【作者】 亢连强；

【导师】 马耀光； 齐学斌；

【作者基本信息】 西北农林科技大学 ， 农业水土工程， 2007， 硕士

【摘要】 为地下水埋深不同地区再生水的安全高效利用提供理论依据,本试验在地中渗透仪中进行,用马氏瓶控制地下水位分别为2m、3m、4m,取污水处理厂的再生水灌溉冬小麦和夏玉米,并与清水对照,对其各项生育指标变化及灌水前后氮素运移进行了研究,结果表明:1、再生水灌溉有利于冬小麦叶面积指数、干物质积累量和产量的增加,与清水相比,能为作物提供更多的营养元素。相同灌水量和施肥条件下,低水处理冬小麦产量与地下水埋深成指数相关,高水处理产量与地下水埋深为多项式关系。从冬小麦各生育指标、干物质积累量、产量和水分利用效率分析得出,地下水埋深为2m的地区,再生水灌溉选用低水处理较好;地下水埋深为3m和4m的地区,再生水灌溉选用高水处理较好。2、地下水位埋深对夏玉米的叶面积指数影响较大,叶面积指数随着地下水位埋深的增加而减小,其中4m地下水位对叶面积指数的影响最大。灌水量相同时,低水处理和高水处理的夏玉米产量与地下水埋深都为多项式关系;地下水埋深相同时,高水灌溉的产量比低水灌溉的大。3、灌水前和灌水后,土壤的硝态氮含量都是先随深度增加而增大,在达到一个峰值后,再随深度增加而减小。与灌水前相比,灌水后硝态氮含量的峰值都出现下移现象,灌水前峰值出现在20~40cm土层处,灌水后峰值出现在40~80cm处,说明灌水对表层土壤的硝态氮有强烈的淋洗作用。4、灌水后0~200cm土壤的硝态氮平均含量升高,地下水埋深相同时,高灌水量处理增加的硝态氮含量比低灌水量处理的增加值大;灌水量相同时,土壤中硝态氮增加量和地下水中硝态氮的增量与地下水埋深成多项式关系。更多还原

【Abstract】 The aim of the article is to provide theoretical foundation for safe and efficient utilization of reclaimed water in the areas of different depths of groundwater. The experiment is made in the lysimeter, and the groundwater tables are 2m, 3m and 4m controlled by Mariotte. In the experiment, the reclaimed water acquired from sewage treatment plant is used to irrigate winter wheat and summer corn, and the variation of all indexes and nitrogen transportation of the wheat and corn are studied. The results are as following:1. The reclaimed water irrigation greatly affects the leaf area index, the dry matter accumulation and the output of the winter wheat. Under the same condition of irrigation amount and fertilization, the output of winter wheat with low water treatment has the exponential correlation with groundwater table, and the output of winter wheat with high water treatment has the polynomial correlation with groundwater table. Low water handling is better for reclaimed water irrigation in the areas of groundwater depth of 2m through analyzing the physiological indexes, the dry matter accumulation, the output and the water use efficiency. In the meantime, high water handling is better for reclaimed water irrigation in the areas of groundwater depth of 3m and 4m.2. The leaf area index of summer corn is affected by the groundwater depth, and it decreases with the groundwater depth raising. The groundwater depth of 4m has the most significant influence. Under the same condition of irrigation amount and fertilization, the output of summer corn with low or high water treatment has the polynomial correlation with groundwater table. And under the same condition of groundwater, the output with high water treatment is more than the output with low water treatment.3. The nitrate nitrogen content of soil firstly increases along depth direction, and after getting to a summit decreases along depth direction, no matter before irrigation or after irrigation. Compared with the time before irrigation, the summit of nitrate nitrogen content after irrigation shifts down, from the summit on the soil layer of 20-40cm before irrigation to the summit on the soil layer of 40-80cm after irrigation, which illustrates that irrigation has the dramatically leaching influence to nitrate nitrogen of surface soil. 4. The average content of nitrate nitrogen on the soil layer of 0-200cm has increased after irrigation. And with the same groundwater depth, the increasing of nitrate nitrogen content of high water handling is more than low water handling, because the more irrigation amount contains more nitrogen. With the same irrigation amount, the increasing of nitrate nitrogen content both in the soil and groundwater has the polynomial correlation with groundwater table.更多还原