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Root Zone microbial populations, Urease Activities, and Purification Efficiency for a Constructed Wetland

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Pedosphere 2004年第3期14卷 401-404页

作者： LIANGWei WUZhen-Bin ZHANFa-Cui DENGJia-Qi EnvironmentSimulationandPollutionControlStateKeyJointLaboratory DepartmentofEnvironmentalScienceandEngineeringTsinghuaUniversityBeijing100084（China） StateKeyLaboratoryofFreshwaterEcologyandBiotechnology InstituteofHydrobiologyChineseAcademyofSciencesWuhan430072（China）

In order to investigate the effects of microorganisms and their urease activities in macrophytic root zones on pollutant removal, four small-scale plots (SSPs) of vertical/reverse-vertical flow wetlands were set up to determine: a) the relationship between the abundance of microorganisms in the root zones and water purification efficiency; and b) the relationship between urease activities in the root zones and pollutant removal in a constructed wetland system. Total numbers of the microbial population (bacteria, fungi, and actinomyces) along with urease activities in the macrophytic root zones were determined. In addition, the relationships between microbial populations and urease activities as well as the wastewater purification efficiencies of total phosphorus (TP), total Kjeldahl nitrogen (TKN), biochemical oxygen demand in 5 days (BOD5), and chemical oxygen demand (COD) were also analyzed. The results showed that there was a highly significant positive correlation (r = 0.9772, P ＜ 0.01) between the number of bacteria in the root zones and BOD5 removal efficiency and a significant negative correlation (r = -0.9092, P ＜ 0.05) between the number of fungi and the removal efficiency of TKN. Meanwhile, there was a significant positive correlation (r -- 0.8830, P ＜ 0.05) between urease activities in the root zones and the removal efficiency of TKN. Thus, during wastewater treatment in a constructed wetland system,microorganism and urease activities in the root zones were very important factors.

关键词： macrophytic root zone microbial population purification efficiency ureaseactivity wetland

Effect of probiotics on growth performance, development of small intestinal tract and microbial populations in broilers

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Journal of Agricultural Science and Technology 2009年第4期3卷 24-31,39页

作者： LEI Yan ZHANG Ke-ying DING Xue-mei BAI Shi-ping JUNG Sik Choi Animal Nutrition Institute Sichuan Agricultural University Ya ＇an 625014 China Engineering Research Center of Animal Disease-Resistance Nutrition of China Ministry of Education Sichuan Agricultural University Ya ＇an 625014 China JSC Bio-teek Company Korea 4490205 Korea

The experiment was conducted using a total of 1392 one-day-old, Cobb commercial male broilers to investigate the effects of a commercial probiotic addition in diet on growth, the development of the small intestine and microbial populations of broilers. Broilers were randomly allotted by BW to 1 of 6 replicate cages （29 chicks per cage） for each of 8 treatments in a randomized block design involving one factorial arrangement of treatments. Dietary treatments included the basal diet （including corn, soybean, rapeseed, cottonseed meal） added with 100 mg/kg antibiotic, 0%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25% or 0.3%. The experiment last 42 d and divided into the starter period （1-21 d） and the finisher period （22-42 d）. The results showed that there were significant differences in broiler body weight （BW）（P〈0.001）, average daily feed intake （ADFI）（P=0.033）, relative length of the duodenum （P〈0.001）, jejunum （P=0.008）, ileum （P〈0.001） and the populations of lactobacillus （P〈0.001） and coliform （P〈0.001） in the rectum between the probiotics treatments and the control treatment only in the starter period of the trails. No significant differences were observed in intestinal morphology parameters in two periods of the experiment. Our results indicated that the probiotic was able to improve the performance of broiler chickens, and it was better in the starter period to be used than in the finisher period.

关键词： probiotic broiler chickens performance intestine development microbial population

Degradation of crude oil by indigenous microorganisms supplemented with nutrients

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Journal of Environmental Sciences 2005年第4期17卷 659-661页

作者： XIAWen-xiang ZHENGXi-lai LIJin-cheng SONGZhi-wen SUNHao-fen DepartmentofEnvironmentalEngineering OceanUniversityofChinaQingdao266003China DepartmentofEnvironmentalEngineering QingdaoTechnologicalUniversityQingdao266033China DepartmentofEnvironmentalEngineering OceanUniversityofChinaQingdao266003China／／DepartmentofEnvironmentalEngineeringQingdaoTechnologicalUniversityQingdao266033China

Different kinds of mineral nutrients(NO_3-N, NH_4-N and PO_4-P) were applied in the simulated oil-polluted seawater for enhancing oil biodegradation in the N/P ratio 10∶1 and 20:1 Although indigenous microorganisms have the ability to degrade oil, adding nutrients accelerated biodegradation rates significantly. For the group amended with NO_3-N and PO_4-P in the ratio 10∶1, the reaction rate coefficient was 4 times higher than the natural biodegradation. Chemical and microbiological analysis showed that the optimal N/P ratio in the system is 10∶1, and microorganisms tend to utilize nitrate rather than ammonium as N source.

关键词： oil spill biodegradation kinetics N/P ratio microbial population

Resistance and resilience of soil biological indicators:A case study with multi-walled carbon nanotube

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Pedosphere 2024年第3期34卷 664-675页

作者： Shagufta YASMEEN Nintu MANDAL Anupam DAS Pritam GANGULY Sanjay KUMAR Rajiv RAKSHIT Department of Soil Science and Agricultural Chemistry Bihar Agricultural UniversitySabourBhagalpur 813210(India) Department of Agronomy Bihar Agricultural UniversitySabourBhagalpur 813210(India)

Soil ecosystem is experiencing stresses due to climate change,and soil inhabitants try to demonstrate their inherent resistance and resilience against those *** of nanomaterials as agricultural inputs could bring shifts in resistance and resilience patterns of soil microbes and associated enzymes,especially under short-term heat *** this background,the impacts of multi-walled carbon nanotube(MWCNT)on the resistance and resilience of soil biological indicators were *** incubation experiment was conducted with varied MWCNT concentrations(0,50,100,250,and 500 mg kg-1soil)for 90 d after 24-h heat stress at 48±2?C to assess the impacts of MWCNT on soil enzyme activities and microbial populations vis-à-vis their resistance and resilience indices under short-term exposure to heat *** activities were reduced after exposure to heat *** indices of enzyme activities were enhanced by MWCNT application on day 1 after heat stress,whereas there was no recovery of enzyme activities after 90-d *** soil enzyme activities,resistance index values of soil microbial populations followed the similar trend and were improved by MWCNT ***-walled carbon nanotube has the potential to improve resistance indices of soil enzyme activities and microbial populations under heat stress,although they could not recover to their original state during periodical incubation after heat *** study helps to understand the relative changes of biological indicators under MWCNT and their ability to withstand heat stress.

关键词： enzyme activity heat stress microbial population nanomaterial recovery

Characteristic analysis of phospholipid fatty acids(PLFAs) in typical nutrient polluted lake sediment in Wuhan

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International Journal of Sediment Research 2021年第2期36卷 221-228页

作者： Xia Zhang Qianru Chen Chuan Wang Hongpei Zhang Yuqing Zhao Liping Zhang Biyun Liu Zhenbin Wu Qiaohong Zhou College of Resources and Environmental Engineering Wuhan University of Technology State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences

The process of urbanization aggravates the endogenous pollution of urban lake sediment, and polluted sediment may seriously affect the quality of the water in lakes. At present, it is difficult to distinguish the difference between sediment that is heavily polluted by nitrogen(N) and phosphorus(P) when using an analysis based on a physicochemical index classification. The current study applied phospholipid fatty acid(PLFA) technology to further analyze the sediment characteristics from the perspective of microbiology. Surface sediment from five urban lakes that are heavily polluted with N and P in Wuhan were sampled. Statistical approaches were used to analyze the microbial community structure in the sampled sediment, and to determine the correlations between the microorganisms and physicochemical *** most severely polluted lake sediment had similar PLFA structures, the highest saturated fatty-acid content, and bacteria as the dominant microorganism. However, there were differences between the microbial biomass of the various sediment samples, which may have been related to the degree of N and P pollution. Analysis of the microbial diversity in the sediment samples indicated that the bacteria were experiencing starvation and nutrient pressure, which may have been due to the dissolved oxygen concentration of the heavily polluted lake sediment. A correlation analysis showed that the endogenous N and P had different effects on the microbes of the polluted sediment. A redundancy analysis(RDA)demonstrated that the N/P ratio had the greatest influence on the PLFA species, accounting for 83% of the cumulative interpretation. To effectively promote the role of sediment microorganisms on circulating elements, it is necessary to regulate the N/P ratio of the sediment to some extent. When the N/P ratio in sediment exceeds 6, N pollution should be prioritized.

关键词： Lake sediment Endogenous pollution Phospholipid fatty acid (PLFA) analysis microbial population N/P ratio

Ruminal fermentation and microbial community differently influenced by four typical subtropical forages in vitro

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Animal Nutrition 2018年第1期4卷 100-108页

作者： Muhammad W.Iqbal Qin Zhang Yingbai Yang Caixia Zou Lili Li Xin Liang Shengju Wei Bo Lin College of Animal Science Guangxi University Buffalo Research Institute The Chinese Academy of Agricultural Sciences

The present study evaluated the effects of 4 typical subtropical forages on ruminal microbial community composition to formulate a better diet for *** straw silage,elephant grass,cassava residues and sugarcane tail silage were used as substrates for in vitro *** replicates were set up for every substrate,and fermentation was carried out in a 100-m L glass syringe,using buffalo rumen *** replicate was anaerobically dispensed with 10 m L of rumen inoculum,20 m L of Mc Dougall's buffer and 200 mg of dried substrate,and placed in a water bath at *** production was recorded at 0,2,6,12,24,36,48 and 72 h of *** 24 h,fermentation was ceased for 4 replicates and samples were *** fatty acids(VFA) concentrations were measured using gas *** populations were quantified using quantitative real-time PCR(q RT-PCR),and microbial community was analyzed using high throughput sequencing *** results showed,cassava residues as substrate had the highest gas production,acetate,propionate and total VFA concentrations(P microbial *** conclusion,incubation with cassava residues resulted in lower number of fiber degrading microbes but higher protozoal

关键词： Buffalo rumen inoculum In vitro fermentation Subtropical forages microbial population microbial community

Reduction of Nitrate to Ammonium in Selected Paddy Soils of China *1

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Pedosphere 1998年第3期8卷 221-228页

作者： YINSHIXUE SHENQIRONG 等 DepartmentofAgronomy AgriculturalCollegeYangzhouUniversityYangzhou225009（China） CollegeofResourcesa

Three paddy soils were examined for their capacities of dissimilatory reduction of nitrate to ammonium (DRNA). 15 N labelled KNO 3 was added at the rate of 100 mg N kg -1 . Either glucose or rice straw powder was incorporated at the rate of 1.0 or 2.0 mg C kg -1 respectively. Three treatments were designed to keep the soil saturated with water: A) a 2 cm water layer on soil surface (with beaker mouth open); B) a 2 cm water layer and a 1 cm liquid paraffin layer (with beaker mouth open); and C) water saturated under O 2 free Ar atmosphere. The soils were incubated at 28 oC for 5 days. There was almost no 15 N labelled NH + 4 N detected in Treatment A. However, there was 1.4 to 3.4 mg N kg -1 15 N labelled NH + 4 N in Treatment B and 2.1 to 13.8 mg N kg -1 in Treatment C. Glucose was more effective than straw powder in ammonium production. Because there was sufficient amount of non labelled NH + 4 N in the original soils, 15 N labelled NH + 4 N produced as such should be the result of dissimilatory reduction. Studies on microbial population showed that there were plenty of bacteria responsible for DRNA process (DRNA bacteria) in the soils examined, indicating that number of DRNA bacteria was not a limiting factor for ammonium production. However, DRNA bacteria were inferior in number to denitrifiers. DRNA process in soil suspension seemed to start after 5 days of incubation. Glycerol and sodium succinate, though both are readily available carbon sources to organisms,did not facilitate DRNA process. DRNA occurred only when glucose was available and at the C/NO 3 - N ratio of over 12. It seemed that both availability and quality of the carbon sources affected DRNA.

关键词： carbon source dissimilatory reduction of nitrate to ammonium microbial population

Heavy metal contamination, physico-chemical and microbial evaluation of water samples collected from chromite mine environment of Sukinda, India

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Transactions of Nonferrous Metals Society of China 2013年第2期23卷 484-493页

作者： S. DAS S. C. PATNAIK H. K. SAHU A. CHAKRABORTY M. SUDARSHAN H. N. THATOI Department of Biotechnology College of Engineering and Technology Biju Patnaik University of Technology Bhubaneswar Odisha-751003 India Department of Zoology North Orissa University Baripada Odisha-757003 India University Grants Commission-Department of Atomic Energy Center for Scientific Research Kolkata Centre Bidhan Nagar Kolkata West Bengal-700098 India

Water samples from chromite mine quarry of Sukinda and its adjacent areas were analyzed for their heavy metal contamination along with physico-chemical and microbial contents. The chromite mine water samples possessed high concentrations of heavy metals in the order of Cr〉Fe〉Zn〉Ni〉Co〉Mn while ground water did not show any heavy metal contamination except Fe. Physico-chemical parameters of mine water samples showed deviation from those of normal water. Mine water harboured low microbial populations of bacteria, fungi and actinomycetes in comparison with mine adjacent water samples. The correlation of data between metals with physico-chemical parameters showed both positive and negative responses while that of metal and microbial population exhibited negative correlation. Bacterial strains isolated from chromite mine water exhibited high tolerance towards chromium and other heavy metals as well as antibiotics which could be used as an indicator of heavy metal pollution.

关键词： bioremediation hexavalent chromium physico-chemical properties mine water pollution microbial population chromium tolerant bacteria

System of Rice Intensification Verses Conventional Rice System: Off-farm Field Studies

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NASS Journal of Agricultural Sciences 2019年第1期1卷 7-17页

作者： Ravi Chandra Sharma Nobuhiko Fuwa Pabitra Banik R esearch and Development Division Rashtriya Chemicals and Fertilizer LimitedMumbai 400074 University of Tokyo Japan Agricultural and Ecological Research Unit Indian Statistical InstituteKolkata 700103

With inevitable growth of demand for human and industrial needs,water available for agriculture will become scarcer in the *** is a highly water-stressed ***,India needs to invest in improving its water productivity,and any capacity to produce more rice with less *** of Rice Intensification(SRI)has attracted much attention in increasing rice yield per unit *** this study,fifteen farmers were selected those were practicing SRI technology by themselves during the Boro-cultivation season(January-April).The study was continued for three consecutive years 2012 to 14 on the same *** addition to the SRI plots,a similar size of non-SRI plot was maintained in conventional cultivation for comparison *** an average,the non-SR I ight increased by 12%,number of tillers per square meter by 85%,number of reproductive tillers per hill by 286%,weight of panicle per hill by 139%,number of seeds per panicle by 41%and test weight by 26% due to SRI practice over the non-SRI *** increment in straw and grain yield due to SRI over the non-SRI is 70%and 59%*** physico-chemical and biological properties of soil improved due to SRI practice.

关键词： System of rice intensification(SRI) Rice productivity microbial population Soil properties