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1.
贾维姝 《安徽农学通报》2010,16(23):204-205,67
列举了国内图书馆联盟发展的几个典型案例,针对联盟成员馆发展不均衡、缺乏有效的组织领导和资金技术支持等存在的现实问题,提出了相应的对策。  相似文献   
2.
The study reports diversity of arbuscular mycorrhizal fungal (AMF) species in the rhizosphere of an endangered anticancerous herb – Curculigo orchioides Gaertn. in its natural habitat. A total of 18 species of AMF, belonging to three genera (Acaulospora, Glomus and Gigaspora) were recorded, with Glomus microcarpum being the most abundant species type. The AMF species composition across the study sites appeared to be influenced by soil pH rather than soil P and vegetation. Acaulospora laevis spores were restricted to sites where the soil pH was acidic. The effectiveness of these native AMF species on growth performance of C. orchioides plants was compared under experimental conditions. In general, the mycorrhizal plants were superior in most of the evaluated parameters, but the extent to which the growth of mycorrhizal plants was influenced varied with the inocula used. The plants inoculated with mixed consortia containing maximum AMF species richness exhibited improved growth in comparison to consortia containing lower AMF diversity and monospecies cultures. The variable plant responses observed with any two consortia having same species richness in the present study could be due to variable component AMF species and their relative abundance. These results emphasize the need to protect the below-ground diversity of AMF and recommend their usage for restoration practices.  相似文献   
3.
采用田间小区试验和室内低剂量模拟叠加试验相结合的方法,研究低剂量外源混合稀土在黄褐土中积累对土壤微生物主要生理类群的生态效应。结果表明,外源低剂量稀土的持续积累会对土壤氨化细菌、硝化细菌、纤维素分解菌和自生固氮菌产生刺激、抑制、再刺激的交替作用。4种土壤微生物生理类群对混合稀土抑制敏感性依大小排序为:纤维素分解菌>氨化细菌>硝化细菌>自生固氮菌。对田间小区低浓度稀土积累下土壤微生物学数据进行模拟计算,稀土积累对纤维素分解菌、氨化细菌、硝化细菌和自生固氮菌的E C50(半抑制浓度)值分别为7.7~10.9、42.3~74.3、12.1~78.4和30.4~91.2m g·kg-1。稀土积累对参与有机碳转化的细菌类群比对参与氮素转化的细菌类群产生更强的抑制作用,纤维素分解菌可作为稀土积累生态效应的指示菌。由于土壤细菌对土壤生物活性的重要贡献,外源稀土在黄褐土中积累对细菌的安全临界值可以初步确定为10~30m g·kg-1。  相似文献   
4.
A pot experiment was conducted to study the plant growth and fruit yields of cucumber (Cucumis sativus L.) on a greenhouse soil with or without inoculation of arbuscular mycorrhizal fungi (AMFs) and Fusarium oxysporum f. sp. cucumerinum under unsterilized conditions. Two AMF inocula were tested: only one AMF strain Glomus caledonium 90036 and an AMF consortium mainly consisting of Glomus spp. and Acaulospora spp. There were four treatments including no inoculation (control), inoculation with F. oxysporum but without mycorrhizae (FO), inoculation with F. oxysporum and G. caledonium (FO+M1), and inoculation with F. oxysporum and the AMF consortium (FO+M2). Cucumber plants were harvested at weeks 3 and 9 after transplanting. Compared with the control, the FO treatment without AMF inoculation had less biomass both at weeks 3 and 9 (P < 0.05) and had higher incidence of Fusarium wilt and produced no cucumber fruit at week 9. Both FO+M1 and FO+M2 treatments had higher mycorrhizal colonization than the treatments which received no AMF inoculation at week 3 (P < 0.05), but only the FO+M2 treatment elevated plant biomass, decreased the incidence of Fusarium wilt, and improved cucumber yields to the same level as the control at week 9. The results indicated that the AMF consortium could suppress Fusarium wilt of cucumber and, therefore, showed potential as a biological control agent in greenhouse agroecosystems.  相似文献   
5.
论述了图书馆联盟用户管理系统实施项目管理的流程和原则,分析了可能导致用户管理系统失败的因素,以及项目评价流程和意义。  相似文献   
6.
电子资源的联盟采购,是指多个图书馆组织起来,联合采购某种资源,以最少的经费,获取最优价格、最佳服务和最符合需求的资源。介绍了国内外电子资源联盟采购的实践活动,指出目前我国集团采购建设中存在的不足和待改进之处,并提出优化对策。  相似文献   
7.
Nitrate reducing potency of 88 bacterial isolates segregated from marine and brackish water nitrifying bacterial consortia (NBC), generated for activation of nitrifying bioreactors, was confirmed by determining the nitrate reducing capability under aerobic conditions as maintained in nitrifying bioreactors. All the isolates had the potential to be used as bio‐augmentors for activating nitrate dissimilation in recirculating aquaculture system. The existence of nitrate reducers with nitrifiers in NBC and in the reactor configuration negates the requirement of integrating anoxic denitrifying system for effective removal of NO3?‐N. Phylogenetic analyses of representative isolates from each cluster of the dendrograms generated based on phenotypic characterization and amplified ribosomal DNA restriction analysis revealed profound diversity of nitrate reducing bacterial flora in the NBC. They were composed of Streptomyces enissocaesilis, Marinobacter sp., Pseudomonas sp., Microbacterium oxydans, Pelagibacterium halotolerans and Alcanivorax dieselolei from marine NBC and Streptomyces tendae, Nesterenkonia sp., Bacillus cereus, Microbacterium oxydans and Brevibacterium sp. from brackish water NBC. The diversity indices of the consortia were calculated using Mega 5.0, primer 7 and VITCOMIC softwares. Marine NBC exhibited higher Shannon wiener diversity and mean population diversity than brackish water NBC. The study delineated higher species richness and diversity in marine NBC than in its brackish water counterpart, a possible reflection of the higher biodiversity of marine systems, and hence, the former is more promising to be used as start‐up cultures for the activation of nitrifying bioreactors after appropriate acclimatization to the desired salinity.  相似文献   
8.
针对数字图书馆建设中出现的分散分隔问题,提出区域数字图书馆建设,以加强图书馆界的整体性与合作性。并从理论上探讨了区域数字图书馆建设理念、建设原则以及在建设中需要考虑的主要问题。  相似文献   
9.
图书馆联盟用户管理系统项目管理研究   总被引:1,自引:0,他引:1  
论述了图书馆联盟用户管理系统实施项目管理的流程和原则,分析了可能导致用户管理系统失败的因素,以及项目评价流程和意义。  相似文献   
10.
对我国图书馆联盟建设的一些思考   总被引:8,自引:0,他引:8  
在现状调研的基础上,从组织机构、资金来源、联盟功能、标准化建设、法律保障和理论研究等几个方面对我国的图书馆联盟建设进行了分析和阐述。  相似文献   
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