【作者】 钟宁；

【导师】 曾清如；

【作者基本信息】 湖南农业大学 ， 环境工程， 2006， 硕士

【摘要】 过碳酰胺是一种新型精细化工品，也是一种新型氮肥，在国外已得到广泛的应用和开发，而我国对其开发和应用刚刚起步。为考察过碳酰胺对土壤理化性状的影响及去除土壤中有机污染物的作用和潜力，拟将修复与施肥结合，污染治理寓于施肥，为施氮和过碳酰胺应用于环境污染修复提供新的理论依据，特进行了本项目的研究。本文采用室内土培试验等手段，研究了3种酸性土壤和3种碱性土壤中施入过碳酰胺后，短期内对土壤pH值和氨气挥发的影响；并探讨了不同酸碱性质土壤中施入过碳酰胺后，氮素转化及对Al元素活性和几种金属元素（Mn、Cu、Zn、Ca、Mg）有效性的影响，以及过碳酰胺对玉米幼苗生长势的肥力效果；最后，选择2种非离子表面活性剂（Triton X-100、Tween80）及2种氯代烃（三氯甲烷—TCM、四氯乙烯—PCE）作为目标污染物，以过碳酰胺为降解试剂，进行批次试验，观察过碳酰胺对土壤中有机污染物的降解效果。试验结果表明： 1．土壤酸碱性对过碳酰胺水解的影响与过碳酰胺浓度有关。常温下，酸性土壤的pH值在短期内都随着加入过碳酰胺浓度的增大而急剧上升，碱性土壤的pH值却是随着加入过碳酰胺浓度的增加先升高、再降低、然后又升高（P＜0.05）；动态试验表明，pH值上升的现象是短期的，6种土壤pH值达到最大值后缓慢下降，2周后3种碱性土壤的pH就降到比原来更低的水平。 2．氨挥发强度与pH变化同步。在酸性和碱性土壤中，氨气日挥发量都是先从小到大出现峰值，然后又降低；酸性土壤和碱性土壤的氨挥发强度峰值分别约在第7天、第3天出现。在3种酸性土壤中，过碳酰胺的氨挥发总量均略小于尿素，而在3种碱性土壤上，却正好相反。过碳酰胺在6种供试土壤上的氨挥发强度顺序及挥发总量次序与尿素的趋势相同，均为：碱性土＞酸性土。 3．过碳酰胺在土壤中的转化速率与尿素相近。其氮素转化规律是：酸性和碱性土壤中NH₄⁺—N含量和NO₃^-—N含量均与土壤pH变化趋势相似。酸性土壤各处理中NH₄⁺—N含量大约在1-2周后增加到峰值，第4周后NH₄⁺—N含量显著降低，并趋于常量水更多还原

【Abstract】 Percarbamide is an important chemical product and a new fertilizer, widely using in foreign, but just beginning in china. In order to evaluate the effects of percarbamide on the physico-chemical properties of soils and the potential degradation efficiency of organic contamination, the changes of pH, volatilization of Ammonia, percarbamide-N transformation, active Al and other trace elements, and the growth of maize in 3 acidic soils and 3 alkali soils were studied by indoor incubation test; Also the degradation efficiency of two nonionic surfactants (Triton X-100 and Tween80) and two chlorhydrocarbons(trichloromethane TCM, and perchloroethylene PCE ) by percarbamide in one soil was investigated. The results show that:1. Effects of acidity and alkalinity of soils on percarbamide hydrolysis is relative to its concentration. At 25 °C, the changes of pH in acidic soils increased quickly, while the changes of pH in alkali soils increased first, then fell, rose again, with the increasing concentrations of applied percarbamide. The time-course experiment revealed that the increase of soil pH was short-term, a subsequently slow drop after reached their maximum in 6 soils, and pH of 3 alkali soils fell less than original ones after 2 weeks.2. Ammonia volatilization intensity followed the changes of soil pH: rose to maximum, and then fell between 3 acidic soils and 3 alkali soils with different maximum and different time. The maximum of ammonia volatilization intensity in 3 acidic soils and 3 alkali soils was the 7th day and the 3rd day respectively; the initial ammonia volatilization intensity from percarbamide was higher than that from urea in 6 soils, while the total ammonia volatilization quantity of urea peroxide were less than urea in 3 acidic soils, and were little higher than urea in 3 alkali soils. The order of intensity and amounts of ammonia volatilization of percarbamide was similar to更多还原