30 research outputs found

    DEGRADATION OF METHAMIDOPHOS BY MANGROVE SOIL MICROBES

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    连续 3年 (a)的试验结果表明 :红树林土壤微生物对农药甲胺磷有较强的降解能力 ,其降解率是同潮带无红树林土壤微生物的 2 - 3倍 ;红树林土壤中存在着降解甲胺磷的优势细菌类群 ,从中筛选得一株高效降解菌 ,其降解率可达 70 %以上 (12d后 ) ;混合菌的降解能力优于单株菌 ;优势降解菌在一定浓度的甲胺磷、适宜的通气、温度和光照等条件下 ,可发挥更佳的降解作用 ;在降解过程中 ,降解优势细菌类群有着明显菌群变化 ,那种一直占优势的菌株可选育为“工程菌” ;红树林土壤微生物具有多功能的环境效应和经济效益 .图 5表 5参 4Degradation of methamidophos by mangrove soil microbes was studied for successive three years. The results indicated: ① Mangrove soil microbes had a better ability of methamidophos degradation, and their degradation rate is 2~3 times higher than that of non-mangrove soil microbes. ② There were some dominant populations in mangrove soil, from which a high efficient strain was isolated; the degradation rate of the strain might be as high as 70% (after 12 days), however, the rate of mixed bacteria was higher than that of single strain. ③ The dominant bacteria had stronger degradation ability under a certain concentration of methamidophos, adaptive ventilation, temperature, and light . ④ The obvious changes of strains in dominant populations could be observed during the course of degradation, of which the "engineering strain” can be sifted out of the dominant strains from beginning to end. ⑤ Multiple environmental effects and economic benefits could be further verified in mangrove soil microbes as well. Fig 5, Tab 5, Ref

    Abiogenous azotobacter on the body of Caloglossa leprieurii growing in Kandelia candel mangrove forest in Jiulongjiang estuary of Fujian Province

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    初步研究了福建九龙江口秋茄(Kandelia candel)红树林红藻鹧鸪菜(Caloglossa leprieurii)藻体异养自生固氮菌数量的季节变化和微生物区系。结果表明:鹧鸪菜上异养自生固氮细菌数量以春季最多(1.033×104cfu.g-1),冬季最少(0.567×104cfu.g-1),固氮菌的季节变化模式表现为春季>秋季>夏季>冬季;鹧鸪菜藻体氮含量也以春季最高(22.08g.kg-1),冬季最低(16.63g.kg-1),二者差异显著(Pautumn>summer>winter.The nitrogen concentration of C.leprieurii also had the same seasonal pattern,being the highest in spring(22.08 g·kg-1)and the lowest in winter(16.63 g·kg-1),which was closely related to the growth and matter accumulation of the seaweed.There was probably a kind of special cooperative relation between the azotobacter and the seaweed,which was influenced simultaneously by the environmental factors such as temperature,water,and others.The preliminary identification of isolated nine strains azotobacter showed that they were belonged to Azotobacter or Beijerinckia.国家自然科学基金资助项目(30270272

    Microbial Study of Mangrove Soil at Dongzhai Harbor in Hainan.

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    Three groups of microbial amount of mangrove soil at Dongzhai harbor in Hainan were studied.The results show as follows:①Mean amount of soil bacteria in Kandelia candel forest and Bruguiera sexangula forest is 4 87×10 7 and 7 55×10 7〔ind·(g.dry soil) -1 〕 respectively,which is higher than that of controlled mudflat without mangrove forest〔1 22×10 7ind·(g.dry soil) -1 〕;②The amount of bacteria at layer of 10-20cm is the most in three layers of 0-10、10-20 and 20-30cm;③Mean amount of soil bacteria in Bruguiera sexangula forest is higher than that in Kandelia candel forest;④The amount of bacteria is related to the amount and distribution of plant residue and litter;⑤Filamentous fungi and actinomyces are not found out by normal isolation methods,which is perhaps related to least amount and special habitat of local mangrove soil.国家教委高校湿地研究中心专项经费资助项

    Biochemical characters of forest soils at Wuyishan Mountain.

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    研究了武夷山自然保护区森林土壤生化特性.结果表明,不同生境土壤呼吸作用、纤维分解作用和硝化作用等3项生化强度有明显差异,先峰岭(常绿阔叶林)>大竹岚(毛竹林).同一生境中的不同小生境3项生化强度的差异也很显著,尤其是呼吸作用强度,落叶层>腐殖层>土壤层;纤维分解作用强度,腐殖层>落叶层>土壤层;硝化作用强度,土壤层>落叶层>腐殖层.无论那一种生境3项生化强度之间,呼吸作用强度与纤维分解作用强度有一定相关性,而硝化作用强度与前两项未显示相关.不同生境土壤蔗糖酶、纤维素酶和蛋白酶等活性显著不同,大竹岚>先峰岭.同一生境中的不同小生境3种酶活性随土壤剖面深度而降低;蔗糖酶是各生境中活性最大酶类,变化较剧;纤维素酶和蛋白酶则活性较小,变化较缓和.Studies on the biochemical characters of forest soils in Wuyishan Mt.Natural Reserve show that the rates of soil respiration, cellular decomposition and nitrification differed obviously with habitats.Soils under broad leaved evergreen forest ( Castanopsis eyrei ) at Xianfengling had higher rates than those under moso bamboo forest ( Phyllostachys heterocyca var. pubescens ) at Dazhulan.The three rates at each habitat also significantly differed with microhabitats: for respiration rate, litter layer>humus layer>soil layer; and for nitrification rate, soil layer>litter layer>humus layer; for cellular decomposition rate, humus layer>litter layer>soil layer.Among the three rates at each hibitat, there existed a definite relationship between respiration rate and cellular decomposition rate, while the nitrification rate was independent of the other two.The activities of sucrase, celluase and proteinase varied with different habitats, which were higher at Dazhulan than at Xianfengling, and decreased with increasing soil depth.Among the three enzymes, sucrase had the highest activity at all microhabitats, and the variation of its activity was greater.福建省自然科学基金;武夷山自然保护区管理局资助项

    Succession of phytoplankton community in exalted shrimp ponds during culture process

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    通过对湛江东海岛北寮村和庵里村各2个高位虾池养殖过程的浮游植物演替和主要理化因子进行调查,研究浮游植物群落的演替过程对高位虾池的健康养殖的影响。结果表明:4池共检出浮游植物7门76属140种;对虾生长正常的北寮高位虾池演替优势种主要有螺旋环沟藻、椭圆扁胞藻、海链藻、湖泊束球藻密胞变种、裸甲藻、卵囊藻、微囊藻、锥形斯克里普藻、色球藻和尖尾蓝隐藻等,而对虾发病的庵里高位虾池演替优势种主要有铜绿微囊藻、柔弱布纹藻、咖啡形双眉藻、小席藻、卷曲鱼腥藻、水生集胞藻、衣藻、尖尾蓝隐藻和螺旋环沟藻等,北寮正常虾池浮游植物种类(包括优势种)较对虾发病的庵里虾池多而复杂;对虾生长正常池优势种的演替快而门类交替,而对虾发病池呈现硅藻到蓝藻优势的演替;对虾生长正常池浮游植物密度随养殖过程延伸呈上升态势,而对虾发病池浮游植物密度初期增加病害后下降;养殖过程浮游植物密度与主要理化因子的相关关系不显著;对虾生长正常的北寮高位池多样性指数与均匀度高于对虾发病的庵里高位池,而优势度却较低。水体理化因子变化平缓,浮游植物有较高的多样性指数和均匀度、较低的优势度对于稳定虾池养殖水环境有重要作用。An investigation was made on the succession of phytoplankton community and the main physical and chemical factors of water body in exalted shrimp ponds in Beiliao and Anli villages of Donghai Island,Zhanjiang during culture process,with the influence of the succession on the culture process analyzed.A total of 140 species of phytoplankton belonging to 76 genera and 7 phyla were identified.The dominant species in the two ponds with normal shrimp growth in Beiliao village were Gyrodinium spirale,Platymonas elliptica,Thalassiosira sp.2,Gomphosphaeria lacustris var.compacta,Gymnodinium sp.1,Oocystis sp.,Microcystis sp.,Scrippsiella trochoidea,Chroococcus sp.,and Chroomonas acuta,while those in the two ponds with shrimp disease occurrence in the process of culture in Anli village were Microcystis aeruginosa,Gyrosigma tenuissimum,Amphora coffeaeformis,Phormidium tenue,Anabaena circinlis,Synechocydtis aquetilis,Chlamydomonas sp.2,Chroomonas acuta,and Gyrodinium spirale.The phytoplankton species,including dominant ones,were more abundant and complex in normal ponds than in disease-affected ponds.In normal ponds,the dominant species succeeded rapidly and alternated in phyla,while in disease-affected ponds,only Bacillariophyta species were replaced by Cyanophyta species during the succession.The phytoplankton cell density increased during the culture process in normal ponds,but decreased after a temporary increase at early culture stage in disease-affected ponds.No significant relationships were observed between the phytoplankton cell density and the main physical and chemical factors in the ponds during culture process.The diversity and evenness of phytoplankton species were higher in the normal ponds in Beiliao than in the disease-affected ponds in Anli,while the dominance degree of species was in reverse.The mild variability of water body's physical and chemical factors as well as the high diversity and evenness but low dominance degree of phytoplankton species played important roles in keeping aquatic environment steady and healthy during the culture process in exalted shrimp pond.广东省自主创新重大科技资助项目(2007A032600004

    Determination of 19 Organophosphorous Pesticides Residues in Milk Drink and Milk Powder by Gas Chromatography-Negative Chemical Ionization-Mass Spectrometry

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    将气相色谱-负离子化学源质谱法(GC-NCIMS)应用于牛奶饮品和奶粉中19种有机磷农药残留的同时分析。牛奶饮品和奶粉经乙腈提取剂超声提取、Florisil硅藻土和中性氧化铝双净化剂同时净化及正己烷-乙酸乙酯(体积比1∶1)混合洗脱剂洗脱后,以三苯基磷酸酯为内标物,采用GC-NCI MS的选择离子监测方式(SIM)定性与定量分析。当牛奶饮品和奶粉的加标浓度水平为20、100、500μg/kg时,平均加标回收率为64.5%~129%,相对标准偏差为2%~20%;除喹硫磷的方法检出限(MDL)为2.4μg/kg外,其余18种有机磷农药的MDL均小于1.0μg/kg;线性范围为10~500μg/kg,相关系数均大于0.9988,此分析方法成功地应用于牛奶饮品和奶粉中多种痕量有机磷农药残留的分析。A rapid method was developed for the determination of 19 organophosphorous pesticides residues in commercial milk drink and milk powder.Under optimized conditions,the pesticides were extracted from milk drink or milk powder with acetonitrile in an ultrasonic bath and cleaned up on a Florisil and neutral alumina column,and were determined by gas chromatography with negative chemical ionization mass spectrometric detection in the selected ion monitoring mode with triphenyl phosphate as internal standard.The recoveries for all the pesticides studied ranged from 64.5% to 129% with a relative standard deviation range of 2%-20%.The detection limit of the method was less than 1.0 μg/kg for most of the pesticides except for the quinolphos.The linear ranges of the calibration curves ranged from 10 μg/kg to 500 μg/kg with correlation coefficients of 0.998 8.The proposed method was successfully applied to the analysis of these compounds in milk drink and milk powder

    Determination of Five Polybrominated Diphenyl Ether Residues in Deep-Sea Fish Oil Using Gas Chromatography-Negative Chemical Ionization/Mass Spectrometry

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    建立了气相色谱-负离子化学电离质谱法(GC-NCI/MS)同时分析深海鱼油食品中5种多溴联苯醚残留的分析方法。深海鱼油食品用正己烷超声提取、中性与酸性硅胶色谱柱净化和正己烷洗脱后,以PCB103为内标物,采用GC-NCI/MS的选择离子监测方式(SIM)分析;同时探讨了5种多溴联苯醚的NCI/MS特征离子的断裂机理。当空白深海鱼油食品的加标浓度为20.0和100.0μg/kg时,加标回收率为88.6%-111.3%,相对标准偏差为3.8%-13.5%,方法的检测限为0.77-1.34μg/kg,线性范围为1.0-500.0μg/kg,相关系数均大于0.999 2。此方法已成功地应用于深海鱼油食品中5种痕量多溴联苯醚残留的同时分析。Polybrominated diphenyl ethers(PBDEs) are a kind of brominated flame retardants(BFRs),which refer to compounds used in some plastics to impede or even suppress the combustion process.As the emission or disposal of plastics,PBDE residues have been found in both environment and biota.In this work,an analytical method was developed for the simultaneous determination of 5 PBDE residues in deep-sea fish oil.PBDEs were extracted from deep-sea fish oil with n-hexane,cleaned up on a silical gel column,and determined by using gas chromatography-negative chemical ionization/mass spectrometry(GC-NCI/MS) in the selected ion-monitoring(SIM) mode,with PCB103 as the internal standard.Meanwhile,the characteristic ion and fragmentation mechanism of some PBDEs in NCI/MS were evaluated.Recovery studies were performed at 20.0 and 100.0 μg/kg fortification levels for each PBDE,and the recoveries ranged from 88.6% to 111.3% with relative standard deviations between 3.8% and 13.5% for different PBDEs.The limits of detection(LOD) were from 0.77 to 1.34 μg/kg for different PBDEs.The developed method was linear over the range assayed,1.0-500.0 μg/kg,with correlation coefficients larger than 0.999 2.The developed method has also been successfully applied to the determination of PBDEs in several deep-sea fish oil samples and the three most abundant PBDEs(PBDE-47,PBDE-99 and PBDE-100) were found

    Relation between soil salinity in intertidal zone and electric conductivity

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    以5∶1的水土质量比浸提潮间带土壤,质量法测定的土壤盐度(质量分数),与电导法测定的稀释了5倍的土壤浸提液(5∶1水土质量比)的电导率值之间有极显著的相关性。质量法实测的土壤盐度与电导率计算的土壤盐度之间的相对误差多在5%以下。因此,用电导法测定潮间带土壤盐度不失为一种简便、快速的方法,尤其是样品数较多时更可节约时间。 【英文摘要】 There was significantly correlation between soil salinity in intertidal zone obtained by mass method (the ratio of mass of water to soil is 5∶1) and electric conductivity of extracting solution diluted five times by electric conductivity method The relative errors were almost below 5% between soil salinity measured by the mass method and the ones calculated by electric conductivity. So, electric conductivity method is a simple and rapid method for measurement of soil salinity in intertidal zone after defini...国家自然科学基金项目(30270272

    Effect of salinity on microbial densities of soil in the dilution plate technique applied in mangrove areas

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    作者简介:张瑜斌(1970~) ,男,湖南郴州人,博士,副教授,主要从事海洋微生物学与海洋生态学研究. E2mail: zhangyb@gdou. edu. cn 通讯作者Corresponding author. E2mail: linpeng@jingxian. xmu. edu. cn[中文文摘]在使用稀释平板法分离潮间带红树林及其对照光滩土壤微生物以及计数时,多数情况下使用陈海水制作培养基和稀释水,很少考虑培养基和稀释水的盐度对最终计数结果的影响。使用稀释平板法研究了盐度对福建九龙江口红树林区与深圳福田红树林保护区土壤微生物平板计数的影响,结果表明培养基与稀释水盐度对微生物数量有明显的影响。统计分析显示细菌的海水稀释效果优于淡水,而放线菌与真菌则刚好相反(P<0.05,一个例外)。海水不适合配制红树林区土壤微生物平板计数的培养基,从0~35,高盐度的平板培养基会降低微生物的数量,尤其是放线菌的数量,尽管培养基的盐度对真菌影响无规律,但细菌数量在低盐度时比在高盐度和不加氯化钠时要多。根据盐度效应,提出了稀释平板技术应用于潮间带的红树林及其相应光滩时的优化方法,认为细菌应该用海水作无菌稀释水,而放线菌和真菌则应用淡水作稀释水;包括光滩在内的红树林区土壤微生物分离与计数的培养基宜控制较低盐度范围。[英文文摘]When the soilmicrobial densities are determined in mangroves and correspondingmudflat at the same tidal level by the dilution p late method, the agarmedia and dilution water are generallymade up of aged seawater in most cases, and effects of salinity in agar media and dilution water on the enumeration of microbes is seldom taken into consideration. The effects of salinity on soil microbial counting from the samples in mangrove areas in Jiulongjiang Estuary of Fujian, and Futian Mangrove Nature Reserve of Shenzhen, China, were tested by dilution p late technique. The results showed that the soil microbial densities in mangroves and mudflat were significantly influenced by the salinity of dilution water and agarmedia. For the bacteria, the seawater served as sterilized dilution water was significantly ( P < 0. 05) more benefic to the enumeration on the p lates than the freshwater, but in reverse for the actinomycetes and fungi. The increasing salinity of media within 35 significantly decreased microbial colonies on the p lates, especially for the actinomycetes, in sp ite of the fact that the effect of salinity ofmedia on fungal numberswas not indefinite. The bacterial colonieswere more abundant on the agar p lates with low salinity than with high salinity or without any NaCl. It was p roposed that some methodological imp rovements were needed when the dilution p late technique was app lied to microbial counting in the samp les of mangrove forest and mudflat at the same tidal level in inter2tidal zone. The sterilized dilution water should be p repared with seawater for the bacteria, but with freshwater or low saline water for the actinomycetes and fungi. The salinity of agarmedia should be low for the microbial isolation and enumeration of soil samples from the mangrove areas including mudflats.国家自然科学基金资助项目(30270272

    Some Ecological Studies on Soil Microorganisms and Heterotrophic Nitrogen-fixing Bacteria on Caloglossa Body in Mangroves of Jiulongjiang Estuary, Fujian of China

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    红树林(mangroves)是自然分布于热带、亚热带海岸的潮间带的木本植物群落。微生物是生态系统的组成成分、最主要的分解者,推动着生态系统的物质循环与能量流动。本文通过经典的微生物学和生态学的实验手段,利用生物统计分析方法,研究了亚热带的九龙江口红树林区0-60cm土壤层的细菌、放线菌与丝状真菌3大类异养微生物数量的垂直分布、季节动态和区系;土壤环境因子的动态及其与土壤微生物数量动态的关系;红树林区红藻鹧鸪菜(Caloglossa)上异养固氮菌的季节动态和区系,异养固氮菌的季节动态与藻体营养元素的关系;优化了微生物学中经典的分离方法在红树林区的应用;测定了红树林土壤微生物的抗菌活性。 1. ...Mangrove forests are woody plant communities in the intertidal regimes of tropical and subtropical coasts. Microorganisms are compositions and main decomposers of ecosystem, which promote material cycle and energy flow in ecosystem. In this thesis, it was detailed studied with some classical microbiological and ecological experimental means’ and biological statistical methods that vertical distrib...学位:理学博士院系专业:生命科学学院生物学系_植物学学号:B19992600
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