Knowledge Resource Center for Ecological Environment in Arid Area
| 增水、升温和氮添加对古尔班通古特沙漠植被、 土壤养分及气态氮素损失的影响 | |
| 其他题名 | Effects of simulated nitrogen deposition，precipitation, and warming on plant，soil nutrient and nitrogen gaseous loss in the Gurbantunggut Desert |
| 吴文超 | |
| 出版年 | 2018 |
| 学位类型 | 硕士 |
| 导师 | 刘学军 ; 李凯辉 |
| 学位授予单位 | 中国科学院大学 |
| 中文摘要 | 摘 要气候变暖、降水格局和大气氮沉降是近年来人们非常关注的全球变化，它们能够影响植物群落生长、土壤养分以及气态氮素损失。然而，以前的研究大部分集中在森林与草原生态系统，目前有关干旱半干旱区荒漠生态系统如何对增温、降水和氮沉降增加响应的研究相对较少。荒漠生态系统降雨少，干旱高温，土壤含氮量低，与其它生态系统相比，增温、降水和氮沉降增加有可能带来更大的生态效应。因此，为探究大气氮沉降、降雨和气候变暖对温带沙漠植物群落、土壤养分和气态氮素损失（NH3，N2O）的影响，2014年9月到2018年6月在古尔班通古特沙漠开展了基于降水、氮沉降和增温相结合的多因子控制实验。结果如下：（1）水、氮添加均增加荒漠植物群落多样性和生产力，但不显著；增温提高了植物群落多样性而降低了生产力，但均不显著；水氮添加具有显著交互作用，减少了植物群落多样性但增加了生产力。植物群落生产力与多样性显著负相关。荒漠草本植物群落对增水响应比较敏感，且在增水的基础上，氮添加和升温对其更敏感；菊科和十字花科植物比牻牛儿苗科和禾本科植物对水氮更敏感，牻牛儿苗科和菊科植物对升温比较敏感。 （2）氮添加显著增加了土壤有机碳和全氮，但显著减少了土壤全磷和全钾；水添加和增温均对土壤有机碳和全氮没有显著影响，但显著降低了土壤中磷钾的含量；水氮添加对土壤氮磷有显著的交互作用。土壤化学计量比主要受控于土壤C和N，土壤C比N更为缺乏。水添加、氮添加均显著降低了土壤pH值，但增温显著增加了土壤pH值；水氮温三因素对土壤电导率整体上均没有显著影响。古尔班通古特沙漠土壤MBC/MBN比值介于1.52～4.34，表明在古尔班通古特沙漠土壤微生物群落中细菌占据优势。（3）氮添加显著促进土壤氨挥发，增水和升温均对其影响不显著，水氮对土壤氨挥发有明显的交互作用，水氮温整体上促进显著土壤氨挥发。荒漠土壤氨挥发有显著的季节性变化，荒漠土壤氨挥发在春季波动较大，夏秋季较为规律。土壤温湿度在春季显著影响氨挥发，夏季土壤pH抑制土壤氨挥发，土壤氨挥发随土壤铵态氮、植物群落生物量和多样性先增后减。氮添加显著促进土壤N2O排放，增水和升温增加N2O排放但不显著，水氮温整体上促进显著土壤N2O排放。氧化亚氮具有明显的季节性变化，在春季土壤湿度与N2O通量显著负相关；在夏秋季，土壤湿度，铵根含量与N2O排放显著正相关而土壤pH与其负相关；土壤氧化亚氮通量随植物群落生物量和多样性均先增后减。关键词：氮沉降；降水；增温；物种多样性；土壤养分；氮素损失; 古尔班通古特 |
| 英文摘要 | AbstractGlobal warming, precipitation patterns, nitrogen（N）deposition have become heated issues of global change in recent years, which could affect the plant growth, soil nutrient and N gaseous loss. However, most previous studies focused on the forest and grass ecosystems. Few researches were reported in desert ecosystems. Due to less precipitation, lower N concentration in soil, drought and high temperature, increasing temperature, precipitation and nitrogen deposition in desert ecosystems would lead to greater effects compared to other ecosystems. Therefore, to understand the effects of atmospheric nitrogen deposition, precipitation and global warming on plant, soil nutrient and and N gaseous loss in temperate desert ecosystem, a field multiple-factor experiment including increased precipitation, nitrogen addition and increasing temperature was conducted in the Gurbantunggut Desert from Sept.2014 to May.2018. The main results are summarized as follows:（1）Water or N addition increased plant biodiversity and productivity and increasing temperature increased plant productivity but biodiversity, which were not significant; Significant interaction effects of water and N addition on plant biodiversity and productivity were found. Water and N addition enhanced plant productivity but reduced their productivity, non-significantly. Plant biodiversity negatively correlated with plant productivity. Desert plants community were sensitive to water addition. Based on the condition of precipitation, N addition and increasing temperature have more sensitive effects on desert plants community. Compositae and Brassicaceae species were more sensitive to water or nitrogen addition compared with Geraniaceae and Grass species, while increasing temperature affected sensitively Geraniaceae and Compositae species.（2） In general, N addition increased soil organic carbon（SOC）and total nitrogen（TN）but decreased total phosphorus（TP）and potassium（TK）, significantly. Water addition and increasing temperature hadn’t significant effects on SOC and TN, while the contents of TK was cut significantly down. The interactive effect of water and N addition on TN and TP can be found. Soil stoichiometric ratios were largely mediated by the contents of SOC and TN, and SOC was more limited than TN in the Gurbantunggut Desert. Water or N addition decreased soil pH, while soil pH was improved by increasing temperature. Increasing temperature, water or N addition did not affect significantly soil electrical conductivity (EC). Owing to the ratio of MBC to MBN ranging from 1.52 to 4.34, our results suggest that the bacteria hold advantage in the soil microbial community in the Gurbantunggut Desert.（3）N addition promoted significantly soil ammonia volatilization that was not affected significantly by water addition and increasing temperature. Obvious interaction effects on soil ammonia volatilization was observed, Increasing temperature, water and N addition accelerated significantly soil ammonia volatilization as a whole. Soil ammonia volatilization showed obvious seasonal variations: variations of ammonia volatilization in spring was more fluctuated than that of summer and autumn. Temperature and moisture of soil had significant effects on soil ammonia volatilization in spring; ammonia volatilization was suppressed by soil pH in autumn. Moreover, soil ammonia volatilization being firstly increased and then decreased was accompanied by soil NH4+-N, plant communities biomass and diversity. N addition tended to increase significantly N2O emissions in treatments compared with those in control, increasing temperature and water addition accelerate slightly soil N2O emissions. Increasing temperature, water and N addition promote significantly N2O emissions as a whole.The N2O emissions presented large seasonal variations in the study area. Soil humidity negatively correlated with the fluxes of N2O in spring.The content of soil NH4+-N and soil humidity had significant positive correlation with the fluxes of N2O while soil pH negatively correlated with that of N2O; the N2O emissions being firstly increased and then decreased was accompanied by plant communities biomass and diversity.Key words: nitrogen deposition；precipitation；species diversity；soil nutrient； nitrogen gaseous loss；temperate desert |
| 中文关键词 | 氮沉降 ; 降水 ; 增温 ; 土壤养分 ; 氮素损失 |
| 英文关键词 | nitrogen deposition precipitation soil nutrien nitrogen gaseous loss |
| 语种 | 中文 |
| 国家 | 中国 |
| 来源学科分类 | 环境工程 |
| 来源机构 | 中国科学院新疆生态与地理研究所 |
| 资源类型 | 学位论文 |
| 条目标识符 | http://119.78.100.177/qdio/handle/2XILL650/288164 |
| 推荐引用方式 GB/T 7714 | 吴文超. 增水、升温和氮添加对古尔班通古特沙漠植被、 土壤养分及气态氮素损失的影响[D]. 中国科学院大学,2018. |
| 条目包含的文件 | 条目无相关文件。 | |||||
| 个性服务 |
| 推荐该条目 |
| 保存到收藏夹 |
| 导出为Endnote文件 |
| 谷歌学术 |
| 谷歌学术中相似的文章 |
| [吴文超]的文章 |
| 百度学术 |
| 百度学术中相似的文章 |
| [吴文超]的文章 |
| 必应学术 |
| 必应学术中相似的文章 |
| [吴文超]的文章 |
| 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。
