Bisphenol F (BPF), an environmental estrogen, is used as a monomer in plastic industry and its environmental fate and decontamination are emerging concern. This study focused on the kinetics, influencing factors and pathways of its oxidation by MnO₂. At pH 5.5, about 90% of BPF was oxidized in 20min in a solution containing 100μM MnO₂ and 4.4μM BPF. The reaction was pH-dependent, following an order of pH 4.5>pH 5.5>pH 8.6>pH 7.5>pH 6.5>pH 9.6. Humic acids inhibited the reaction at low (≤pH 5.5) and high pH (≥pH 8.6) at high concentrations. In addition, metal ions and anions also suppressed the reaction, following the order Mn²⁺>Ca²⁺>Mg²⁺>Na⁺ and HPO₄ ²⁻>Cl⁻>NO₃ ⁻≈SO₄ ²⁻, respectively. A total of 5 products were identified, from which a tentative pathway was proposed.

The environmental risks of antibiotics have attracted lots of research attention, but their environmental behavior is not clear yet. Functionalized carbon nanotubes (CNTs) were used as model adsorbents and sulfamethoxazole (SMX) was used as a model antibiotic to investigate the effect of both cations (Ca²⁺, Cs⁺) and anions (phosphate) on antibiotics adsorption. Various mechanisms (such as electrostatic interaction, hydrophobic interaction, π–π and hydrogen bonds) play roles in SMX adsorption. Cations and anions could “wedge into” these mechanisms and thus alter SMX adsorption. This study emphasized that both increased and decreased SMX adsorption could be observed with the addition of cations/anions, depending on environmental conditions (such as pH in this current study). The net effect is the balance between the increased and decreased effects. The contribution of different mechanisms to the overall antibiotic adsorption on solid particles should be identified to accurately predict the apparent effect by cations and anions.

The phytoextraction potential of plants for removing heavy metals from polluted soils is determined by their capacity to store contaminants in aboveground organs and complex them safely. In this study, the metal compartmentation, elemental composition of zinc deposits and zinc complexation within leaves from poplars grown on soil with mixed metal contamination was analysed combining several histochemical and microanalytical approaches. Zinc was the only heavy metal detected and was stored in several organelles in the form of globoid deposits showing β-metachromasy. It was associated to oxygen anions and different cations, noteworthy phosphorous. The deposit structure, elemental composition and element ratios indicated that zinc was chelated by phytic acid ligands. Maturation processes in vacuolar vs. cytoplasmic deposits were suggested by differences in size and amounts of complexed zinc. Hence, zinc complexation by phytate contributed to metal detoxification and accumulation in foliage but could not prevent toxicity reactions therein.

Arsenic mobility may increase in liquid phase due to association with colloidal Fe oxides. We studied the association of As with Fe oxide colloids in the effluent from water-saturated soil columns run under anoxic conditions. Upon exfiltration, the solutions, which contained Fe²⁺, were re-aerated and ferrihydrite colloids precipitated. The entire amount of effluent As was associated with the ferrihydrite colloids, although PO₄ ³⁻, SiO₄ ⁴⁻, CO₃ ²⁻ and dissolved organic matter were present in the effluent during ferrihydrite colloid formation. Furthermore, no subsequent release of As from the ferrihydrite colloids was observed despite the presence of these (in)organic species known to compete with As for adsorption on Fe oxides. Arsenic was bound via inner-sphere complexation on the ferrihydrite surface. FTIR spectroscopy also revealed adsorption of PO₄ ³⁻ and polymerized silica. However, these species could not impede the quantitative association of As with colloidal ferrihydrite in the soil effluents.

An ongoing project monitors saline dust transportation and accumulation in the Western Junggar Basin to determine the rate and chemical composition of dust inputs to soils and their impact on snow/ice melt and vegetation degradation of the surrounding areas. The 1-year record from ten dust trap sites in the Ebinur region of northwest China reveals that yearly deposition rates fluctuate strongly between different sampling sites. The mass accumulation rates (fluxes) of the dust, including water-soluble solutes and trace element, range from 79 to 381 g m−2 year−1. With increasing distance from the dry lake bed, dust deposition gradually decreases. The salinity of the dust ranges from about 43 to 185 g kg−1 and the mass-soluble salt fluxes range from 4 to 61 g m−2 year−1. The types of water-soluble salt are different at different sampling sites. In all samples, the major types of water-soluble salts in the dust are sulfates and chlorides. Sulfate and chloride are the major anions while sodium and calcium are the main cations, and nitrate was not found in any dust samples. Potentially toxic trace elements such as Cd, Cr, Pb, Mn, As, Cu, and Ni are present in all samples, with high levels of Cr, Pb, Mn, Cu, and Ni. The dust is a chemical dust in that it consists of dense fine sulfates, chlorides and potentially toxic elements, and causes serious air pollution, resulting in soil salinization and vegetation degradation and accelerating snow/ice melt.

Coal is one of the major sources of fuel for electricity production and will continue to be used for many more decades. Thus, it is important to study the effects of disposal of coal burning byproducts including fly ash into the environment. In this study, the solubility of cations and anions from the fly ash in water is discussed. Also, the fractionation of different metals from fly ash in water is studied to understand which fraction of the metals would likely be mobilized. The results from these studies suggested that the metals in the fly ash are bound mostly to carbonate, organic, and residual fractions. Also, when water solubility data are modeled with a geochemical model (Visual MINTEQ), the saturation index predictions suggested that brucite (Mg(OH)2) and calcite (CaCO3) could potentially precipitate and mineralize the atmospheric CO2. Such mineralization process could potentially reduce the leaching of toxic metals from fly ash. Results from this study will be helpful in understanding the fate of different metals from fly ash land disposal environments.

The protected area “Bohemian Switzerland National Park” with its characteristic sandstone landscape was influenced by the long-term air pollution and acidic deposition within the area known as Black Triangle (located where Germany, Poland, and the Czech Republic meet, is one of the Europe’s most polluted areas). The local Upper Cretaceous sandstone is subhorizontally stratified, fine- to coarse-grained, quartz dominated, with low content of clay minerals. One of the significant negative effects of the intensive acidic deposition on sandstone outcrops has been identified as chemical (salt) weathering, i.e., a process when the porous sandstone rock is except of chemical influence attacked also by force of crystallization of growing salts crystals. Anions NO3 − together with SO4 2− and cation NH4 + were the most abundant solutes in bulk precipitation samples. Current (2002 to 2009) bulk deposition fluxes of SO4 2− determined at three sites directly in the National Park indicate decline from 23 to 16 kg−1 ha−1 year−1. Infiltration of bulk precipitation solutes into the sandstone mediates the weathering processes. Natural outflow of sandstone pore-water (sandstone percolates) can be sampled only during certain days of year when the sandstone becomes saturated with water and percolates drip out on small number of sites from roofs of overhangs. Under usual conditions percolation water evaporates at the sandstone surface producing salt efflorescences—the typical example is Pravčická brána Arch locality. The average pH of the dripping sandstone percolates was 3.76. Concentration of SO4 2− and Al in sandstone percolates reached up to 46 and 10 mg L−1. The concentration of Al in percolates has been 160-fold greater the one in the precipitation samples suggesting the sandstone as a source. The water O and H isotopic composition of percolates has been virtually identical to precipitation samples, indicating thus relatively short residence time of the solutions within the sandstone pore-spaces. Evaporation experiments with bulk precipitation and percolate samples proved possible origin of some Ca in bulk precipitation and the sandstone rock as the source of Al and possibly of K for the salt efflorescence identified on Rock Arch body.

The efficiency of UV- and VUV-based processes (UV, VUV, UV/H2O2, and VUV/H2O2) for removal of sulfamethoxazole (SMX) in Milli-Q water and sewage treatment plant (STP) effluent was investigated at 20°C. The investigated factors included initial pH, variety of inorganic anions (NO3 − and HCO3 −), and humic acid (HA). The results showed that the degradation of SMX in Milli-Q water at both two pH (5.5 and 7.0) followed the order of VUV/H2O2 > VUV > UV/H2O2 > UV. All the experimental data well fitted the pseudo-first order kinetic model and the rate constant (k) and half-life time (t 1/2) were determined accordingly. Indirect oxidation of SMX by generated .OH was the main degradation mechanism in UV/H2O2 and VUV/H2O2, while direct photolysis predominated in UV processes. The quenching tests showed that some other reactive species along with .OH radicals were responsible to the SMX degradation under VUV process. The addition of 20 mg L−1 HA significantly inhibited SMX degradation, whereas, the inhibitive effects of NO3 − and HCO3 − (0.1 mol L−1) were observed as well in all processes except in UV irradiation for NO3 −. The removal rate decreased 1.7–3.6 times when applying these processes to STP effluent due to the complex constituents, suggesting that from the application point of view the constituents of these complexes in real STP effluent should be considered carefully prior to the use of UV-based processes for SMX degradation.

Due to increased whole-tree harvesting in Swedish forestry, concern has been raised that a depletion of nutrients in forest soil will arise. The Swedish Forest Agency recommends compensation fertilization with wood ash to ensure that unwanted effects are avoided in the nutrient balance of the forest soil and in the quality of surface water. In this investigation, the chemistry of two first-order streams, of which one was subjected to a catchment scale treatment with 3 tonnes of self-hardened wood ash/ha in the fall of 2004, was monitored during 2003–2006. Large seasonal variations in stream water chemistry made changes due to ash application difficult to detect, but evaluating the ash treatment effects through comparison of the stream water of the treated catchment with the reference was possible via statistical tools such as randomized intervention analysis in combination with cumulative sum charts. The wood ash application did not yield any significant effect on the pH in the stream water and hence did not affect the bicarbonate system. However, dissolved organic carbon increased, a previously unreported effect of WAA, bringing about an increase of organic anions in the stream water. The wood ash application also induced significant increases for Ca, Mg, K, Si, Cl and malonate, of which K was most prominent. Although significant, the changes induced by the wood ash application were all small compared to the seasonal variations. As a tool to counteract acidification of surface waters, WAA seems to have limited initial effects.

The present study was conducted in tropical Sal forest ecosystem of the Doon valley in the Indian Himalayas to assess the critical load of sulfur and nitrogen and their exceedances. The observed pattern of throughfall ionic composition in the study are Ca2+>K+>Mg2+>Cl−> HCO3−> Na+>NO3 −> SO3 2−≥ NH4 +>F−. The sum of cation studied is 412.29 μeq l−1 and that of anions is 196.98 μeq l−1, showing cation excess of 215.31 μeq l−1. The cations, namely Ca2+, Mg2+, K+, Na+, and NH4 +, made a contribution of about 67% of the total ion strength, where as anion comprising of SO4 2−, Cl−, NO3 −, and HCO3 − contributed 33%. The chief acidic components were Cl– (12%) and HCO3 − (8%), while the presence of SO4 2− (5%) and NO3 − (6%), respectively. Percentage contribution of bole to total aboveground biomass was ∼72.38% in comparison to 2.24–2.93% of leaf biomass, 10.34–10.96% of branch biomass and 13.21–17.07% of bark biomass. There was high and significant variation (P < 0.001) in the total aboveground biomass produced at different sites. The aboveground net primary productivity (ANPP) in these sites ranged between 2.09 and 9.22 t ha−1 year−1. The base cations and nitrogen immobilization was found to be maximum in bole. The net annual uptake of the base cations varied from 306.85 to 1,311.46 eq ha−1 year−1 and of nitrogen from 68.27 to 263.51 eq ha−1 year−1. The critical appraisal of soil showed that cation exchange capacity lied between 18.37 and 10.30 Cmol (p+) kg−1. The base saturation percentage of soil was as high as 82.43% in Senkot, whereas in Kalusidh it was just 44.28%. The local temperature corrected base cation weathering rates based on soil mineralogy, parent material class, and texture class varied from 484.15 to 627.25 eq ha−1 year−1, showing a weak potentiality of the system to buffer any incoming acidity and thus providing restricted acid neutralizing capacity to keep the ecosystem stable under increased future deposition scenarios in near future. The appreciable BS of the soil indicates the presence of intense nutrient phytorecycling forces within this climate and atmospheric deposition in replenishing base cations in the soil, which includes intrinsic soil-forming processes, i.e., weathering. The highest value of critical load for acidity was 2,896.50 eq ha−1 year−1 and the lowest was 2,792.45 eq ha−1 year−1. The calculated value of the minimum critical loads for nitrogen varied from 69.77 to 265.01 eq ha−1 year−1, whereas the maximum nitrogen critical load ranged between 2,992.63 and 4,394.45 eq ha−1 year−1. The minimum and the maximum critical loads of sulfur ranged between 2,130.49 and 3,261.64 eq ha−1 year−1 and 2,250.58 and 3,381.73 eq ha−1 year−1, respectively. The values of exceedance of sulfur and nitrogen were negative, implying that in the current scenario Sal forests of the Doon valley are well protected from acidification.