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In order to assess the impact of recent industrialization and land-use changes in the Can Gio Mangrove Forest, a Biosphere Reserve in Southern Vietnam, we analyzed heavy metal (HM), total organic carbon (TOC) and total nitrogen (TN) concentrations in a 210Pb-dated sediment core, allowing for the environmental reconstruction of the last three decades. C/N ratios were very high (>20) until ~1990, reflecting highly refractory organic matter. Sediment Quality Guidelines (SQG's) violations were observed particularly after the establishment of industries in the area in the late-1990s. Chromium (Cr) and copper (Cu) exceeded the threshold effect levels (TEL); whereas nickel (Ni) was above the probable effects level (PEL), identifying the risk of potential adverse biological effects. Moderate contamination, mainly from cobalt (Co) and lead (Pb), was detected by the contamination factor (CF) index, with Pb levels likely originating from mainly anthropogenic sources, particularly after ~1992, as indicated by elevated enrichment factor (EF) values. A high positive correlation was found between Pb, Cr, Cu and Ni (r ≥ 0.8), while Co, cadmium (Cd) and TOC were highly positive correlated (r = 0.9). We identified evidence of point sources, atmospheric pollution and erosion as the main contributors to enhanced HM levels. However, negative values of the Geo-accumulation index (I-geo) indicated uncontaminated sediments. This discrepancy in pollution indices was likely due to the use of shale averages instead of regional levels as background values, as well as the influence of multiple stressors. Waste emissions have increased the amount of water and soil contaminated with heavy metals such as Pb. To broaden the methods for the recycling and environmental usage of cow manure (CM) and its vermicompost (CV), CM, CV, and their derived biochars produced by the pyrolysis of CM or CV at 350 and 700 °C were used as adsorbents for Pb2+ removal in this batch adsorption experiment to reveal their different Pb2+ removal efficiencies and the underlying mechanisms. βSitosterol The batch experiment results revealed that all adsorbents rapidly removed Pb2+ within 30 min. A pH between 2.0 and 6.0 positively affected Pb2+ removal by CM and its biochar, whereas that by CV and its biochar was only positively affected by pH between 2.0 and 3.0. CV-derived biochar was more effective in the removal of Pb2+ than the other absorbents, with the maximum adsorption capacities (Qm) fitted from the Langmuir model reaching approximately 230.0 mg·g-1 and the desorption rate (DR) being approximately 0.00-0.02%. Material physiochemical characterization, including X-ray diffraction analysis, showed that high pH, high ash content, rich mineral content, and high mineral contents might have been the main reasons for more effective removal of Pb2+ from aqueous solutions by CV-derived biochar. Fourier-transform infrared analysis indicated that surface functional groups such as -OH, CO, -COO-, and C-O; original and newly produced carbonate; and phosphate in CV also led to more effective Pb2+ removal efficiency from aqueous solution via surface functional group binding. Thus, pyrolyzing CVs may be used to produce biochar as a cost-effective adsorbent for heavy metal remediation in soil and water in the future. In this study, organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in needle leaves with different ages were measured in three prevalent coniferous forests including spruce, fir and pinus in southeast Tibetan Plateau (TP) to investigate accumulation behavior of persistent organic pollutants (POPs) during entire growth cycle of needles. The accumulation concentration of POPs was higher in pinus and fir needles than in spruce needles. Concentrations for most of OCPs significantly increased with needle ages, especially dichlorodiphenyltrichloroethane (DDT) and its metabolites showed more remarkable increasing trend than hexachlorocyclohexane isomers (HCHs) and hexachlorobenzene (HCB) in the three tree species. However, age dependence accumulation of PAHs was not observed in most cases, possibly due to its easier degradation property and the influence by dramatic change of ambient atmospheric concentration of PAHs. The lipid normalized concentrations in needles exhibited similar accumulation pattern with that of dry weight basis. The controlling factors for concentration variation in needles were identified using multiple linear regression. The suitability of these needle species acting as potential passive sampler for atmospheric POPs was evaluated. The different-age needles could reflect atmospheric OCP concentrations in the past long-term trend. Findings of this study provide guidance in use of needle as passive samples for the background monitoring of the atmospheric contamination at remote and poorly accessible locations such as the TP. An integrated photo-bioelectrochemical system (IPB) for wastewater treatment combines a microbial fuel cell with an algal bioreactor, eliminating requirements for aeration, promoting electricity generation, remediating nutrients and producing algal biomass for conversion into biofuel or other bioproducts. To examine strategies for improving IPB functions of electrochemical output and nutrient removal efficiency, this study tested effects of cathode bacterial inoculation and nitrogen loading on cathode microbial community and IPB performance. IPB cathodes were inoculated with the green alga Chlorella vulgaris, in combination with nitrite-oxidizing bacteria (NOB) Nitrobacter winogradskyi, and/or ammonium-oxidizing bacteria (AOB) Nitrosomonas europaea. IPB performance was examined before and after nitrifying bacteria inoculations and under three ammonium loading concentrations in the wastewater medium. Bacterial communities in the cathode suspension and biofilm were examined by 16S rRNA gene sequence analysis. Relative to the algae only control, cathode inoculation with NOB and/or AOB improved net nutrient removal, but resulted in reduced dissolved oxygen availability, which impaired electricity generation. Higher ammonium loading increased electricity production and nutrient removal, possibly by overcoming algal-bacterial competition. Inoculation with nitrifying bacteria resulted in minor changes to total bacterial composition and AOB or NOB comprised less then 3% of total sequences after 1 month. Community composition changed more dramatically following increase in ammonium-N concentration from 40 to 80 mg L-1. Manipulation of N loading could be a useful strategy to improve IPB performance, while inoculation of AOB or NOB may be beneficial for treatment of water with high ammonium loading when N removal is the primary system goal. V.
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