Papers by Author: Fang Ma

Abstract: Riparian buffer zones (RBZ) plays important roles in the quality of surface water, the width and the connection of RBZ are related with the pollution removal effect. This paper evaluates the RBZ conditions in the basin of Xiquanyan reservoir which is an alternative drinking water supply reservoir. Using the software of ENVI to extract the RBZ distribution map from the image of Landsat 8; GIS and Fragstats were used to evaluate the status of RBZ. Divide the basin of Xiquanyan reservoir in to four divisions. The river lengthy, areas, average width of RBZ, SD, AI, and CONTAG were identified in each division. The result shows: (1) The total area of RBZ in the basin of Xiquanyan reservoir is adequate; however, the distribution of RBZ is uneven, part of it is too large, part of it is too small; (2) the connection of RBZ is good in part of the basin, it needs to improve the quality in the fourth division, western part of the Xiquanyan reservoir.

Abstract: Many factors can impact water quality, such as rainfall, topography and soil. These factors are usually naturally formed. In these factors, Land-Use is closely related with human production and living which people can change. It is one of the most key factors influencing the river water quality. With the development of computer technology, it is an important direction of researching Land-Use and Land-Cover Change (LUCC) in the application of water quality modeling. This paper analyzes the relationship between land-use change and the water quality, and introduces the common used water quality model.

Abstract: Soil respiration can be altered by changing substance supply, respiratory capacity and the demand for the products. We carried out a field experiment in the northeast of China to understand how inoculation with arbuscular mycorrhizal fungi (AMF) alters soil respiration in paddy fields. Soil respiration and factors contributing to it were measured for paddy fields either inoculated or non-inoculated with AMF, with or without fertilization. We found that inoculation increased soil respiration, net photosynthesis of rice leaves, N and P content of rice shoots and the abundance of actinomyces and fungi in rhizosphere; while the negative effect was only observed on root biomass. We also found that fertilization decreased the responses of soil respiration, root biomass and the abundance of bacteria and fungi in rhizosphere to inoculation. However, it decreased the responses of net photosynthesis, shoot biomass and shoot N and P content to inoculation. Conclusively, AMF inoculation promoted soil respiration by enhancing substrate supply, respiratory capacity and the demand for products; while the impacts of inoculation were weakened by fertilization via respiration capacity and the demand for the products.

Abstract: The Soil and Water Assessment Tool (SWAT) model was examined for its applicability in modeling stream-flow and nutrients (total nitrogen, TN and total phosphorus, TP) in Ashi River Basin, China covering an area of 3545 km². This model was calibrated by using the observed data of monthly flow during 1996-2005 and nutrients (TN and TP) during 2006-2008, and validated by using the observed data of monthly flow during 2006-2010 and water quality during 2009-2010. For stream-flow, the monthly results of RE, R² and E_NS values reached 6.42%, 0.61 and 0.59 respectively for calibration period, whereas these were-12.83%, 0.69 and 0.67, respectively for validation period; for TN calibration, values of RE, R² and E_NS were-18.33%, 0.64 and 0.55 respectively, and for validation period they were-17.34%, 0.68 and 0.57 respectively; for TP calibration, values of RE, R² and E_NS were-4.32%, 0.61 and 0.56 respectively, and for validation period they were-18.02%, 0.67 and 0.58 respectively. Results show that SWAT has applicability in modeling stream-flow and nutrients (TN and TP) in cold and flat area.

Abstract: Aerobic denitrification process is attracted more attention to enhance nitrogen removal technology. Aerobic denitrifying bacteria present excelled abilities with fast growth rate and denitrifying speed, though they are not dominant in most practical processes. A high-efficiency strain was enriched in SBR from aerobic activated sludge by the way of intermittent aeration and continuous aeration combination. The strain was determined to Pseudomonas stutzeri T13 with ability of TN removal 90% and nitrate removal 97%. The limiting factors for aerobic denitrifying efficiency were optimized to temperature=31°C,pH=7.11 and DO=2.5 mg/L using response surface methodology. A total of 32 genes are related to nitrogen removal in strain T13. And 10 related to nitrate reductase, especially including 3 genes encoding the periplasmic nitrate reductase, playing important role to aerobic denitrification. It gave good understanding to supply effective technological supports for aerobic denitrification process.

Abstract: Taking the marsh meadow Deyeuxia angustifolia in San Jiang Plain of Northeast China as test material,a field experiment was carried out with treatments different in nitrogen supply (0,4,8g/m²) to investigate the effects the soil nutrient content.The results showed that difference among layers soil organic matter activity firstly increased and then decreased with increasing of nitrogen addition. Difference among layers soil total nitrogen contains were no significant differences. Soil total nitrogen contains reduced gradually in the 0-10cm layers,in the 10-20cm and 20-30cm layers firstly increased and then decreased. Difference among layers soil ammonium N contains were no significant differences.The 0-10cm and 20-30cm layers soil total NO_-³-N firstly increased and then decreased,10-20cm layers firstly decreased and then increased. Difference among layers soil nitrate N contains obviously different levels (p<0.05). With increasing of nitrogen addition, the 0-10cm and 10-20cm layers soil total phosphoru contains increased gradually,20-30cm layers firstly increased and then decreased. With increasing of nitrogen addition,difference among layers soil total potassium contains were no significant differences.

Abstract: The performance of anaerobic digesters was inhibited intensively by low temperature anaerobic digestion. In this study, a group of psychrophilic methanogenic community was isolated from psychrophilic environment, sediment of Crane Lake. The massively parallel sequencing technology, 454 pyrosequencing technique, was adopted to analyze bacterial community, with dominant phyla belonging to Firmicutes (78.64% of total bacteria), Bacteroidetes (7.97%) and Chloroflexi (3.91%). Methanobacteria sp. and Methanomicrobia sp. were detected by clone library technique. After 6 enrichment culture generations, cumulative biogas production and methane concentration achieved 195 ml and 57.4%, respectively. The optimum performance of enrichment psychrophiles exhibited at a temperature of 18 °C, and maximum voluminal biogas production was 0.26 m³ m³_reactor d^-1. The study also investigated the biomethane conversion of enrichment psychrophiles utilizing acidified cattle dung as substrate. After 11 days of operation, the maximum biogas production and methane concentration achieved 48 ml d^-1 and 51.6%, respectively.

Abstract: Ionic liquids (ILs) are one class of important industrial chemicals that may replace conventional organic solvents. Due to the solubility, the toxicity study of ILs focused on aquatic mediums. However, there is seldom research for the the toxicity on terrestrial organism. In this paper, we studied the toxicity of three imidazolium ionic liquids 1-butyl-3-methyl imidazolium chloride ([Bmim][CL]), 1-butyl-3-methyl imidazolium tetrafluoroborate ([Bmim][BF₄]), and 1-butyl-3-methyl imidazolium trifluoroacetate ([Bmim][CF₃COOH]) on seed germination and seedling growth of pakchoi. Inter-simple sequence repeat (ISSR) marker technique was applied to detect DNA damage induced by imidazolium ILs. The results showed that all of three ILs could inhibit seed germination and seedling growth of pakchoi significantly at higher concentration (≥16 mM/L). At same concentration (1 mM/L and 4 mM/L), the genotoxicity of three ILs was following the trends: [Bmim][BF₄]> [Bmim][CF₃COOH]> [Bmim][CL]. It was concluded that ISSR assay offered a useful way to detect toxicity of ILs contamination on plant at low concentration even without transformation of physiological feature, such as germination and growth parameters and so on.

Abstract: This work focused on the advanced treatment of the secondary treated ethylene chemical plant effluent, which contained high conductivity and high organic concentration. To reduce the cost and improve operation stability, a biological aerated filter-ultrafiltration-reverse osmosis (BAF-UF-RO) process was proposed. The feasibility and effectiveness of the BAF loaded with a novel non-sintered fly-ash ceramsite (NSFC) as pretreatment method were investigated in detail. The results showed that the COD, turbidity, NH₃-N and SDI₁₅ in the effluent from the BAF were reduced largely. The BAF-UF-RO process was stable with the recovery rate of 75%, and the desalination rate was up to about 97.5%. Moreover, the operating pressure and backwash frequency of RO maintained 0.94-0.98 MPa and 2 times/d, respectively. After continuous operation for four months, there appeared to be no need for chemical cleaning of the RO membrane.

Abstract: So far, the study on diversity of microbial community which produces flocculating substances is relatively few. In this paper, soil, activated sludge and wastewater samples are collected from 21 different places, and then are cultivated in 5 different media. 5 different colony groups form large amounts of slime externally, which having high level of flocculation activities. Biolog is used to analysis the functional diversity of microbial communities.The microbial community BF-BCT having highest flocculating capability. The AWCD analysis results shows that the micro be in the BF-BCT utilized more carbons compared with the other six colony groups. In addition, the diversity analysis has similar conclusions with PCA analysis.