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1.
库布齐沙地生物土壤结皮中解磷菌的分离鉴定及解磷能力   总被引:1,自引:0,他引:1  
解磷菌对生物土壤结皮(Biological soil crusts,BSCs)中不同形态磷之间的转化起重要的生物驱动作用.以无机磷和有机磷培养基分离筛选库布齐沙地BSCs中的解磷菌,基于16S r RNA基因进行分类鉴定;采用钼锑钪比色法测定菌株解无机磷能力;采用钒钼比色法测定其解植酸磷能力,以植酸酶活性表示.结果共分离得到33株可在无机磷(磷酸钙)培养基上生长迅速的细菌,以Bacillus属和Sphingomonas属为主;其中18株菌可以使PVK培养基变色,解无机磷能力较强,达0.422-3.531 mg/m L;这18株菌中有15株可在植酸钙培养基上生长,其植酸酶活力为2.45-20.84 IU/m L,主要为Sphingomonas属.本研究揭示了库布齐沙地BSCs中可培养解磷菌的类群组成及其解磷能力,结果可为认识和利用荒漠解磷菌提供理论依据和实践基础.  相似文献   

2.
为掌握不同植被恢复措施下鄱阳湖沙地土壤细菌群落变化特征,以湿地松、香根草、单叶蔓荆、狗牙根等植物恢复措施的沙地土壤为研究对象,采用高通量测序技术,分析植物恢复前后细菌群落变化.结果显示,相较对照组,土壤细菌多样性均有提升,在门水平上,绿弯菌门丰度大幅降低,而变形菌门、放线菌门和厚壁菌门丰度增加.在属水平上,副伯克霍尔德氏菌属、慢生根瘤菌属、芽孢杆菌属、分枝杆菌属等丰度提升,而假单胞菌属丰度大幅下降.植被恢复后,不同植被固氮功能细菌丰度提升,而香根草、狗牙根土壤磷细菌丰度下降,湿地松土壤固氮、解磷功能优势细菌提升幅度为76.11%、51.12%,单叶蔓荆为65.04%、23.17%.土壤容重、有机质、全磷、有效氮是影响功能细菌变化的重要因素,其中有效氮与芽孢杆菌属、分枝杆菌属呈显著水平以上相关性.本研究表明鄱阳湖沙地植被恢复措施提升了固氮细菌的丰富度,但不同植被土壤解磷细菌群落变化差异大;研究结果可为沙地治理提供科学依据.(图6表3参34)  相似文献   

3.
缓释肥料对烤烟旺长期解磷细菌的影响   总被引:1,自引:0,他引:1  
研究了缓释肥料对烤烟旺长期解磷细菌的数量以及磷细菌的溶磷能力的影响.结果表明,施用缓释肥料提高土壤中解磷细菌的数量和磷细菌的溶磷能力.施用缓释肥料和普通肥料的土壤中磷细菌总量为分别为7.6×10^6个/g干土和2.3×10^5个/g干土,且磷细菌的总量都高于不施肥的处理.图2,表4,参11.  相似文献   

4.
应用高浓度甲胺磷培养基,对农药厂排污口土壤微生物进行分离,鉴定出21株细菌,分属13个细菌属.对甲胺磷抗性细菌脂肪酸的分析,共测定到38个脂肪酸生物标记(PLFA),这些生物标记分为4种类型,即1)高频次分布的生物标记,普遍存在于细菌类群,属于细菌总体类群(Bacteriaingeneral)的生物标记;2)中频次分布的生物标记,在细菌种出现概率中等,可以用于代表细菌属类群(Bacteriumgenus)识别生物标记;3)低频次分布的生物标记,在细菌中的分布概率较小,可以用于指示特定细菌种间差异的生物标记;4)微频次分布的生物标记,这种生物标记仅在一种细菌种类出现,是细菌种特征生物标记.利用脂肪酸生物标记分析同属细菌不同种的差异,可将假单胞杆菌属分为2类,第1类包括了铜绿假单胞菌、荧光假单胞菌、丁香假单胞菌,其特征为17:0CYCLO生物标记含量小于3.60%;第2类包含了伞菌假单胞菌、威隆假单胞菌、恶臭假单胞菌、温哥华假单胞菌,其特征为17:0CYCLO生物标记含量大于5.99%.利用脂肪酸生物标记的差异对甲胺磷抗性细菌种的聚类分析,能有效地将细菌类群分为3类,微生物群落中存在着稳定的生物标记和受环境影响的生物标记,论文提供了一种脂肪酸生物标记的分析方法,结合细菌的生物学特性研究,可以解释微生物在环境中的变化,对于土壤微生物群落的研究具有重要意义.  相似文献   

5.
利用气体循环培养体系从陕西乾县HUP-豆科植物紫花苜蓿(Medicago sativa)根际土壤中分离获得37株细菌.菌株氧化氢能力测定结果表明,8株菌氧化氢和自养生长能力较强,初步确定为氢氧化细菌类群;根据其形态特征、培养特征和生理生化特性,鉴定为7个不同属:假单胞菌属(Pseudomonas)、邻单胞菌属(Plesiomonas)、脂肪杆菌属(Pimelobacter)、黄色杆菌属(Xanthobacter)、勒米诺氏菌属(Leminorella)、地杆菌属(Terrabacter)和稀有杆菌属(Rarobacter);其中氧化氢能力最强的优势菌株WMQ-7 16S rDNA序列(GenBank登录号为EU807744)长度为1 451bp,GC含量为53.8%,其核苷酸序列与假单胞菌属同源性高于99%,在系统发育树上位于同一分支,将WMQ-7菌株鉴定为假单胞菌属(Pseudomonas).图2表5参16  相似文献   

6.
石灰性土壤中高效解磷细菌菌株的分离、筛选及组合   总被引:13,自引:0,他引:13  
对石灰性土壤样品进行了解磷细菌的分离和筛选,得到具有明显溶磷圈的解磷细菌71株.分析了菌株分泌磷酸酶、释放速效磷及pH降低等综合因素和特征,研究了菌株生长动态.最后筛选出解磷能力较强且无拮抗反应的6株解磷细菌,并将其组合成为解磷细菌菌群.图8表2参17  相似文献   

7.
为了提高城市垃圾堆肥的速效磷含量,对供试的7种垃圾堆肥的解磷强度及解磷微生物进行了分析,并以分离富集的解磷微生物制成解磷菌剂进行了青菜盆栽及大田小区对比试验。结果表明:供试垃圾的解磷强度一般为11700~16100mg/kg;每g垃圾堆肥含3.5~8.6亿个解磷微生物。出现的解磷能力强的微生物有芽孢杆菌属(Bacillusspp.)、假单胞菌属(Pseudomonasspp.)、节杆菌属(Arthrobacterspp.)、黄杆菌属(Flavobacteriumspp.)、产碱菌属(Alcaligenesspp.)和赛氏杆菌属(Serratiaspp.)等。它们可分别使昆阳磷矿粉和/或摩洛哥磷矿粉释放28400~46600mg/kg和29100~36900mg/kg可溶性磷,利用解磷接种物可使垃圾堆肥提高23~25mg/kg速效磷,在往堆肥中添加植物物质和磷矿粉的情况下效果更好。将拌有解磷菌剂的垃圾堆肥在红壤荒地上施用,对青菜有良好的增产效果。  相似文献   

8.
烟区烟草根际与非根际土壤微生物的生态因子作用分析   总被引:5,自引:0,他引:5  
烟草根际和非根际土壤的理化性质、微生物区系和土壤酶之间的相互关系尚缺乏系统研究。对南阳烟区6种土壤包括黄褐土和黄棕壤等共13个取样点的烟草根际和非根际土壤的分析表明,根际与非根际微生物之间没有对应相关关系。根际土壤真菌数与解钾菌数、硝化细菌数显著正相关;非根际土壤荧光假单胞菌数与细菌芽孢数极显著正相关,氨化细菌数与放线菌数显著负相关。与土壤容重和空隙度显著相关的仅有根际真菌数(正相关)。与土壤全氮呈显著正相关的分别有根际荧光假单胞菌、纤维素分解菌(正相关)以及根际解磷菌和非根际真菌(负相关)。土壤全C与根际细菌总数显著负相关。土壤pH与非根际纤维素分解菌显著正相关。速效P与非根际放线菌数呈显著正相关。根际土壤蛋白酶活性与根际细菌总数极显著负相关。非根际土壤蛋白酶活性则分别与非根际放线菌和解钾菌显著正相关。根际土壤脲酶活性分别与根际真菌、解磷菌显著正相关,非根际脲酶活性则与非根际纤维分解菌显著正相关。非根际土壤过氧化氢酶活性与非根际细菌总数显著正相关。  相似文献   

9.
广州城郊菜地土壤磷素特征及流失风险分析   总被引:5,自引:1,他引:5  
通过化学分析和土壤淋洗试验对广州城郊菜地土壤磷素特征和流失风险进行了研究和分析。结果表明.广州城郊菜地土壤全磷含量极高;与自然土壤相比较,菜园土壤无机磷比例增大、有机磷比例降低;无机磷中的AI-P、Fe-P比例增加.O-P比例降低,Ca-P比例基本一致;土壤Olsen P、Bray-1 P、Mehlich-1 P、0.01mol/L CaCl_2和H_2O提取的磷含量相当高;土壤淋洗液中溶解态磷和总磷持续保持很高的浓度,土壤磷供应强度大。菜园土壤中磷进入水体引起水体磷浓度增加,导致水体富营养化风险大;土壤磷的测定值可作为土壤磷流失风险和对水环境影响程度的评估依据。菜地应作为农业非点源磷污染的优先控制区、应通过严格控制磷肥的投入和合理施肥等控制磷的流失。  相似文献   

10.
水源水生物预处理反应器微生物学特征   总被引:5,自引:0,他引:5  
处理微污染水源水的生物陶粒反应器中,细菌的数量分布具有一定的区域化特征,上层生物陶粒的细菌数量较中、下层生物陶粒的细菌数量分别高1~2个数量级。从生物陶粒反应器中分离出72株细菌,其中最多的是假单胞菌属,占44.6%,其次为克雷伯氏菌属细菌,占2l.6%。另外还分离到芽孢杆菌属、不动细菌属、黄单胞菌属和邻单胞菌金的细菌。除芽孢杆菌属外,其它各属细菌生反应器中的分布特征是上层多,下层少。  相似文献   

11.
不同生存环境和磷酸盐对4株溶磷菌溶磷能力的影响   总被引:4,自引:0,他引:4  
利用液体培养法研究了不同NaCl浓度、碳源、氮源、溶解氧及磷酸盐对分离自小麦(Triticum aestivum)、苜蓿(Medicago sativa)根际的4株优良溶磷细菌(Lx81、Jm92、Dm84、Lx191)溶磷能力的影响.结果表明:(1)4株溶磷菌均为高耐盐菌株,其中Jm92和Din84维持较高溶磷量的NaCl浓度最高阈值分别为4%和8%,Lx81、Lx191在NaCl浓度超过5%时溶磷活性受到抑制.(2)Lx81的最佳碳源是葡萄糖,其次为蔗糖;另外3株菌在葡萄糖和蔗糖为碳源时,均有较高的溶磷能力;4株菌都几乎不能利用淀粉.(3)Lx81和Jm92在以(NH_4)_2SO_4和NH_4 NO_3为氮源时溶磷活性均较高,(NH_4)_2SO_4 是Lx191的最佳氮源,而NH~+-N存在会导致Dm84溶磷活性降低.(4)供试4株菌均不是专性厌氧菌,但不同菌株对氧的需求量不同.(5)4株溶磷菌对Ca_3-P和Ca_8-P有较大的溶解效率,但它们几乎都不能溶解Ca_(10)-P.图3表4参14  相似文献   

12.
The occurrence and distribution of a special group of bacteria, capable of dissolving insoluble phosphates, were studied in marine environments, especially in sediments. The phosphatase activity was also investigated. Clayey sediments contained more phosphate solubilizing bacteria and phosphatase than sandy sediments. There was a positive correlation between the total phosphate content and the phosphatase activity. The phosphatase activity was recorded in all samples, irrespective of salinity variations. The role of various factors of the sediments in maintaining the phosphate availability in the overlying water is discussed.Contribution No. 102, Marine Biological Station, Annamalai University, Porto Novo, Tamil Nadu, South India.  相似文献   

13.
研究了不同施肥措施对棉田土壤磷细菌的数量、分布、动态变化及磷转化强度的影响.结果表明,有机肥合理配施N、P、K肥能有效的促进磷细菌的生长发育,磷细菌数量及活性增加,从而增强磷的有效性,改善土壤的供磷性能,有利于棉花生长.  相似文献   

14.
A survey was done recently in Jiaxing city of Zhejiang Province in the Yangtze River Delta to compare the differences of soil microbiological properties among paddy soils with different land use including continuous open-field vegetable cultivation (OFVC), plastic-greenhouse vegetable cultivation (PGVC) and traditional rice–wheat rotation (RWR). The soil types included are percolating, permeable and waterlogged paddy soils. The results indicate that the microbial flora was markedly changed as the land use changed for all the three soil types. In continuous vegetable cultivation soils, especially in PGVC soils, the bacteria amounts decreased dramatically, but the fungal and actinomyce amounts increased as compared with RWR soils. The dehydrogenase activities decreased significantly in vegetable soils, especially in PGVC soils as compared with RWR soils. The microbial biomass C and the total phospholipid contents (TPL) in vegetable cultivation soil greatly decreased as compared with RWR soils. Biolog analysis indicated that the kinds of carbon sources that could be metabolized by native microbes in PGVC soils greatly decreased as compared with OFVC soils and RWR soils, revealing that microbial diversity had decreased since land use change. The activities of some soil enzymes including urease, invertase and phosphase were all lower in OFVC soils than those in RWR soils, and those in PGVC soils were the lowest. The degradation of microbiological activities in continuous vegetable cultivation soils, especially in PGVC soils, as compared with RWR soils might have been caused by soil acidification and accumulation of salts due to overuse of both organic and inorganic fertilizers in vegetable cultivation.  相似文献   

15.
A survey was done recently in Jiaxing city of Zhejiang Province in the Yangtze River Delta to compare the differences of soil microbiological properties among paddy soils with different land use including continuous open-field vegetable cultivation (OFVC), plastic-greenhouse vegetable cultivation (PGVC) and traditional rice-wheat rotation (RWR). The soil types included are percolating, permeable and waterlogged paddy soils. The results indicate that the microbial flora was markedly changed as the land use changed for all the three soil types. In continuous vegetable cultivation soils, especially in PGVC soils, the bacteria amounts decreased dramatically, but the fungal and actinomyce amounts increased as compared with RWR soils. The dehydrogenase activities decreased significantly in vegetable soils, especially in PGVC soils as compared with RWR soils. The microbial biomass C and the total phospholipid contents (TPL) in vegetable cultivation soil greatly decreased as compared with RWR soils. Biolog analysis indicated that the kinds of carbon sources that could be metabolized by native microbes in PGVC soils greatly decreased as compared with OFVC soils and RWR soils, revealing that microbial diversity had decreased since land use change. The activities of some soil enzymes including urease, invertase and phosphase were all lower in OFVC soils than those in RWR soils, and those in PGVC soils were the lowest. The degradation of microbiological activities in continuous vegetable cultivation soils, especially in PGVC soils, as compared with RWR soils might have been caused by soil acidification and accumulation of salts due to overuse of both organic and inorganic fertilizers in vegetable cultivation.  相似文献   

16.
用动态淋洗试验,研究了不同pH的模拟酸雨对红壤中铝形态和性质的影响.结果表明,酸雨淋洗引起红壤中盐基离子的淋失和土壤铝的溶出.随着酸雨溶液pH的降低,盐基淋矢量和铝溶出量增加.酸雨淋洗影响土壤铝形态的转化,使红壤中交换态铝上升,吸附态羟基铝有所下降.这说明在酸雨长期作用下,羟基铝溶解,并转化为交换态铝和引起铝的溶出,使铝进入环境,危害生态系统.  相似文献   

17.
Phosphates for Pb immobilization in soils: a review   总被引:9,自引:0,他引:9  
In its soluble ionic forms, lead (Pb) is a toxic element occurring in waters and soils mainly as the result of human activities. The bioavailability of lead ions can be decreased by complexation with various materials in order to decrease their toxicity. Pb chemical immobilization using phosphate addition is a widely accepted technique to immobilize Pb from aqueous solution and contaminated soils. The application of different P amendments cause Pb in soils to shift from forms with high availability to the most strongly bound Pb fractions. The increase of Pb in the residual or insoluble fraction results from formation of pyromorphite Pb5(PO4)3X where X = F, Cl, Br, OH, the most stable environmental Pb compounds under a wide range of pH and Eh natural conditions. Accidental pyromorphite ingestion does not yield bioavailable lead, because pyromorphite is insoluble in the intestinal tract. Numerous natural and synthetic phosphates materials have been used to immobilize Pb: apatite and hydroxyapatite, biological apatite, rock phosphate, soluble phosphate fertilizers such as monoammonium phosphate, diammonium phosphate, phosphoric acid, biosolids rich in P, phosphatic clay and mixtures. The identification of pyromorphite in phosphate amended soils has been carried out by different non destructive techniques such as X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray absorption fine structure, transmission electron microscopy and electron microprobe analysis. The effectiveness of in situ Pb immobilization has also been evaluated by selective sequential extraction, by the toxicity leaching procedure and by a physiologically based extraction procedure simulating metal ingestion and gastrointestinal bioavailability to humans. Efficient Pb immobilization using P amendments requires increasing the solubility of the phosphate phase and of the Pb species phase by inducing acid conditions. Although phosphorus addition seems to be highly effective, excess P in soil and its potential effect on eutrophication of surface water, and the possibility of As enhanced leaching remains a concern. The use of mixed treatments may be a useful strategy to improve their effectiveness in reducing lead phyto- and bioavailability.  相似文献   

18.
Ultramafic and volcanic soils are exploited for industrial activities such as mining due to their high metal content, thus it is important that species in these areas are documented before irreversible environmental damage sets in. In this study, aerial and ground leaf litter, dead vines and twigs from six forest patches on volcanic and ultramafic soils in the provinces of Bataan, Pangasinan and Zambales in the Philippines were cultured in moist chambers (MC) and assessed for myxomycete diversity. From the 77% positive MC for myxomycetes, a total of 40 species from 14 genera were identified. Despite the higher heavy metal content, forest patches on ultramafic soils had greater species diversity as compared to volcanic soils. In this study, 10 species were abundant in both forest patches, namely Arcyria cinerea, Diachea leucopodia, Diderma effusum, D. hemisphaericum, Didymium ochroideum, Perichaena chrysosperma, P. corticalis, P. depressa, P. dictyonema and Physarum melleum. Selected myxomycetes tested for Cr and Mn content had equal or higher heavy metal levels than that of their leaf substrate. The study hypothesised that the presence of Mn7+ in fruiting bodies of myxomycetes was due to the phagocytosis of food bacteria inhabiting the substrates on the forest soil laden with heavy metal.  相似文献   

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