豆科作物轮作对半干旱地区农作系统氮平衡和生产力的影响

发布时间：2021-01-19 04:25

　　土壤氮素是影响作物生产的重要因素。传统农业高度依赖于化肥,但所施用的氮肥中,只有<55%的氮素可以被作物吸收,其他的氮素通过淋溶、气体排放等途径从农田流失,造成土壤退化和环境污染。作物生长无可避免地受到病虫草害等生物胁迫的影响。尽管杀菌剂、杀虫剂和除草剂等农药的使用,可以控制病虫草害,但也会提高病原体、昆虫和杂草物种的耐药性,并增加作物生产成本。这些农业生产问题在加拿大西部大平原上格外突出。因此,通过改进农业生产方式来提高氮肥利用效率和降低生物胁迫日益受到人们的重视。豆科作物具有较好的生物固氮功能,轮作可以有效地防治田间病虫草害。本研究设想,把豆科作物的固氮功能和轮作的生物防治功能相结合,将豆科作物安排进轮作系统中,既可以减少氮肥的使用量、提高氮肥利用效率又能降低田间生物胁迫。但是,轮作中过少地安排豆科作物,提高氮肥利用效率的效果有限,而过多地安排同一种豆科作物却会增加田间病虫草害并影响豆科作物自身的生长。那么,在一个轮作系统中,究竟怎样安排豆科作物,才能既有利于豆科作物自身的生长,又能提高轮作系统中非豆科作物的生长和整个轮作系统的综合生产力和效益呢?为此,本研究依托于一个从20... 

【文章来源】：甘肃农业大学甘肃省

【文章页数】：147 页

【学位级别】：博士

【文章目录】：
摘要
Summary
Introduction
Chapter1.Literature review
    1.1 Advantages and disadvantages of monoculture and rotation system
    1.2 Soil nitrogen and nitrogen balance in agroecosystem in rotation systems
    1.3 Plant growth and biotic stress control in rotation systems
    1.4 Key methods in evaluating rotation systems
Chapter2.Materials and methods
    2.1 Experimental site
    2.2 Experimental design
    2.3 Crop management
    2.4 Data collection and analysis
Chapter3.Performance of legumes in different rotation systems
    3.1 Soil nitrogen, phosphorus and water content in different rotation systems
    3.2 Plant growth and yield of legumes in different rotation systems
    3.3 Mechanisms for yield improvement of legumes in different rotation systems
    3.4 System robustness in different crop rotations in chickpea production
    3.5 Brief summary
Chapter4.Performance of wheat in different rotation systems
    4.1 Soil nitrogen and water content in wheat fields in different rotation systems
    4.2 Plant growth and yield of wheat in different rotation systems
    4.3 Resource use efficiency and profitability of different rotation systems in wheat production
    4.4 Mechanisms for yield improvement of wheat in different rotation systems
    4.5 Brief summary
Chapter5.Soil nitrogen cycling and nitrogen balance in different rotation systems
    5.1 Nitrogen fixation by legumes in different rotation systems
    5.2 Soil nitrogen content in different rotation systems
    5.3 Nitrogen uptake in crop straws and seeds in different rotation systems
    5.4 Nitrogen loss from different rotation systems
    5.5 Nitrogen balance in different rotation systems
    5.6 Nitrogen use efficiency in different rotation systems
    5.7 Brief summary
Chapter6.Productivity and comprehensive benefits of different rotation systems
    6.1 Overall productivity in different rotation systems
    6.2 Comprehensive evaluation of benefits of different rotation systems
    6.3 Brief summary
Chapter7.Discussion and conclusion
    7.1 Discussion
    7.2 Conclusion
References
附件
致谢
导师简介


【参考文献】：
期刊论文
[1]好气和厌氧条件下小麦秸秆的腐解特征研究[J]. 王景,陈曦,张雅洁,郜红建.  中国农业大学学报. 2015(03)
[2]自毒作用与连作障碍[J]. 张晓玲,潘振刚,周晓锋,倪吾钟.  土壤通报. 2007(04)
[3]设施蔬菜连作障碍原因综合分析与防治措施[J]. 吴凤芝,赵凤艳,刘元英.  东北农业大学学报. 2000(03)



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