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Wastewater with high salinity is widely distributed, biological nitrogen removal process is inhibited by salt when it is used to treat wastewater containing high concentration of salt and ammonium. Nitrification is the key step of biological nitrogen removal process, thus researching the effect of salinity on nitrification is significant. In this article, the research progress of the impact of salinity on wastewater biological nitrification process was summarized. The influences of salinity stress on various aspects of nitrification process, including the efficiency of ammonia oxidation and nitrite oxidation processes, and the structure of aggregates, the characteristics of flocs and microbial community structure, were analyzed. The mechanism of nitrification process under high salinity was elaborated, providing a theoretical advice for designing biological nitrogen removal system of wastewater with high concentration of salt and ammonium. [ABSTRACT FROM AUTHOR]

Methane oxidation coupled to denitrification is an essential bond to connect carbon-and nitrogen cycling. To deeply research this process will improve our understanding on the biochemical cycling of global carbon and nitrogen. As an exogenous gaseous carbon source of denitrification, methane can both regulate the balance of atmospheric methane to effectively mitigate the greenhouse effect caused by methane, and reduce the cost of exogenous carbon source input in traditional wastewater denitrification treatment process. As a result, great attention has being paid to the mechanical study of the process. This paper mainly discussed the two types of methane oxidation coupled to denitrification, i. e. , aerobic methane oxidation coupled to denitrification (AME-D) and anaerobic methane oxidation coupled to denitrification (ANME-D), with the focus on the microbiological coupling mechanisms and related affecting factors. The existing problems in the engineering application of methane oxidation coupled to denitrification were pointed out, and the application prospects were approached. [ABSTRACT FROM AUTHOR]

Watershed water environment pollution model is the important tool for studying watershed environmental problems. Through the quantitative description of the complicated pollution processes of whole watershed system and its parts, the model can identify the main sources and migration pathways of pollutants, estimate the pollutant loadings, and evaluate their impacts on water environment, providing a basis for watershed planning and management. This paper reviewed the watershed water environment models widely applied at home and abroad, with the focuses on the models of pollutants loading (GWLF and PLOAD), water quality of received water bodies (QUAL2E and WASP), and the watershed models integrated pollutant loadings and water quality (HSPF, SWAT, AGNPS, AnnAGNPS, and SWMM), and introduced the structures, principles, and main characteristics as well as the limitations in practical applications of these models. The other models of water quality (CE-QUAL-W2, EFDC, and AQUATOX) and watershed models (GLEAMS and MIKE SHE) were also briefly introduced. Through the case analysis on the applications of single model and integrated models, the development trend and application prospect of the watershed water environment pollution models were discussed. [ABSTRACT FROM AUTHOR]

Biochar has its unique physical and chemical properties, playing a significant role in soil amelioration, nutrient retention, fertility improvement, and carbon storage, and being a hotspot in the research areas of soil ecosystem, biogeochemical cycling, and agricultural carbon sequestration. As a kind of anthropogenic materials, biochar has the potential in controlling soil nitrogen (N) cycle directly or indirectly, and thus, has profound effects on soil ecological functions. This paper reviewed the latest literatures regarding the effects of biochar applications on soil N cycle, with the focuses on the nitrogen species adsorption and the biochemical processes (nitrification, denitrification, and nitrogen fixation), and analyzed the related action mechanisms of biochar. The future research areas for better understanding the interactions between biochar and soil N cycle were proposed. [ABSTRACT FROM AUTHOR]

Aerobic composting is an effective way to treat and recycle livestock manure. However, the aerobic composting of livestock manure is a potential source of the greenhouse gas nitrous oxide (N2O), which closely relates to the global greenhouse effect and ozone depletion. With the expansion of livestock industry and the dramatic increasing yield of manure compost, the N2O emission during the aerobic composting has become a severe problem. The researches on the mechanisms of N2O emission during livestock manure composting have attracted increasing concerns. In this paper, the recent researches on the N2O generation approaches, emission dynamics, potential affecting factors, and microbiological mechanisms of N2O emission during livestock manure aerobic com- posting were reviewed, and the measures to control the N2O emission during composting process were summarized. Some perspectives for the future researches in this field were suggested. [ABSTRACT FROM AUTHOR]

Landfill is one of the main approaches for municipal solid waste treatment, and landfill site is a main emission source of greenhouse gases nitrous oxide (N2O) and methane (CH4). As a high-efficient trace greenhouse gas, N2O has a very high warming potential, with a warming capacity 296 times of CO2, and has a long-term stability in atmosphere, giving greater damage to the ozone layer. Aiming at the researches in the control of N2O emission from municipal solid waste landfill sites, this paper summarized the characteristics and related affecting factors of the N2O emission from the landfill sites, and put forward a series of the measures adaptable to the N2O emission control of present municipal solid waste landfill sites in China. Some further research focuses on the control of N2O emission from the landfill sites were also presented. [ABSTRACT FROM AUTHOR]

Anammox (anaerobic ammonium oxidation) is an important process of nitrogen cycle, with great potential for the practical use in removing nitrogen from the wastewater containing high concentration ammonium. However, the presence of high concentration organic carbon source is considered unfavorable to anammox. Coupling anammox and denitrification under the presence of organic carbon source could be a useful technique for removing both nitrogen and carbon. This pa- per reviewed the mechanisms of anammox-denitrification coupling process, functional microbial groups, initiation of the coupling process and its control, and related environmental affecting factors. The future research prospects and potential applications of anammox-denitrification coupling process in wastewater treatment were discussed. [ABSTRACT FROM AUTHOR]

Taking non-transgenic parental rice as the control, and by using 13C pulse-chase labeling method coupled with phospholipid fatty acid (PLFA) analysis, this paper studied the effects of transgenic Bt rice on the here soil. The results showed that in the rhizosphere soils of transgenic Bt rice and its non-transgenic parent, saturated PLFAs and branched PLFAs were the main, followed by monounsaturated PLFAs, and polyunsaturated PLFAs. A significantly lower amount of Gram-positive bacterial PLFAs and a higher amount of Gram-negative bacterial PLFAs were observed in the rhizosphere soil of transgenic Bt rice at its seedling, booting, and heading stages, as compared with the control. In the whole growth ?period of rice, transgenic Bt gene had no significant effects on the fungal and actinomycete PLFAs in rhizosphere soil, and no significant difference was observed in the rhizosphere soil 13C-PLFA content between transgenic Bt rice and its non-transgenic parent. These findings indicated that the insertion of exogenous cry1Ab gene into rice only had temporary effects on the microbial community composition in the rhizosphere soil of rice. [ABSTRACT FROM AUTHOR]

Methanogens play an important role in global carbon cycle. There exists a range of unknown methanogenic archaea in acidic peat lands, among which, acidophilic methanogens have attracted increasing research interests because of their special metabolic characteristics. To introduce acidophilic methanogens in the anaerobic digestion process of high concentration organic wastes or waste water could essentially overcome the inhibition of acid accumulation on the methanogens and help reduce the operation cost, broadening the industrial application of anaerobic bio-treatment technology. In this paper, we reviewed the recent researches on acidophilic methanogens, with the focus on enrichment and isolation methods, physiological and biochemical characters, metabolic characteristics, and application of molecular biology. The potential applications of acidophilic methanogens in anaerobic digestion process were analyzed and proposed, and the directions for further researches were suggested. [ABSTRACT FROM AUTHOR]

In-situ ammonium removal from municipal solid waste (MSW) landfill is an attractive method due to its economic advantages. In this study, two simulated MSW bioreactors with different degrees of initial bio-stabilization were utilized to investigate the effects of intermittent aeration mode and the addition of activated sludge on the removal of ammonium. The results showed that up to 90% of ammonium could be removed and the amount of NOx—N produced was less than 1% of NH4+-N removed in both reactors. The pH values increased rapidly and finally arrived at a high level of 8.5—8.8. The efficiency of ammonium removal was improved by increasing the continuous aeration time, but it was not affected by the addition of activated sludge. A portion of liquid escaped from the reactors in the form of vapour, and as high as 195—258 mg L—1 of NH4 +-N was detected in the vapour collector. According to calculation, nitrification was inhibited by the high level of free ammonia in the bioreactors. As a result, air stripping was enhanced and became the primary pathway of ammonium removal. Therefore, controlling free ammonia concentration was essential in ammonium removal from the aerated MSW bioreactor. [ABSTRACT FROM AUTHOR]

Landfill sites are the major sources of offensive odor in urban public facilities. With the progress of urbanization and the residents' demands for a higher living environment quality, the odor emission from landfill sites has become a severe pollution problem, and the odor control at landfill sites has been one of the research hotspots. This paper summarized the main components and their concentrations of the odor from landfill sites, and expatiated on the research progress in the in-situ control of the odor. The further research directions in in-situ control of the odor from landfill sites were prospected. [ABSTRACT FROM AUTHOR]

Composting is an effective way to realize livestock manure treatment and recycling. However, the nitrogen loss during manure composting is relatively serious. Studies on this nitrogen loss and its control could provide theoretic bas is and practical reference for efficient nitrogen loss control. This paper described the nitrogen transformation and the main nitrogen loss ways during the composting, and summarized the main factors (including raw material characteristics, environment factors, and technological conditions) affecting the nitrogen loss in the composting. In addition, the research progress in the nitrogen loss control, including adjusting carbon and nitrogen metabolism, changing nitrogen form, adding ammonia adsorbent, and controlling pile aeration and temperature, was reviewed, and the prospects for future research were presented. [ABSTRACT FROM AUTHOR]

Biomass-derived black carbon, also named biochar, has the characteristics of high stability against decay and high capability of adsorption, and can affect the environment through its interactions with climate and geology, playing a significant role in global climate change, carbon biogeochemical cycle, and environmental system. In recent years, more and more researchers in the fields of atmospheric sciences, geology, and environmental science focused on the environmental behavior and effect of biochar. As one possible source of the components with high aromatic structure in soil humus, biochar is of great importance in increasing soil carbon storage and improving soil fertility, and in maintaining the balance of soil ecosystem. This paper offered the latest information regarding the characteristics and biotic and abiotic oxidation mechanisms of biochar, its effects on global climate change, and the environmental effect of biochar in soil. Research prospects were briefly discussed on the environmental behavior and effect of biochar in soil ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the influences of the herbicide butachlor (n-butoxymethl-chloro-2′, 6′-diethylacetnilide) on microbial respiration, nitrogen fixation and nitrification, and on the activities of dehydrogenase and hydrogen peroxidase in paddy soil. The results showed that after application of butachlor with concentrations of 5.5 µg/g dried soil, 11.0 µg/g dried soil and 22.0 µg/g dried soil, the application of butachlor enhanced the activity of dehydrogenase at increasing concentrations. The soil dehydrogenase showed the highest activity on the 16th day after application of 22.0 µg/g dried soil of butachlor. The hydrogen peroxidase could be stimulated by butachlor. The soil respiration was depressed within a period from several days to more than 20 days, depending on concentrations of butachlor applied. Both the nitrogen fixation and nitrification were stimulated in the beginning but reduced greatly afterwards in paddy soil. [ABSTRACT FROM AUTHOR]

Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China.

Enhanced biological phosphorus removal (EBPR) process is applied widely for removing phosphorus from wastewater. Studies on functional microorganisms and their metabolic mechanisms are fundamental to effective regulation for stable operation and performance improvement of EBPR process. Two main types of microorganisms in EBPR systems, polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) were selected to summarize their metabolic mechanisms such as substrate uptake mechanisms, glycogen degradation pathways, extent of TCA cycle involvement and metabolic similarity between PAOs and GAOs. Application of molecular biology techniques in microbiology and metabolic mechanisms involved in the EBPR system was evaluated. Potential future research areas for the EBPR system and process optimization were also proposed.

In this paper, a treatment process consisted of UASB, step-fed sequencing batch reactor (SFSBR) and magnesium ammonium phosphate precipitation reactor (MAP) was built to treat the large scale swine wastewater, which aimed at overcoming drawbacks of conventional anaerobic-aerobic treatment process and SBR treatment process, such as the low denitrification efficiency, high operating costs and high nutrient losses and so on. Based on the treatment process, a pilot engineering was constructed. It was concluded from the experiment results that the removal efficiency of COD, NH4(+) -N and TP reached 95.1%, 92.7% and 88.8%, the recovery rate of NH4(+) -N and TP by MAP process reached 23.9% and 83.8%, the effluent quality was superior to the discharge standard of pollutants for livestock and poultry breeding (GB 18596-2001), mass concentration of COD, TN, NH4(+) -N, TP and SS were not higher than 135, 116, 43, 7.3 and 50 mg x L(-1) respectively. The process developed was reliable, kept self-balance of carbon source and alkalinity, reached high nutrient recovery efficiency. And the operating cost was equal to that of the traditional anaerobic-aerobic treatment process. So the treatment process could provide a high value of application and dissemination and be fit for the treatment pf the large scale swine wastewater in China.

There are plenty of methods used for the assessment of organic compounds biodegradability, but lack of comprehensive literatures in systematically introducing the assessment methods and guiding the choice of the methods. This paper briefly introduced the indicative parameters in assessing organic compounds biodegradability and the assessment methods of aerobic and anaerobic biodegradation, with the focus on the principles and criteria in the choice of the assessment methods, and analyzed in detail the reasons for the differences in the biodegradation rates of organic compounds when different test methods were adopted. Taking the standards established by the Organization for Economic Co-operation and Development (OECD) as an example, the process of choosing and applying the assessment methods was introduced, the systematic method-choosing route was integrated, and the advantages of the OECD standard methods were pointed out.

Landfill is one of the main approaches for municipal solid waste treatment, and landfill site is a main emission source of greenhouse gases nitrous oxide (N2O) and methane (CH4). As a high-efficient trace greenhouse gas, N2O has a very high warming potential, with a warming capacity 296 times of CO2, and has a long-term stability in atmosphere, giving greater damage to the ozone layer. Aiming at the researches in the control of N2O emission from municipal solid waste landfill sites, this paper summarized the characteristics and related affecting factors of the N2O emission from the landfill sites, and put forward a series of the measures adaptable to the N2O emission control of present municipal solid waste landfill sites in China. Some further research focuses on the control of N2O emission from the landfill sites were also presented.

The denitrification capacity of a landfill bioreactor was investigated under different ratios of injected leachate C/N; the denitrifying bacteria community compositions over four injection times were also studied using molecular approaches and functional gene nirS served as marker. Results showed that COD/NO3(-) -N ratio of the injected landfill leachate had a significant impact on the denitrification capacity of the bioreactor. Nitrate reduction rate increased from 1.14 mg x (kg x h)(-1) to 11.40 mg mg x (kg x h)(-1) when the injected leachate COD/NO3(-) -N ratio raised from 3.11 to 13.08. It suggested that a stable and rapid denitrification could be obtained when bioavailable COD/NO3(-) -N ratio in the injected leachate was 6.37. In the bioreactor, the main denitrifying bacteria was similar to beta-proteobacteria, and others belonged to uncultured bacteria. Thiobacillus denitrificans and Azoarcus tolulyticus known as beta-proteobacteria were the dominant species and played an important role in NO3(-) -N consumption during the leachate injection.

Objective: To investigate the relationship between chromosomal genomic DNA imbalance in medulloblastoma (MB), and the age and gender., Methods: The gains and losses of chromosomal genomic DNA in 16 MBs were analyzed using comparative genomic hybridization., Results: The gains and(or) losses were found in 15 of the 16 cases. There was not significant difference (P > 0.05) between the total gains (10/16) and losses (11/16). Both of their differences had also no significance between different age and gender groups (P > 0.05). In 15 cases with gains and(or) losses, single-, two-, three- and multi-chromosome genomic DNA imbalances were 3/15, 4/15, 1/15 and 7/15 respectively. Eleven gain zones (+5q, +6q, +7q, +11q, +15q, +17p, +17q, +19q, +20q, +21q, +Xp) and twenty-five loss zones (-1p, -1q, -2p, -2q, -3q, -4p, -6p, -6q, -8p, -8q, -10p, -10q, -11p, -14q, -16p, -16q, -17p, -18p, -18q, -19p, -19q, -20p, -20q, -Xp, -Xq) were detected in those tumors. +7q (6/16), +17q (6/16), -14q (5/16) and -10q (3/16) were the most frequent, but -14q only occurred in the cases of > 10-year-old., Conclusions: Most MBs have chromosomal genomic DNA imbalances. The frequent imbalance zones are mainly at the long arms of some chromosomes. +7q, +17q, -14q and -10q correlate closely to development of the tumors. -14q is important factor to result in MBs of > 10-year-old group. MB has possibly different molecular genetics subtype.

As the first step of nitrification, ammonia oxidation is the key process in global nitrogen biogeochemical cycling. So far, the autotrophic ammonia-oxidizing bacteria (AOB) in the beta- and gamma-subgroups of proteobacteria have been considered as the most important contributors to ammonia oxidation, but the recent researches indicated that ammonia-oxidizing archaea (AOA) are widely distributed in various kinds of ecosystems and quantitatively predominant, playing important roles in the global nitrogen biogeochemical cycling. This paper reviewed the morphological, physiological, and ecological characteristics and the molecular phylogenies of AOA, and compared and analyzed the differences and similarities of the ammonia monooxygenase (AMO) and its encoding genes between AOA and AOB. In addition, the potential significant roles of AOA in nitrogen biogeochemical cycling in aquatic and terrestrial ecosystems were summarized, and the future research directions of AOA in applied ecology and environmental protection were put forward.

Periphyton widely exists in natural water bodies, with the characteristics of huge biomass generation, strong ecological function, and sensitive response to water quality. It removes the pollutants in water bodies mainly through the processes of absorption, metabolism, adsorption, and complexation, etc. Owing to its high tolerance against pollution and high removal efficiency for nitrogen and phosphorus, as well as the feasibility of recycling its cells at low cost, periphyton is a promising candidate for developing the treatment techniques of water purification. The newly-developed artificial periphyton systems, e.g., algal turf scrubbers, periphyton biofilm systems, periphyton aquaculture systems, have been successfully applied in treating livestock manure, aquaculture wastewater, and municipal sewage. However, further researches are needed to understand the growth patterns of periphyton, its physiological responses to pollutants concentration, and its molecular biological mechanisms in removing pollutants.

The effects of bio-charcoal acted as sludge-composting additive on soil characteristics and plant growth were studied. Compared with the treatment of composted sludge without bio-charcoal, soil cation exchange capacity in treatment of composted sludge with bio-charcoal increased over 5% and 10% respectively and soil nitrogen content increased 13% and 18% respectively for two kind soils. The composted sludge with bio-charcoal also resulted in 23% higher enhancement on ryegrass biomass and 8%-10% higher enhancement on ryegrass chlorophyll content. In addition, with the amendment of bio-charcoal, the bioavailability of polycyclic aromatic hydrocarbons (PAHs) in composted sludge was decreased, which resulted in the lower absorption and accumulation of ryegrass to PAHs. Compared with the control, the PAHs concentration in ryegrass amended composted sludge with bio-charcoal decreased 27%-34%. The results indicated that composted sludge with bio-charcoal resulted in much more improvement on the plant growth as well as less negative effect on environment. Therefore, biocharcoal was in favor of the safe land application of sewage sludge.

Objective: To investigate genomic DNA imbalances in ependymomas (EDMs) and their correlations with the tumor histological types, grades, locations, patients' gender and age., Methods: Chromosomal gains and losses in 16 cases of EDM were analyzed using comparative genomic hybridization., Results: Chromosomal regional gain and loss were found in 15 and 13 of 16 EDM cases respectively including totally 24 regional gains and 19 regional losses in all the tumors studied. Both regional gains and losses were mostly seen in myxopapillary EDMs (MPE, WHO grade I), more commonly seen in cellular EDMs (CE, WHO grade II) and tanycytic EDMs (TE, WHO grade II) than in anaplastic EDMs (AE, WHO grade III). Some of the regional gains and losses appeared only in one subtype of MPE, CE, TE and AE cases resulting in development of specific imbalance profiles of certain subtype in these cases. MPE, CE and TE often had +7. Chromosomal +5 occurred only in MPE and CE, and -22q was only seen in CE and TE. AE frequently had +1q, but none had +5, +7, -4q, -19q and -22q. The frequencies of any regional gain or loss were not affected by patients' genders (P > 0.05). Chromosomal +1q and +7p happened predominantly in intracranial EDMs with an averagely onset age of

As a main life element, carbon plays important role in the matter cycling in soil-plant system. Stable carbon isotope 13C has been widely used in the study of carbon cycling in soil-plant system, due to its safe, no pollution, and easy to be handled. Through the analysis of both natural and labeled 13C organic matter in soil-plant system, a better understanding of the mechanisms of photosynthesis, the distribution of photosynthates in plant-soil system, the fate of plant litter, and the source of new carbon in soil could be achieved. In this paper, the applications of stable carbon isotope technique in the researches of photosynthesis, reconstruction of paleoclimate, turnover of soil organic matter, and interactions between plants and rhizosphere microorganisms were briefly summarized, and the perspectives of the application of stable carbon isotope technique were also discussed, based on the issues existed in current researches.