vectors and confirm that CO₂ emissions, economic growth, and disaggregate primary energy consumption impact each other in the long-run path. Afterwards, the long- and short-run analyses are conducted using error correction model. The results show that economic growth, coal, oil, gas, and hydro energy sources have positive and statistically significant impact on CO₂ emissions both in long and short run, with an exception of renewables which has negative impact only in the long run. The results conclude that Australia faces wide gap between emission abatement policies and targets. The country still relies on emission intensive fossil fuels (i.e., coal and oil) to meet the indigenous electricity demand.

Anthropic eutrophication is one of the most widespread problems affecting water quality worldwide. This condition is caused by excessive nutrient inputs to aquatic systems, and one of the main consequences is accelerated phytoplankton growth. Eutrophication can lead to damage to human health, the environment, society, and the economy. One of the most serious consequences of eutrophication is the proliferation of cyanobacteria that can release toxins into the water. The aim of this research was to evaluate the trophic condition of a tropical reservoir over the course of time, using a database extending over 15 years to investigate relationships with environmental conditions, considering spatial heterogeneity and seasonality, as well as inter-relations between trophic state indicators. Data for chlorophyll-a, total phosphorus, and total nitrogen were collected from 2000 to 2014, and cyanobacteria abundance was determined from 2004 to 2014. The trophic state index was also calculated. The results demonstrated the existence of two distinct compartments in the reservoir: one lotic and the other lentic. No relationship was observed between chlorophyll-a and phosphorus. The results suggested that phytoplankton growth was mainly controlled by nitrogen concentrations. These conditions favored cyanobacteria predominance, resulting in increasing abundance of these potentially toxic bacteria over time. The model obtained indicated hypereutrophic conditions, with high phytoplankton biomass and cyanobacteria abundance during the next years likely to affect the uses of the water of the reservoir.

Due to their metal removal ability, bacterial biosorbents can be effectively used for the treatment of wastewaters containing heavy metals. Searching for bacterial biosorbents for hazardous heavy metals like cadmium is a pivotal for remediation efforts. The gene cadA, that mediates resistance to cadmium over an ATP-dependent efflux mechanism, provides a good target for the selection of potential cadmium biosorbents. For this reason, in this study, a 36-mer-oligonucleotide DNA probe based on the entire 3.5-kb BglII-XbaI fragment of cadA operon from staphylococcal plasmid pI258 was prepared by using Vector NTI Express software. Under the hybridization conditions of 46 °C, 50 % formamide, and 0.028 M NaCl, the designed cadA probe appeared to be highly specific to the cadA-positive Staphylococcus warneri and Delftia acidovorans isolates tested. The results indicated that the newly designed cadA-targeted DNA probe has potential as a specific, sensitive, and quantitative tool in selecting and in situ screening of potential cadmium biosorbents.

Phosphorus (P) associated with minerogenic particles delivered from watersheds can interfere with the common use of total P (TP) concentration as a trophic state metric in lacustrine systems, particularly proximate to tributary entries, because of its limited bioavailability. The concentration of unavailable minerogenic particulate P (PPₘ/ᵤ), where it is noteworthy, should be subtracted from TP in considering primary production potential and trophic state levels. A first mass balance model for PPₘ/ᵤ is developed and tested here for Cayuga Lake, New York. This is supported by a rare combination of detailed information for minerogenic particle level dynamics for the tributaries and lake, the bioavailability of tributary particulate P (PP), and previously tested hydrothermal/transport and minerogenic particle concentration submodels. The central roles of major runoff events and localized tributary loading at one end of the lake in driving patterns of PPₘ/ᵤ in time and space are well simulated, including (1) the higher PPₘ/ᵤ concentrations in a shallow area (“shelf”) adjoining the inputs, relative to pelagic waters, following runoff events, and (2) the positive dependence of the shelf increases on the magnitude of the event. The PPₘ/ᵤ component of P was largely responsible for the higher summer average TP on the shelf vs. pelagic waters and the exceedance of a TP water quality limit on the shelf. The effective simulation of PPₘ/ᵤ allows an appropriate adjustment of TP values to avoid overrepresentation of potential primary production levels.