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Manure, soil, and vegetable samples were collected from different-sized livestock farms in Xinxiang, China. The residues of sulfadiazine, sulfamonomethoxine, and sulfamethoxazole were analyzed by high-performance liquid chromatography. The results indicated that the concentration ranges of the three total sulfonamides in manure, soil, and vegetables were 10.13–566.23 µg kg−1, 7.60–176.26 µg kg−1, and 0–32.70 µg kg−1, respectively. The mean concentrations were 219.71 µg kg−1, 70.73 µg kg−1, and 7.08 µg kg−1 for manure, soil, and vegetables, respectively. The mean concentrations in soil were lower than the ecotoxic effect trigger value (100 µg kg−1), indicating a low risk for organisms in soil. The concentrations of the three sulfonamides varied significantly in different types of vegetables and all were lower than the acceptable daily intake value (50 µg (kg day)−1). However, the potential ecotoxicity and danger to human and animal health via accumulation of the antibiotic in the food chain cannot be ignored.

The joint effect of chlorimuron-ethyl and cadmium (Cd) on biomass growth and cadmium accumulation in wheat (Triticum aestivum L.) was investigated and compared with single-factor effect of soil cadmium pollution. The results showed that dry biomass of wheat had significantly (p

In a microcosm experiment, the amplified ribosomal DNA restriction analysis was adopted to investigate the Pseudomonas community structure in soils applied with different concentrations (0, 50, 150, and 250 mg/kg) of acetochlor, and an in vitro assay was made to examine the antagonistic activity of isolated Pseudomonas strains acting on soil-borne pathogen Rhizoctonia solani. The results showed that acetochlor application changed the community structure of Pseudomonas in aquic brown soil. The diversity of Pseudomonas and the amount of isolated Pseudomonas strains with antagonistic activity decreased with an increasing acetochlor concentration, and the toxic effect of acetochlor reached to a steady level at 150-250 mg/kg.

The effects of chemical amendments including zeolite, compost and mesoporous molecular sieves (MCM-41) on the extractability and speciation of heavy metals (Cd, Pb and Cu) in a contaminated soil were investigated. Results showed that the application of soil amendments decreased Cd, Pb and Cu uptake by the shoots of pakchoi, up to 44.2-53.2%, 30.2-42.7% and 16.9-22.1%, respectively, compared with the control. Among the three amendments, zeolite and MCM-41 were more efficient in reducing Cd and Cu uptake, while compost was more efficient in reducing Pb uptake by the plants. The growth of pakchoi was improved in amended soils due to the action of chemical amendments.

Soil pollution by cadmium has been a long standing ecological problem in Zhangshi Irrigation Area, Shenyang, China, as a result of the 30-year practice of irrigation with wastewater containing high levels of heavy metals. To evaluate the adverse impact of cadmium contamination on soil ecosystems, the responses of soil microbiota to both long-term and short-term cadmium stress were studied by molecular microbial community profiling with denaturating gradient gel electrophoresis (DGGE) analysis. Our results show that soil characteristics and nutrient conditions were likely more important than cadmium toxicity in shaping the soil bacterial community structure in the long term. In comparison, soil microbial genetic diversity was shown to be more closely correlated to cadmium levels under short-term cadmium stress, with the highest microbial genetic diversity occurring at mild cadmium stress conditions, which might be attributed to the enrichment of metal-resistant microbial populations through mechanisms of competitive selection and genetic adaptation. In contrast, severe cadmium stress likely presented a condition that fewer microbial populations could survive, thus leading to reduced microbial genetic diversity.

The dechlorination of pentachlorophenol (PCP) by zerovalent iron (Fe(0)) in presence of low molecular weight carboxylic acids was investigated. The experimental results showed that oxalic acid was advantaged among the selected acids for the dechlorination of PCP. The lower pH value and the higher dosage of Fe(0) were favorable for the enhancement of dechlorination efficiency. With their strong complexing and pH buffering properties, carboxylic acids favored the fresh surface of iron, which benefits to the dechlorination of PCP by Fe(0). Moreover, the oxalate-iron complexes have more reductive activities and then lead to the highest dechlorination efficiency of PCP by Fe(0).

The remediation of diesel fuel contaminated soil over a 2-year period by the plant-microorganism synergy was evaluated. Results indicated that the growth of Astragalus adsurgens was affected significantly, when the diesel fuel concentration was higher than 10 g kg(-1) dry soil. After a 2-year period, the removal of diesel fuel was67%, and about 58-70% removal of aromatic hydrocarbons was obtained in these treatments. The removal of diesel fuel and its components was 13-30% higher than that of plant alone. These results show that an appropriate plant-microorganism synergy may serve as a low-cost, effective remedial technology for diesel-contaminated soil.

In order to solve environmental problems resulting from ammonia released into the atmosphere, the emission of ammonia contamination from monosodium glutamate (MSG) production was quantitatively observed, and the relationships with relevant influencing factors (ammonium-N, nitrate/nitrite-N and pH) were statistically analyzed. The results indicated that the release of gaseous ammonia from MSG production including the treatment and discharge of wastewater was highly dependent on the technical processes utilised. The flux of ammonia released from the fermentation workshop was highest, up to 8.98 x 10(5) mg m(-3) min(-1), and the flux from the sugar-refining workshop was lowest, only 85.1 mg m(-3) min(-1). The release of gaseous ammonia during the whole MSG production was significantly proportional to the concentration of ammonium-N in the discharged solution, and exponentially proportional to the concentrations of nitrate-nitrogen and nitrite-nitrogen in the discharged solution. Although there was no linear relationship between the flux of ammonia released during the whole MSG production and pH values in the discharged solution, pH was significantly related to the flux of ammonia released during the treatment and discharge of wastewater.

This paper demonstrates the Pb(2+) adsorption capacity and adsorption rate of Saccharomyces cerevisiae by both static and dynamic testing to verify its feasibility as a heavy metal bio-absorbent in wastewater treatment. The static testing was divided into two parts. First, we tested S. cerevisiae by itself, and then we tested immobilized S. cerevisiae. In static testing of the non-immobilized S. cerevisiae, the Pb(2+) adsorption capacity and adsorption rate increased up to 6.52 mg/g and 52.94%, respectively, with time. After immobilization, the Pb(2+) adsorption capacity and adsorption rate reached 10 mg/g and 80%, respectively. In dynamic testing, the optimal saturated adsorption capacity of immobilized S. cerevisiae for Pb(2+) was 6.64 mg/g. In addition to the static and dynamic testing of adsorption capacity and rate, we used SEM imaging to analyze the mechanics of adsorption, and the images showed that the cell wall played the major roll in Pb(2+) adsorption.

Application of synthetic chelates such as ethylene diamine tetraacetic acid (EDTA) has been proposed as an alternative technology for phytoextraction of contaminated soils. In a pot experiment, the effects of EDTA application at three growing stages on growth and Cd uptake and accumulation of Solanum nigrum L. were investigated. The results showed that the 0.1 g/kg EDTA treatment was the most effective treatment, in which the concentrations of Cd in stems and leaves increased significantly compared with the control (Cd only), and the accumulation of Cd in shoots increased by 51.6%, 61.1% and 35.9% at the seedling, flowering and mature stages, respectively. Moreover, at the flowering stage, the height, dry shoot biomass and Cd accumulation in the plants reached the maximum, which were 18.9 cm, 1.8 g/plant and 292.8 microg/pot, respectively. However, higher rate of EDTA (0.5 g/kg) could reduce the plant biomass and the total amount of Cd removed. The results indicated that moderate rate of EDTA applied at the flowering stage would be important to enhance phytoremediation efficiency in practice.

In the process of bioremediation in the soil contaminated by different oil concentrations, the changes in the microbial numbers (bacteria and fungi) and the enzyme (catalase (CAT), polyphenol oxidase (PPO) and lipase) activities were evaluated over a 2-year period. The results showed that the microbial numbers after 2-year bioremediation were one to ten times higher than those in the initial. The changes in the bacterial and the fungal populations were different during the bioremediation, and the highest microbial numbers for bacteria and fungi were 5.51 x 10(9) CFU g(-1) dry soil in treatment 3 (10,000 mg kg(-1)) in the initial and 5.54 x 10(5) CFU g(-1) dry soil in treatment 5 (50,000 mg kg(-1)) after the 2-year bioremediation period, respectively. The CAT and PPO activities in the contaminated soil decreased with increasing oil concentration, while the lipase activity increased. The activities of CAT and PPO improved after the bioremediation, but lipase activity was on the contrary. The CAT activity was more sensible to the oil than others, and could be alternative to monitor the bioremediation process.

In this study, the single extraction and sequential extraction procedure were used to separate Pb from an old smelter soil in Liaoning Province, China. At the same time, the root and the overground parts of six species plants in the smelter were harvested for analysis. The concentrations of Pb in the roots and the overground parts of the plants were then compared with the amounts of Pb extracted from the rhizosphere soil by range of conventional extractants. The speciation distribution of Pb was RES > OX > OM > WSA > SE. Assuming that metal mobility and bioavailability are related to their solubility and the contents in typical plants in the contaminated soil, Pb would be the potential risk to environment safety in the area.

To evaluate the seasonal dynamics of phytoplankton and its relationships with aquatic habitat factors in polluted urban landscape lakes, annual investigations have been carried out in the West zone of Xinkai Lake. The results showed that the lake belongs to the eutrophic–supertrophic type in terms of key habitat factors measurement. The seasonal succession of phytoplankton community was determined. The dominant cyanobacterial species Oscillatoria tenuis Ag. bloomed in autumn, although the other species with higher degrees of dominance never bloomed in the year investigated. Significant correlations between some habitat factors and phytoplankton biomass were observed.