【作者】 张文新；

【导师】 赵同科； 薛世川；

【作者基本信息】 河北农业大学 ， 植物营养学， 2010， 硕士

【副题名】氮素调控技术研究

【摘要】 目前,在我国农业生产中,化肥的使用越来越广,施肥不当所带来的面源污染问题也越来越明显。我国化肥的利用效率较低,一般作物的氮肥仅有30%-35%被有效利用,其余氮肥一部分以挥发或反硝化方式气态损失,另一部分滞留在土壤中,或是在降雨和灌溉作用下,随着地表径流流失,或者随着淋溶进入地下水,从而对水环境造成巨大的影响。开展水源保护区农业面源污染防治技术研究工作意义重大。本文通过对官厅水源保护区农民施肥量、土壤肥力、地下水硝酸盐含量调查研究,利用氮素减控技术和控释肥技术研究大田土壤硝态氮分布运移规律,为定量评估化肥氮素对地下水的潜在危害、提出减少硝态氮淋洗损失措施和制定环境友好的施肥制度提供科学依据。研究主要结论如下：1影响农户的施肥决策因素众多。农户的年龄、文化水平、农资产品的价格、农村组织化程度和农业政策等是影响农户施肥决策的主要因素。在此调查中,农民在追求利润最大化的前提下,重氮肥,轻磷、钾肥现象普遍存在。2 2007年3月延庆小丰营村土壤调查结果显示：蔬菜产区土壤表层有机质、全氮、速效钾和有效磷含量大于玉米区和玉米蔬菜混作区。3 2006-2008年地下水硝酸盐含量调查结果显示：该地区15%左右的地下水为Ⅲ类水,不适宜直接饮用。3年中蔬菜区地下水硝酸盐含量最高,分布在3.24-4.92 mg／L范围内,果树区次之,在2.03-2.25 mg／L范围内,玉米区最低,在1.12-1.21 mg／L范围内。4菜地氮素减控技术在该地区试验结果初步表明,氮肥减量10-30%时的经济产量与常规处理差异不显著；氮素用量与土体硝酸盐含量成正相关,说明氮素减控技术在降低土壤硝酸盐含量及向下淋溶有一定的作用,并具有较好的环境效益。5控释氮肥减少菜田土壤硝酸盐淋溶试验中,树脂包衣处理较常规处理圆白菜增产效果显著；三种缓释氮素在一定时期能够将土壤硝酸盐保持在圆白菜的主要根系层,树脂包衣在圆白菜莲座期、结球期和收获期效果比较稳定,硫包衣和添加DCD氮肥前期效果好,后期淋溶加强。6控释氮肥减少大田土壤硝酸盐淋溶试验中,树脂包衣与硫包衣对春玉米增产效果显著,并且两者显著降低了土壤硝酸盐含量。更多还原

【Abstract】 At present, non-point source pollution which is caused by more and more extensive use of chemical fertilizer and the misuse of fertilizer is more and more manifest in our agricultural production. The utilization efficiency of chemical fertilizer is low in china, only 30%-35%nitrogenous fertilizer of crop is effective used, one part of the rest nitrogenous fertilizer lost by volatilize or the way of nitric, the other part of the rest detained in soil, or lost with surface runoff in rainfall and irrigation, or run into under-water with leaching water, that caused great influence on water environment. Research on the prevention techniques of agricultural non-point pollution in water protection area is of great importance. The text provided scientific evidence for quantitative assessment the potential hazard of nitrogenous fertilizer on the groundwater, proposing measures to reduce the lost of nitrate nitrogen leaching and laying down a environmental friendly system of fertilization. The main conclusion follows:1.There are many decision factor affected farmers’ fertilizer. The main factors are farmers age, and cultural level, agricultural product price, rural organization and agricultural policies. In the investigation, the phenomenon of appreciating of nitrogen fertilizer, contempt of potash fertilizer is widespread under the precondition of pursuit the maximum profit.2.The result which was investigated soil at Xiaofengying Yanqing county at March 2007 showed that the content of organic substances, total nitrogen, available phosphorus, available phosphorus at vegetable plot are more than corn plot and the mixed area of corn and vegetable plot.3.The result which was investigated the content of nitrate in groundwater from 2006 to 2008 showed that about 15% groundwater which is III type of water is unfit for direct drink. The content of nitrate in groundwater of vegetable plot is on the top in this three years, which distributed at 3.24-4.92 mg/L, the follow is fruit tree plot, which distributed at 2.03-2.25 mg/L, corn plot is the lowest, which distributed at 1.12-1.21 mg/L.4.Test results of using vegetable plot nitrogen control techniques in the area indicated that there was no significant difference between nitrogen of reducing 10% to 30% and normal treatment on economic yield, nitrogen content and soil nitrate content are positive correlation, the results indicated that nitrogen control techniques had a certain role on reducing nitrogen leaching down and reducing the content of soil nitrate, and it had better environmental benefits.5.In the test of reducing soil nitrate leaching of vegetable plot using nitrogen control techniques, comparing normal treatment, resin coating can significantly improve economic yield of cabbage; the three kinds of controlled release fertilizer can be keep nitrate in the main root in the cabbage in a certain period, the effects of resin coating is relatively stable at rosette stage, heading stage and harvesting time, sulfur coated and DCD added nitrogen are effective in the early period, leaching is strengthened in the latter period.6.In the test of reducing soil nitrate leaching of vegetable plot using nitrogen control techniques, resin coating and sulfur coated had a significant role on economic yield of spring corn, and both reduced the content of soil nitrate significantly.更多还原