土壤氮素是影響作物生產(chǎn)的重要因素。傳統(tǒng)農(nóng)業(yè)高度依賴于化肥,但所施用的氮肥中,只有<55%的氮素可以被作物吸收,其他的氮素通過淋溶、氣體排放等途徑從農(nóng)田流失,造成土壤退化和環(huán)境污染。作物生長無可避免地受到病蟲草害等生物脅迫的影響。盡管殺菌劑、殺蟲劑和除草劑等農(nóng)藥的使用,可以控制病蟲草害,但也會提高病原體、昆蟲和雜草物種的耐藥性,并增加作物生產(chǎn)成本。這些農(nóng)業(yè)生產(chǎn)問題在加拿大西部大平原上格外突出。因此,通過改進(jìn)農(nóng)業(yè)生產(chǎn)方式來提高氮肥利用效率和降低生物脅迫日益受到人們的重視。豆科作物具有較好的生物固氮功能,輪作可以有效地防治田間病蟲草害。本研究設(shè)想,把豆科作物的固氮功能和輪作的生物防治功能相結(jié)合,將豆科作物安排進(jìn)輪作系統(tǒng)中,既可以減少氮肥的使用量、提高氮肥利用效率又能降低田間生物脅迫。但是,輪作中過少地安排豆科作物,提高氮肥利用效率的效果有限,而過多地安排同一種豆科作物卻會增加田間病蟲草害并影響豆科作物自身的生長。那么,在一個輪作系統(tǒng)中,究竟怎樣安排豆科作物,才能既有利于豆科作物自身的生長,又能提高輪作系統(tǒng)中非豆科作物的生長和整個輪作系統(tǒng)的綜合生產(chǎn)力和效益呢?為此,本研究依托于一個從20... 

【文章來源】：甘肅農(nóng)業(yè)大學(xué)甘肅省

【文章頁數(shù)】：147 頁

【學(xué)位級別】：博士

【文章目錄】：
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
致謝
導(dǎo)師簡介


【參考文獻(xiàn)】：
期刊論文
[1]好氣和厭氧條件下小麥秸稈的腐解特征研究[J]. 王景,陳曦,張雅潔,郜紅建.  中國農(nóng)業(yè)大學(xué)學(xué)報. 2015(03)
[2]自毒作用與連作障礙[J]. 張曉玲,潘振剛,周曉鋒,倪吾鐘.  土壤通報. 2007(04)
[3]設(shè)施蔬菜連作障礙原因綜合分析與防治措施[J]. 吳鳳芝,趙鳳艷,劉元英.  東北農(nóng)業(yè)大學(xué)學(xué)報. 2000(03)



本文編號：2986334