华北菜地硝酸盐淋失调控研究

发布时间：2024-03-29 19:51

　　氮肥在农业生产中具有重要作用。氮肥的大量施用导致氮(NH3,NO3,NO,N2O,N2)的损失增加。氮(N)可以显著地提高作物的产量和品质。为满足作物生长需求,农业生产中氮肥的投入增加,进而造成N的额外损失。为此,相关农业部门修订了氮肥的使用标准。但由于N的固有损失,特别是硝酸盐淋溶,导致氮肥利用效率仍低于50%。近几十年来,由于采用现代施肥技术,中国农业生产能力大幅提高。然而,中国高产区的氮肥利用效率仍低于35%,硝酸盐的淋溶损失是氮素损失的主要途径之一。硝酸盐和粘土颗粒都携带负电荷,因此粘土颗粒不能长时间吸附硝酸盐,硝酸盐被根际区域以外的水溶解并随之移动,即为硝酸盐的淋溶。大量的研究表明硝酸盐淋溶对地下和地表水质有负面的影响。氮肥的增施还造成蔬菜中硝酸盐浓度的增加,从而对人类健康产生不利影响。许多专家指出,硝酸盐的淋溶以及蔬菜中硝酸盐的积累引起人类对健康问题的担忧。硝酸盐与高铁血红蛋白血症有关,还有许多目前尚无定论的人类健康问题,如癌症(通过细菌产生N-亚硝基化合物)、高血压、中枢神经系统出生缺陷、糖尿病、自然流产、呼吸道感染和免疫系统异常变化等。此外,在少数情况下,硝酸盐的大量消...

【文章页数】：148 页

【学位级别】：博士

【文章目录】：
摘要
abstract
Abbreviations
CHAPTER-1 INTRODUCTION
    1.1 FACTORS AFFECTING NITRATE LEACHING
        1.1.1 Soil Properties
        1.1.2 Land Management
        1.1.3 Climatic Factors
        1.1.4 Management Practices
    1.2 NITRATE LEACHING MEASUREMENT METHODS
        1.2.1 Model Application
        1.2.2 Suction Cup and Lysimeter
        1.2.3 Repeat Soil Core Method
        1.2.4 Nitrate Leaching Measurement Approaches
    1.3 STAPLE ISOTOPIC TECHNIQUES
    1.4 RESEARCH BASIS
        1.4.1 Literature Review
        1.4.2 Problem Statement
        1.4.3 Research Targets
        1.4.4 Research Aims
        1.4.5 Purpose of the Study
        1.4.6 Significance of Study
CHAPTER-2 EXPERIMENTS DESIGN SPECIFICATIONS
    2.1 INTRODUCTION
    2.2 EXPERIMENT DESIGN
    2.3 EXPERIMENT PROCEDURE
    2.4 LYSIMETER DESIGN SPECIFICATIONS
    2.5 SOIL COLLECTION AND SAMPLING
    2.6 MOISTURE CONTENT SENSOR CALIBRATION
    2.7 LABORATORY ANALYSIS
        2.7.1 Soil pH
        2.7.2 Soil EC
        2.7.3 Soil Bulk Density
        2.7.4 Flow Injection Analysis
        2.7.5 ¹⁵N Nitrate Analysis
        2.7.6 ¹⁵N Ammonia Analysis
CHAPTER-3 MINERAL N IN SOIL PROFIL
    3.1 EXPERIMENT PROCEDURES
    3.2 SITE SPECIFICATIONS
    3.3 STATISTICAL ANALYSIS
    3.4 RESULTS
        3.4.1 Soil pH Variations
        3.4.2 Soil EC Variations
        3.4.3 Soil Nitrate Variations
        3.4.4 Soil Ammonium Variations
        3.4.5 Total Plant Available Nitrogen
        3.4.6 Total Yields
    3.5 DISCUSSIONS
CHAPTER-4 VEGETABLE PLANTATION AND NITRATE LEACHING
    4.1 EXPERIMENT DESIGN AND SPECIFICATIONS
    4.2 SITE DETAILS
    4.3 EXPERIMENT PROCEDURE
    4.4 LABORATORY ANALYSIS
    4.5 STATISTICAL ANALYSIS
    4.6 RESULTS
        4.6.1 ¹⁵N Recovery in Dry Matter
        4.6.2 ¹⁵N in Leachate
        4.6.3 ¹⁵N in Soil
        4.6.4 Evapotranspiration and Inches Per Feet
        4.6.5 Total Nitrogen and Tracer Uptake
        4.6.6 Total Leachate Volume Total and Tracer N in Nitrate
        4.6.7 Total and Tracer Ammonia in Leachate
        4.6.8 Water Use Efficiency ¹⁵N and ¹⁴N Uptake
        4.6.9 Plant Growth Curve
        4.6.10 Total Mineral and ¹⁵N Leached
        4.6.11 Soil Properties
        4.6.12 ¹⁵N Balance
    4.7 DISCUSSIONS
CHAPTER-5 NITRATE LEACHING IN NORTH CHINA PLAIN FROM VEGETABLE CROPS
    5.1 FACTORS AFFECTING NITRATE LEACHING
    5.2 NCP SOIL PROPERTIES
        5.2.1 Soil Physical Properties
        5.2.2 Soil Chemical Properties
    5.3 CLIMATIC FACTORS
    5.4 LAND USE MANAGEMENT
        5.4.1 Vegetable Crops in Open Field
        5.4.2 Vegetable Crops in Protected Greenhouses
    5.5 RECOMMENDATIONS
CHAPTER-6 CONCLUSION
REFERENCES
APPENDIX
ACKNOWLEDGEMENTS
RASHEED AHMED(RESUME)



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