| 题名 | 准噶尔荒漠生物结皮中微生物分布格局及生态功能 |
| 作者 | 吴楠 |
| 学位类别 | 博士 |
| 答辩日期 | 2008 |
| 授予单位 | 中国科学院．新疆生态与地理研究所 |
| 导师 | 张元明，中国科学院新疆生态与地理研究所 |
| 关键词 | 微生物分布格局 |
| 其他题名 | Distribution patterns and ecological function of microorganism in biological soil crusts in Junggar Desert |
| 中文摘要 | 本文以微生物这一生物结皮中的先锋物种为突破口，开展微生物学、生态学、土壤学等多学科交叉研究，内容涉及生物结皮中微生物的时空分布特征、动物干扰对微生物分布的影响、结皮恢复过程中土壤生态因子分异特征、寡营养菌的理化特性及固沙功能探析、生物结皮富集有机质、固定氮素的生态功能等。主要研究结果包括： 1、该沙漠生物结皮中，细菌占绝对数量优势，依次为放线菌、真菌。微生物的生态分布对地貌部位有较强的选择性（垄顶<坡部<垄间低地）。沙垄多数部位微生物数量在春季多于秋季。微生物垂直分布复杂，垄顶和垄间低地垂直分布格局明显不同。 2、微生物各类群对践踏干扰的反应具差异性，真菌最敏感。 3、啮齿类动物的洞穴是微生物（尤其是真菌）繁殖的良好场所。 4、结皮恢复过程中，微生物总数量呈现递增趋势，细菌能够分泌大量黏性的胞外多糖有效黏结沙粒，放线菌、真菌的菌丝体能够有效地捆绑沙粒，有机质与土壤酶活性呈现良好的相关性,促进了结皮演替。 5、获得了一株能在生物结皮中起到固沙及保水作用的寡营养杆状细菌。 6、生物结皮强烈影响地表0-5cm土层有机质的积累。 7、生物结皮的固氮活性在6-10月间最高，进入11月显著降低。不计风蚀、水蚀等对氮素造成的损耗，该沙漠生物结皮年固氮量理论估算值为4.36×106Kg。Focused on the pionner component (microorganism) in BSC, this study was conducted to investigate the temporal-spatial variability of microorganism relating to locations, soil layers of sand dune, seasons, soil variables and disturbances.Under laboratory and field conditions, we analyzed the role of microbes in BSC structure and function. The main conclusions are followded as: 1、Among different microorganism groups, bacteria were predominant, actinomyces the next and fungi the least. Microorganisms showed the highest capabilities of settlement and growth in interdune. It seemed that spring created comfortable conditions for microbes. The vertical distribution patterns of soil microorganism was different in the top of sand dunes and interdunes. 2、The response of each group of microorganisms to grazing disturbance was varied. Fungi were much more sensitive to grazing disturbance. 3、The burrow system constructed by the great gerbil were likely to be favorable environments for microorganism, especially fungil. 4、The association between soil variables and recovery time was more obvious. Total quantity of microognisms showed the consistent trend . Exopolysaccharides excreted by bacteria served as agents providing sand stabilization .Sand grains also entrapped by fungal filaments. Activity of soil enzymes had distinct positive linear correlation with soil organic matter. All the above promoted the rovery of BSC. 5、A oligotrophic bacteria which could created a lot of mucopolysaccharide to help BSC structure was isolated. 6、BSC could influence the accumulation of soil organic matter in the surface 0- 5cm soil layer . 7、The results suggest that nitrogenase activity (NA,nmolC2H4m－2h－1) for each type of crusts were highly variable. All crust types had highest NA During June to October and lowest NA from November to next February. Regardless losses, the BSC of Gurbantunggut Desert are expected to fix 4.36 ×106KgN year－1. |
| 语种 | 中文 |
| 学科主题 | 微生物学 |
| 公开日期 | 2010-11-12 |
| 页码 | 共194页 |
| 内容类型 | 学位论文 |
| 源URL | [http://ir.xjlas.org/handle/365004/8016]  |
| 专题 | 新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据) |
| 推荐引用方式 GB/T 7714 | 吴楠. 准噶尔荒漠生物结皮中微生物分布格局及生态功能[D]. 中国科学院．新疆生态与地理研究所. 2008. |
| 个性服务 |
| 查看访问统计 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
修改评论