滇池西岸4种针叶林的土壤微生物与酶活性

采用实地调查与室内实验分析相结合,对位于高原湿地滇池西岸森林公园现存4种针叶林:云南松、华山松+云南油杉混交、云南油杉、柏树的林下土壤微生物特征及酶活性进行研究.结果表明:4种针叶林中,土壤微生物数量差异性显著,呈现出从混交林到纯林逐渐减少趋势.在微生物区系组成中,细菌占绝对优势,放线菌次之,真菌最少,且均随着土层的加...     

不同纤维素水平对瘤胃微生物分离获得率及DNA提取率的影响

以3只瘘管山羊为瘤胃液供体,研究体外培养条件下不同纤维素水平底物对微生物的分离获得率及DNA提取率的影响。底物可溶性淀粉与纯纤维素比例设计为：100：0,70：30,50：50,30：70,0：100。结果表明：总微生物分离获得率与DNA提取率随底物纤维素含量的增加,总体上呈现下降趋势;分离获得率为53．29％,总微生物DNA提取率为51．0％;细菌DNA的提取率（45．4％）显著低于原虫DNA的提取率（56．1％）（P〈0.05）;所提得DNA片段在20kb以上,PCR扩增效果较好,适合于后续研究的分子操作。     

转基因作物对土壤微生物多样性影响

土壤微生物的多样性及其活性是保持农业生态系统稳定的基础,而作物的改变对土壤微生物的多样性结构和活性具有显著的影响。转基因作物被引入到农田后所带来的微生物群落的变化及对农业生态系统所带来的不确定因素,已成为研究热点。本文综述了近年来转基因作物对土壤微生物群落影响的研究进展,并且着重介绍了转基因抗虫棉对根际微生物多样性影响的研究进展。     

土壤微生物在促进植物生长方面的作用与发展前景

土壤微生物与植物的根系形成一个稳定的动态系统,在这个系统中它们之间相互作用,相互影响,植物的根系为土壤微生物提供养分,土壤微生物反过来也促进了植物根系的发育,从而促进了植物的生长。本文就土壤微生物生长特性,阐述了土壤微生物对植物的促进作用和应用前景。     

茶-山苍子间作对茶园土壤微生物群落结构的影响

【目的】解析山苍子间作条件下茶园土壤微生物群落结构的变化规律及其影响因素,为茶-山苍子间作的土壤生态效应评估提供数据支撑。【方法】综合运用GC-MS、ICP-MS,以及16S、ITS高通量测序技术分别对土壤浸提液成分、土壤矿质营养元素含量、土壤细菌和真菌种群结构进行测定分析。【结果】间作处理显著改变了土壤微生物种群结构,土壤中参与氮(N)、磷(P)和锰(Mn)等过程的功能性细菌丰度显著增加,植物致病细菌和真菌丰度显著降低,根系分布层具有溶解磷(P)功能的伯克氏菌属伯克氏菌丰度是对照的86倍,镰刀菌属镰刀霉丰度比对照降低了73.13%。间作影响了P、铁(Fe)、Mn等土壤矿质营养元素的含量,尤其是P,根系分布层土壤P含量比对照增加76.42%。间作区域土壤分别含有12.80%的樟脑、6.72%的Alpha-松油醇和12.65%的香茅醇等杀菌或抑菌物质。冗余分析表明,间作区域土壤中的樟脑、桉叶油醇、Alpha-松油醇、乙酸冰片酯和香茅醇等次生代谢物与P元素是影响土壤微生物群落结构的主要环境因子。【结论】茶-山苍子间作显著改变了土壤微生物群落结构和丰度,樟脑、Alpha-松油醇和香茅醇等次生...     

Soil bacterial community responses to cadmium and lead stabilization during ecological restoration of an abandoned mine

Ecological restoration refers to the gradual recovery of damaged ecosystems by utilizing their self-recovery capacity and artificial measures. It is considered as an effective technique to alleviate heavy metal pollution in open-pit mining soils. However, little is known about the stability of heavy metals and soil bacterial responses in artificially restored soil-plant systems. In this study, different vegetation restoration strategies were established in the Dabaoshan mining area, China, and the accumulation and transfer of Cd/Pb in the soil-plant system and the responses of the soil bacterial community were investigated. Results showed that ecological restoration with a combination of trees, shrubs and grasses/herbs could increase soil cation-exchange capacity and organic matter content, but not soil pH. The mixture of trees, shrubs and grasses/herbs was most effective for reducing the available Pb content to 33.7% of the content in the control, and the mixture of trees and grasses/herbs was beneficial in reducing Cd to 60.4% of the content in the control. Data showed that ecological restoration could change the quantity, composition and community structure of soil microorganisms. The soils in which a mixture of trees, shrubs and grasses/herbs were grown had the greatest abundance and diversity of bacteria; the abundances of Proteobacteria increased by 12% and Actinobacteria by 5% from those of the control. Plant coverage, soil available Cd content, and organic matter emerged as major determinants of bacterial community composition. This study demonstrates a promising remediation strategy for limiting Cd/Pb mobility in mining areas.     

氯苯、对硝基酚对土壤生物活性的影响

本文通过对土壤呼吸强度，各微生物生理群的数理以及土壤酶活性的测定，研究了氯苯，对硝基酚对土壤生物活性的影响。实验表明氯苯，对硝基酚对土壤活性的影响是复杂的。氯苯在２００ｍｇ／ｋｇ以下对土壤呼吸强度，细菌放线菌及真菌的数量都有一定的刺激作用；而对氨化细菌硝化细菌以及反硝化细菌则表现出抑制作用；     

基于16S rRNA高通量测序的野生和养殖多鳞白甲鱼肠道微生物群落组成研究

为研究多鳞白甲鱼肠道微生物菌群组成及其多样性,采用16S rRNA高通量测序对野生多鳞白甲鱼以及养殖成年健康多鳞白甲鱼肠道内容物进行微生物测序及信息分析.结果表明:不同环境多鳞白甲鱼肠道内容物样品间OTU个数具有一定差别.多鳞白甲鱼肠道菌群主要包括:变形菌门(Proteobacteria)、梭杆菌门(Fusobacte...