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Effects of Nitrogen Fertilizer on Rhizosphere Microbial Populations under Cotton Intercropped with Red Date in Arid Desert Oasis of Southern Xinjiang
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作者 汤秋香 石大伟 +7 位作者 林涛 高文伟 田立文 郭仁松 李玉 叶强涛 林毅 徐海东 《Agricultural Science & Technology》 CAS 2014年第2期207-211,309,共6页
[Objective]This study aimed to determine the number of microorganisms of cotton rhizosphere in a soil at various amounts of applied nitrogen fertilizer in a red date-cotton intercropping system. [Method] In the field ... [Objective]This study aimed to determine the number of microorganisms of cotton rhizosphere in a soil at various amounts of applied nitrogen fertilizer in a red date-cotton intercropping system. [Method] In the field experiment, nitrogen fer-tilizer was applied at 0, 150, 300, 450, 600, and 750 kg/hm2, respectively. The dy-namic changes of the populations of bacteria, fungi and actinomycetes at the rhizo-sphere of cotton intercropped with red date were investigated. [Result] Microbial populations significantly increased at nitrogen fertilizer of 300 and 450 kg/hm2 during bud, flowering and bol opening periods. The numbers of bacteria and actinomycetes were higher during flowering and bol opening stages than at bud stage. The num-ber of fungi slightly changed during the entire growth period. Appropriate amount of nitrogen fertilizer (300 to 600 kg/hm2) was favorable to the survival of the microor-ganisms in the soil under the intercropping system. [Conclusion] The study provides a guideline for screening and determining the optimum amount of applied nitrogen fertilizer. 展开更多
关键词 Red date and cotton intercropping system Nitrogen fertilizer Rhizo-sphere soil microbial populations
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Dynamic Study of Microbial Population and Enzyme Activity in Rhizosphere Soil of Allium sativum L.
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作者 周艳丽 王艳 +1 位作者 李金英 薛艳杰 《Agricultural Science & Technology》 CAS 2010年第9期140-143,共4页
[Objective] The aim was to investigate the changes in microbial population and soil enzyme activities in rhizosphere soil of two cultivars of Allium sativum L.at different growth stages.[Method]By using white garlic a... [Objective] The aim was to investigate the changes in microbial population and soil enzyme activities in rhizosphere soil of two cultivars of Allium sativum L.at different growth stages.[Method]By using white garlic and purple garlic as the experimental materials,the microbial population,and the activities of urease,acid phosphatase and catalase in their rhizosphere soil at different growth stages were measured.[Result]The root exudates of the two garlic cultivars could promote the growth of bacteria,fungi and actinomycetes,and indirectly increase the urease,acid phosphatase and catalase activities in the rhizosphere soil,thereby improving the turnover and circulation of the soil nutrition elements such as nitrogen and phosphorus,and providing a better micro-ecological environment for the later crop.[Conclusion]The study had provided theoretical basis for the ecological research on garlic used as a preceding crop. 展开更多
关键词 Allium sativum L. Soil microbial population Soil enzyme
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Combined Effect of Nutrient and Pest Managements on Substrate Utilization Pattern of Soil Microbial Population in Hybrid Rice Cropping System 被引量:9
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作者 LIAOMIN S.KLOSE 《Pedosphere》 SCIE CAS CSCD 2002年第3期219-228,共10页
A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populati... A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populations in hybrid rice cropping system. The mineral N, Pand K fertilizers (as urea, calcium superphosphate and KCl respectively) were incorporated at 100,25, and 100 kg ha^(-1), respectively, and the various pesticides were applied at the recommendedrates. The results of the experiment demonstrated a decline in the microbial abundance and soilmicrobial biomass phospholipid contents with the advancement of crop growth, and significant changesin substrate utilization pattern of soil microbial population studied were observed with differentmanagement practices and at different growth stages. The principal component analysis (PCA) usingall 95-carbon sources (BIOLOG plates) gave good differentiation among the treatments, indicatingthat they have different patterns of carbon utilization under different habitats. The data showedthat diversity in microbial community continuously changed with the progression in crop stage,particularly at physiological maturity (PM) stage that was evident from the utilization of differentcarbon sources at various crop stages. 展开更多
关键词 BIOLOG NUTRIENT pest management soil microbial population substrateutilization pattern
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Root Zone Microbial Populations, Urease Activities, and Purification Efficiency for a Constructed Wetland 被引量:7
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作者 LIANGWei WUZhen-Bin +1 位作者 ZHANFa-Cui DENGJia-Qi 《Pedosphere》 SCIE CAS CSCD 2004年第3期401-404,共4页
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... 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. 展开更多
关键词 macrophytic root zone microbial population purification efficiency ureaseactivity WETLAND
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Characteristics of the soil microbial population in forest land irrigated with saline water in the desert area 被引量:2
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作者 Jin, ZhengZhong Lei, JiaQiang +3 位作者 Xu, XinWen Li, ShengYu Fan, JingLong Zhao, SiFeng 《Journal of Arid Land》 SCIE 2010年第2期107-115,共9页
The study of soil microbial populations and diversity is an important way to understanding the soil energy process.In this study we analyzed the characteristics of soil microbial populations of the Tarim Desert Highwa... The study of soil microbial populations and diversity is an important way to understanding the soil energy process.In this study we analyzed the characteristics of soil microbial populations of the Tarim Desert Highway shelter-forest,by identifying microbial fatty acids and using methods of conventional cul-tivation.The results illustrated that the amount of soil microbial activity and the diversity of soil microbial fatty acid increased significantly with the plantation age of the shelter-forest;the soil microbial population was dominated by bacteria.The fatty acids of C14︰0,C15︰0,C16︰0,C17︰0,C18︰1ω9,C18︰0,C18︰2ω6 and C21︰0 were found to be dominant soil microbial fatty acids in the shelter-forest soil.Prin-cipal analysis and regression analysis showed that(1) concentrations of fatty acids of C14︰0,C16︰0 and C18︰0 could be used as indicators of total soil microbial population;(2) soil bacteria and actinomycetes populations were closely correlated with the amount of fatty acids of C15︰0 and C17︰0;and(3) soil fungi were closely correlated with the amount of fatty acids of C18︰1ω9 and C18︰2ω6. 展开更多
关键词 DESERT shelter forest soil microbial population phospholipids fatty acid
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Effect of Lanthanum on Major Microbial Populations in Red Soil 被引量:1
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作者 CHU HAIYAN, WANG JUNHUA, XIE ZUBIN, ZHU JIANGUO, LI ZHENGAO and CAO ZHIHONG (Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China)) 《Pedosphere》 SCIE CAS CSCD 2001年第1期73-76,共4页
Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacter... Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacteria, in a red soil taken form the Ecological Experimental Station of Red Soil, the Chinese Academy of Sciences, Jiangxi Province. LaCl3 was added into media at levels of 0, 25, 50, 100, 150, 200, 250 and 500 mg L-1 in the pure culture experiment, and into soil samples in porcelain pots before rice growing at levels of 0, 6, 30, 150, 300, 600 and 900 mg kg-1 dry soil in the pot culture experiment. The populations of the three soil microbes in the pure culture experiment decreased with the addition level of La, indicating that La was toxic to the soil microbes in pure culture, and the sensitivity of the 3 major microbial types to La was in a decreasing order of actinomyces > bacteria > fungus. In the pot experiment, La had slightly stimulative effect on soil bacteria and actinomyces when applied at low concentrations while had inhibitory effect on soil bacteria, actinomyces and fungus at high concentrations. When the concentration of La was low, soil azotobacter was stimulated slightly while soil nitrifier was stimulated strongly and the maximum increase was up to 50%. When the concentration of La was high, both soil azotobacter and nitrifier were inhibited, and the inhibition of La to the nitrifier increased with La concentration. La added at all the levels had stimulative effect on soil inorganic and organic phosphobatteria. Among the 4 physiological groups, soil nitrifier was most sensitive to La, so , it might be reasonable to assume that soil nitrifier was a sensitive indicator for evaluating the biological and environmental effects of rare earths. 展开更多
关键词 LANTHANUM microbial populations physiological groups rare earths red soil
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Effect of Soybean Peptides on in vitro Ruminal Fermentation and Microbial Population 被引量:1
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作者 Wang Li-jun Liu Yan +4 位作者 Liu Shuai Sun Kai-jing Wang Xin-ying Zhang Guang-ning Zhang Yong-gen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第4期40-52,共13页
This study was conducted to investigate the effect of Soybean Peptides(SPs) on ruminal fermentation and microbial diversity in vitro. Four levels of SPs supplements(0, 0.25%, 0.50% and 0.75% dry matter basis) were tes... This study was conducted to investigate the effect of Soybean Peptides(SPs) on ruminal fermentation and microbial diversity in vitro. Four levels of SPs supplements(0, 0.25%, 0.50% and 0.75% dry matter basis) were tested. p H, NH3-N, Neutral Detergent Fiber(NDF), Acid Detergent Fiber(ADF), Dry Matter Digestibility(DMD) and the Total Volatile Fatty Acid(TVFA) were measured at 6, 24, 48 h of in vitro mixed incubation the fluids. Microbial populations were determined at 24 h and Microbial Proteins(MCP) were determined at 24 and 48 h. The gas production after 48 h in vitro incubation presented linear growth(p<0.05) and the highest content was the level of 0.5% SPs(dry matter basis). NH3-N concentration reached the highest concentration with 0.75%(dry matter basis) at 48 h. p H linearly increased(linear, p<0.05) from 6 to 48 h. The digestion of DMD increased with increasing doses of SPs at 24 h. NDF and ADF linearly(p<0.01) decreased by adding SPs. The concentration of TVFA linearly increased(p<0.05) at 6, 24 and 48 h, and reached the highest concentration at the level of 0.75%(dry matter basis). SPs decreased(p<0.05) the molar proportion of acetate and propionate, respectively at 24 and 48 h. Acetat to Propionate ratio(A/P; linear, p<0.05) increased at 48 h, and reached the greatest value at the level of 0.75%(dry matter basis) at 48 h. The populations of rumen Ruminococcus flavefaciens(R. flavefaciens), Ruminococcusalbus(R. albus), Fibrobacter succinogenes(F. succinogenes), Butyrivibrio fibrisolvens(B. fibrisolvens), Streptococcus bovis(S.bovis), Ruminobacter amylophilus(R. amylophilus) and Succinimonas amylolytica(S. amylolytica) were analyzed based on the total rumen bacterial 16 S ribosomal deoxyribonucleic acid(r DNA). The relative abundance of R. flavefaciens and R. albus increased at 24 h, but the relative abundance of F. succinogenes decreased at this time. The incubation of SPs had no effect on the abundance of S. bovis and R. amylophilus. The relative abundance of B. fibrisolvens and S. amylolytica reached the greatest value(p<0.05) at middle doses of SPs inclusion at 24 h. The value of MCPs linearly increased(p<0.05) at 24 and 48 h. These results showed that SPs could improve in vitro fermentation and nutrient digestion of feed substrates, and had the ability to modulate the ruminal fermentation pattern by regulating the composition of functional rumen microbes. Hence, SPs might be a potential feed additive applied in the diets of ruminants. 展开更多
关键词 Soybean Peptide(SP) ruminal fermentation rumal microbial population DIGESTIBILITY
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Effect of probiotics on growth performance, development of small intestinal tract and microbial populations in broilers 被引量:1
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作者 LEI Yan ZHANG Ke-ying +2 位作者 DING Xue-mei BAI Shi-ping JUNG Sik Choi 《Journal of Agricultural Science and Technology》 2009年第4期24-31,39,共9页
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... 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. 展开更多
关键词 probiotic broiler chickens performance intestine development microbial population
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Effect of wastewater COD/N ratio on aerobic nitrifying sludge granulation and microbial population shift 被引量:30
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作者 Lei Wu Chengyao Peng Yongzhen Peng Lingyun Li Shuying Wang Yong Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第2期234-241,共8页
The effect of COD/N ratio on the granulation process and microbial population succession was investigated.Four identical sequencing batch reactors,R1,R2,R3 and R4,were operated with various initial COD/N ratios rangin... The effect of COD/N ratio on the granulation process and microbial population succession was investigated.Four identical sequencing batch reactors,R1,R2,R3 and R4,were operated with various initial COD/N ratios ranging from 0/200 to 800/200(m/m).Ethanol was fed as the source of COD.Aerobic granules were successfully cultivated in R2 and R3,operating with the COD/N ratio of 200/200 and 400/200,respectively.Scanning electron microscope observations indicated that short rod-shaped and spherical bacteria were dominant in R2,while granules produced in R3 were surrounded with a large amount of filamentous bacteria.The average specific nitritation rate in R2 and R3 were 0.019 and 0.008 mg N/(mg MLVSS.hr),respectively.Fluorescence in situ hybridization results demonstrated that nitrifying bacteria population was enriched remarkably in R2.It indicated that nitrification ability and nitrifying bacteria population were enriched remarkably at low COD/N ratio.However,no granules were formed in R1 and R4 which might attribute to either limited or excessive extracellular polymeric substances production.This study contributed to a better understanding of the role of COD/N ratio in nitrifying sludge granulation. 展开更多
关键词 aerobic granules COD/N ratio sequencing batch reactor nitrification performance microbial population shift
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Effects of feeding whole linseed on ruminal fatty acid composition and microbial population in goats 被引量:8
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作者 Kamaleldin Abuelfatah Abu B.Zuki +2 位作者 Yeng M.Goh Awis Q.Sazili Abdelrahim Abubakr 《Animal Nutrition》 SCIE 2016年第4期323-328,共6页
The objective of the present study was to evaluate the effect of feeding different levels of whole linseed,as a source of n-3 polyunsaturated fatty acids(PUFA), on ruminal fatty acid composition and microbial populati... The objective of the present study was to evaluate the effect of feeding different levels of whole linseed,as a source of n-3 polyunsaturated fatty acids(PUFA), on ruminal fatty acid composition and microbial population in the goat. Twenty-four crossbred Boer goats were assigned to 3 dietary treatments: LO(control), L10 and L20 containing 0,10%, or 20% whole linseed, respectively. The ruminal pH and concentration of total volatile fatty acids(VFA) were not affected by dietary treatments. The feeding of L10 and L20 diets produced higher(P < 0.05) molar proportions of acetate and lower(P < 0.05) molar proportions of butyrate and valerate than the LO diet. Molar proportions of myristic acid(C14:0) and palmitic acid(C16:0) were lower(P < 0.05) in the rumen of goats offered L10 and L20 diets than the control diet. However, stearic acid(C18:0), vaccenic acid(C18:1 trans-11), conjugated linoleic acid(CLA,C18:2 trans-10, cis-12) and a-lenolenic acid(C18:3 n-3) were higher(P < 0.05) in the rumen of goats fed L10 and L20 than L0. Both inclusion levels of linseed in the diet(L10 and L20) reduced the ruminal total bacteria, methanogens, and protozoa compared with LO(P < 0.05). The effect of the dietary treatments on cellulolytic bacteria, varied between the individual species. Both inclusion levels of linseed resulted in a significant decrease(P < 0.05) in the population of Fibrobacter succinogenes, and Rumunococus flavefaciens compared with LO, with no significant difference between the groups fed linseed diets. The population of Rumunococus albus was not affected by the different dietary treatments. It was concluded that inclusion of whole linseed in the diet of goats could increase the concentration of PUFA in the rumen, and decrease the population of F. succinogenes, R. flavefaciens, methanogens and protozoa in rumen liquid of goats. 展开更多
关键词 Whole linseed RUMEN microbial population Fatty acid GOAT
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Microbial population dynamics and changes in main nutrients during the acidification process of pig manures 被引量:4
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作者 Dongdong Zhang Xufeng Yuan +4 位作者 Peng Guo Yali Suo Xiaofen Wang Weidong Wang Zongjun Cui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第3期497-505,共9页
This study evaluated the impact of pig manure acidification on anaerobic treatment and composition of the fecal microbial community. According to the different chemical oxygen demand (COD) in the anaerobic treatment... This study evaluated the impact of pig manure acidification on anaerobic treatment and composition of the fecal microbial community. According to the different chemical oxygen demand (COD) in the anaerobic treatment processes, pig manure was diluted 4 times (×4), 16 times (×16), or 64 times (×64) and subjected to acidification. During the acidification process, pH, soluble chemical oxygen demand (SCOD), volatile fatty acids (VFAs), nitrogen (N), phosphorus (P) and potassium (K) were determined along with microbial population dynamics. The pH of the three dilutions first declined, and then slowly increased. The total VFAs of x4 and xl6 dilutions peaked on day 15 and 20, respectively. The content of acetic acid, propanoic acid, butanoic acid and valeric acid of the × 4 dilution were 23.6, 11.4, 8.8 and 0.6 g/L respectively, and that of the xl6 dilution was 5.6, 2.3, 0.9 and 0.2 g/L respectively. Only acetic acid was detected in the ×64 dilution, and its level peaked on day 10. The results showed that the liquid pig manure was more suitable to enter the anaerobic methanogenic hioreactors after two weeks of acidification. During the acidification process, total P concentration increased during the first ten days, then dropped sharply, and rose again to a relatively high final concentration, while total N concentration rose initially and then declined. Based on the analysis of denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library, we concluded that the acidification process reduced the number of pathogenic bacteria species in pig manure. 展开更多
关键词 pig manure ACIDIFICATION microbial population dynamics
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Enzymatic pretreatment mitigates the dissemination of antibiotic resistance genes via regulating microbial populations and gene expressions during food waste fermentation 被引量:1
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作者 Yang Wu Wanying Hu +3 位作者 Haining Huang Xiong Zheng Lei Dong Yinguang Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第8期259-264,共6页
Food waste(FW)has been recognized as essential reservoir for resource recovery via anaerobic fermentation,which could also bring the potential risk of antibiotic resistance genes(ARGs)dissemination.Although the struct... Food waste(FW)has been recognized as essential reservoir for resource recovery via anaerobic fermentation,which could also bring the potential risk of antibiotic resistance genes(ARGs)dissemination.Although the structural deficiency of FW could be stimulated by enzymatic pretreatment to enhance fermentation efficiency,the influences of enzymatic pretreatment on ARGs fate and microbial metabolic pathways involved in ARGs dissemination have rarely been reported.This work proved that enzymatic pretreatment could effectively decrease the total abundance of ARGs(reduced by 13.8%-24.5%)during long-term FW fermentation.It was found that enzymatic pretreatment significantly reduced the ARGs belonging to the efflux pump,which might be ascribed to its ability to increase membrane permeability.Furthermore,enzymatic pretreatment was in favor of reducing microbial diversity and various potential ARGs host(e.g.,Methanosarcina,Clostridium,Prevotella,Parabacteroides).Also,this pretreatment remarkably up-regulated the genetic expressions involved in ABC transporter(e.g.,eryF and mntA)and down-regulated the genetic expressions that participated in DNA replication,two-component systems(e.g.,uphA and cckA),and quorum sensing(e.g.,rpfF and lsrG),thereby decreasing ARGs transmission.This study would expand the insight of the influences of pretreatment method on ARGs fate during FW fermentation,and offer practical guidance on the sustainable management of FW. 展开更多
关键词 Food waste(FW) Antibiotic resistance genes(ARGs) Enzymatic pretreatment microbial populations Metabolic pathways
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Temporal variation of microbial population in a thermophilic biofilter for SO_2 removal 被引量:2
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作者 Jingying Zhang Lin Li Junxin Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第1期4-12,共9页
The performance of a biofilter relies on the activity of microorganisms during the gas contaminant treatment process. In this study, SO2 was treated using a laboratory-scale biofilter packed with polyurethane foam cu... The performance of a biofilter relies on the activity of microorganisms during the gas contaminant treatment process. In this study, SO2 was treated using a laboratory-scale biofilter packed with polyurethane foam cubes(PUFC), on which thermophilic desulfurization bacteria were attached. The thermophilic biofilter effectively reduced SO2 within 10 months of operation time, with a maximum elimination capacity of 48.29 g/m^3/hr.Temporal shifts in the microbial population in the thermophilic biofilter were determined through polymerase chain reaction-denaturing gradient gel electrophoresis and deoxyribonucleic acid(DNA) sequence analysis. The substrate species and environmental conditions in the biofilter influenced the microbial population. Oxygen distribution in the PUFC was analyzed using a microelectrode. When the water-containing rate in PUFC was over 98%, the oxygen distribution presented aerobic–anoxic–aerobic states along the test route on the PUFC. The appearance of sulfate-reducing bacteria was caused by the anaerobic conditions and sulfate formation after 4 months of operation. 展开更多
关键词 Thermophilic biofilter Sulfur dioxide microbial population DGGE analysis O2 distribution
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Heavy metal contamination, physico-chemical and microbial evaluation of water samples collected from chromite mine environment of Sukinda, India 被引量:5
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作者 S. DAS S. C. PATNAIK +3 位作者 H. K. SAHU A. CHAKRABORTY M. SUDARSHAN H. N. THATOI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期484-493,共10页
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... 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. 展开更多
关键词 BIOREMEDIATION hexavalent chromium physico-chemical properties mine water pollution microbial population chromium tolerant bacteria
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Bioactive Characteristics of Soil Microorganisms in Different-aged Orange (Citrus reticulate) Plantations 被引量:1
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作者 刘菊 夏会娟 +1 位作者 王建柱 张文丽 《Agricultural Science & Technology》 CAS 2012年第6期1277-1281,1286,共6页
[Objective] The paper was to study the bioactive characteristics of soil microorganisms in different-aged orange plantations. [Method] Taking 010 cm deep soil in 3 orange plantations with different planting years in s... [Objective] The paper was to study the bioactive characteristics of soil microorganisms in different-aged orange plantations. [Method] Taking 010 cm deep soil in 3 orange plantations with different planting years in suburb of Yichang City as the test object, the variation rule of total organic carbon, total nitrogen, soil pH value, microbial biomass carbon, microbial biomass nitrogen, number of 3 main types of soil microbial flora, basal respiration, microbial entropy and metabolic entropy in differentaged orange plantations was studied. [Result] With the increase of planting years, the soil acidification of different-aged orange plantations was aggravating; total organic carbon and total nitrogen content increased first and then decreased; the total number of soil microorganism showed a downtrend, of which the number of bacteria decreased significantly, the number of actinomycetes had small changes, the number of fungi increased significantly, and the ratio of bacteria and fungi in soil (B/F) showed a decreasing trend. Soil microbial biomass carbon was fluctuated within a small range, whereas soil microbial biomass nitrogen decreased significantly; soil microbial entropy decreased significantly, and metabolic entropy showed an increasing trend. This indicated that the decrease of soil pH value affected the changes of soil microbial flora, microbial activity, microbial biomass carbon and nitrogen and soil major nutrients, and further affected the normal exertion of soil function. [Conclusion] The study explores soil nutrient characteristics and changes of microbial flora in test area, which will provide scientific basis for further study on orchard soil and orchard management. 展开更多
关键词 Planting year Artificial forest microbial population Soil microbial biomass microbial activity
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Degradation of crude oil by indigenous microorganisms supplemented with nutrients 被引量:16
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作者 XIAWen-xiang ZHENGXi-lai +2 位作者 LIJin-cheng SONGZhi-wen SUNHao-fen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第4期659-661,共3页
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... 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. 展开更多
关键词 oil spill biodegradation kinetics N/P ratio microbial population
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Preliminary investigation on the role of microorganisms in the production of phosphine 被引量:10
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作者 LIU Zhipei JIA Shengfen WANG Baojun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期885-890,共6页
The relationships between the phosphine content and various microbial populations,activities of different enzymes were investigated firstly.The results indicated that the phosphine content of samples from various envi... The relationships between the phosphine content and various microbial populations,activities of different enzymes were investigated firstly.The results indicated that the phosphine content of samples from various environments was positively related to total anaerobic microorganisms,organic phosphate compound-dissolving bacteria,denitrifying bacteria,and the activities of alkaline phosphatase and dehydrogenase,with correlation coefficients (R^2) up to 0.93,0.90,0.69,0.79,and 0.82,respectively.Results also sh... 展开更多
关键词 phosphane content microbial populations enzymatic activities sulfate reducing bacteria denitrifying bacteria
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Reduction of Nitrate to Ammonium in Selected Paddy Soils of China *1 被引量:6
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作者 YINSHIXUE SHENQIRONG 《Pedosphere》 SCIE CAS CSCD 1998年第3期221-228,共8页
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 ... 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. 展开更多
关键词 carbon source dissimilatory reduction of nitrate to ammonium microbial population
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Antioxidant compounds and minerals in tomatoes by Trichodermaenriched biofertilizer and their relationship with the soil environments 被引量:4
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作者 Yeakub Khan Manjurul Haque +2 位作者 Abul Hossain Molla Mizanur Rahman Mohammad Zahangeer Alam 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第3期691-703,共13页
The experiment was conducted to evaluate the efficacy of Trichoderma-enriched biofertilizer(BioF/compost)on antioxidants and minerals in ripe tomatoes and soil health improvements in terms of nutrient availability a... The experiment was conducted to evaluate the efficacy of Trichoderma-enriched biofertilizer(BioF/compost)on antioxidants and minerals in ripe tomatoes and soil health improvements in terms of nutrient availability and microbial populations.The study was comprised of six treatments:control(zero input);recommended doses of NPK(135.5,45.6 and 22.9 kg ha^-1,respectively);100%BioF/compost;75%BioF/compost+25%N;50%BioF/compost+50%N;and 25%BioF/compost+75%N.The recommended doses of P and K were used in the last three treatments.It was found that the application of 100%BioF/compost enhanced plant growth,leaf greenness,and produced 12.9%higher yield compared to the recommended doses of NPK and other treatments.Mineral contents(P,K,Ca,Mg,Cu,Fe,Mn and Zn)in tomato roots,shoots and fruits and antioxidant compounds,i.e.,ascorbic acid,β-carotine,and lycopene were increased significantly in fruits fertilized with100%BioF/compost.The high efficiency of Trichoderma compost might be the result of its potential of nutrient solubilization and harboring soil microorganisms.Collectively,BioF/compost increased soil fertility and favored growth of microbes in the rhizosphere which ultimately contributed to higher yield,antioxidant,and mineral concentrations in tomatoes.Thus,Trichoderma-enriched biofertilizer may reduce application of chemical fertilizers and therefore,can be considered as a noble practice in sustainable agriculture. 展开更多
关键词 Trichoderma harzianum T22 MINERALS .antioxidants nutrient availability microbial populations
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Comparison of Soil Biota Between Organic and Conventional Agroecosystems in Oregon, USA 被引量:2
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作者 WUShan-Mei HUDun-Xiao E.R.INGHAM 《Pedosphere》 SCIE CAS CSCD 2005年第3期395-403,共9页
Soil samples at 0-10 cm in depth were collected periodically at paired fields in Corvallis, Oregon, USA to compare differences in soil microbial and faunal populations between organic and conventional agroecosystems. ... Soil samples at 0-10 cm in depth were collected periodically at paired fields in Corvallis, Oregon, USA to compare differences in soil microbial and faunal populations between organic and conventional agroecosystems. Results showed that the organic soil ecosystem had a significantly higher (P < 0.05) average number or biomass of soil bacteria; densities of flagellates, amoebae of protozoa; some nematodes, such as microbivorous and predaceous nematodes and plant-parasitic nematodes; as well as Collembola. Greater numbers of Rhabditida (such as Rhabditis spp.), were present in the organic soil ecosystem while Panagrolaimus spp. were predominant in the conventional soil ecosystem. The omnivores and predators of Acarina in the Mesostigmata (such as Digamasellidae and Laelapid), and Prostigmata (such as Alicorhaiidae and Rhagidiidae), were also more abundant in the organic soil ecosystem. However, fungivorous Prostigmata (such as Terpnacaridae and Nanorchestidae) and Astigmata (such as Acarida) were significantly higher (P < 0.05) in the conventional soil ecosystem, which supported the finding that total fungal biomass was greater in the conventional soil ecosystem. Seansonal variations of the population depended mostly on soil moisture condition and food web relationship. The population declined from May to October for both agroecosystems. However, higher diversities and densities of soil biota survived occurred in the organic soil ecosystem in the dry season. 展开更多
关键词 MICROARTHROPODS nematodes organic and conventional agroecosystems soil microbial population
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