【作者】 白丽静；

【导师】 张克强；

【作者基本信息】 中国农业科学院 ， 环境工程， 2010， 硕士

【摘要】 近年来畜禽养殖业迅速兴起,产生大量废水,与直接排放到地表或地下水体相比,应用废水进行农田灌溉被认为是最有效的资源再利用方式。猪场废水回灌农田不仅能满足作物对水分的需求,同时还是很好的肥源。依据田间试验寻求不同的灌水量和灌水时期对冬小麦-夏玉米轮作体系中作物产量的影响,传统方法费时且不经济,本文选用Root Zone Water Quality Model（RZWQM,根区水质模型）综合评价灌水量和灌水时期对土壤-作物系统的影响。根据2007年9月-2008年9月在天津市西青区杨柳青镇益利来养殖场内开展的田间试验,用厌氧水与地下水1:1混水灌溉处理(灌水定额830 m3 ha^-1)的土壤剖面体积含水量、硝态氮含量以及作物产量等数值对模型进行了率定,用中量厌氧水灌溉处理(灌水定额500 m3 ha^-1)和厌氧水与地下水1:5混水灌溉处理(灌水定额830 m3 ha^-1)的数据对模型进行了验证。在模型率定和验证的基础上,针对平水年降雨数据,用RZWQM对猪场废水灌水量和灌水时期进行了优化,得到模拟年份的较优灌溉模式。通过模拟和预测过程发现,水分模拟值整体反映了实测值的变化趋势,0-60 cm土层模拟结果较好;土壤剖面各土层硝态氮含量模拟值基本反映了实测值的变化,处理二的模拟结果较好,各处理不同生育期100 cm土层硝态氮累积量的模拟结果比较理想;小麦和玉米产量模拟情况良好,RE基本都控制在±16%以内,玉米生物量模拟情况良好,小麦生物量模拟值普遍比实测值偏低;针对不同的灌溉组合,也得到了几种较优的灌溉模式:（1）厌氧水与地下水1:5混水灌溉时,在冬小麦越冬期和拔节期灌溉两次水就能获得较高产量,灌水量为830 m3 ha^-1,小麦产量为5625 kg ha^-1,玉米产量为8403 kg ha^-1,玉米收获后0-100cm土层硝态氮含量为85.18 kg ha^-1; （2）厌氧水与地下水1:1混水灌溉时,在冬小麦-夏玉米整个生育期灌溉一次带有养分的水源就能保证作物的正常生长,在拔节期灌溉700 m3 ha^-1的1:1厌氧水,越冬和抽穗期灌溉830 m3 ha^-1的地下水为推荐的灌溉模式,可获得小麦产量5625 kg ha^-1,玉米产量8403 kg ha^-1,玉米收获后0-100cm土层硝态氮含量为97.20 kg ha^-1;（3）为省去稀释灌溉操作过程中的繁琐,也可推荐厌氧水直接灌溉,在小麦越冬期灌溉300 m3 ha^-1的厌氧水、在拔节和抽穗期分别灌溉830 m3 ha^-1的地下水或在小麦越冬和拔节期分别灌溉830 m3 ha^-1的地下水、抽穗期灌溉400 m3 ha^-1的厌氧水也可获得较高的产量,玉米收获后0-100cm土层硝态氮含量也在环境安全允许的范围内。总体来说,RZWQM可用于模拟猪场废水灌溉对土壤剖面体积含水量、硝态氮含量以及作物产量的影响,同时能较准确预测灌水量和灌水时期对作物产量和土壤中硝态氮含量的影响。更多还原

【Abstract】 In recent years, livestock and poultry breeding industry has developed rapidly but generate a great amount of wastewater. Compared with directly discharging into earth’s surface or groundwater body, using the wastewater for farm irrigation is the most effective way of resources recycling. Swine wastewater, irrigated back to the farmland, not only provides water for the crop, but also is a good fertilizer source. On the basis of field tests, seeking for the effect of different irrigating amount and period on crop yield in winter-wheat and summer-maize rotation system, conventional methods are expensive and time consuming. In this study, the Root Zone Water Quality Model （RZWQM） was used to overall evaluate the effects of irrigating amount and period on soil-plant system.Field experiments were carried out from September, 2007 to September, 2008, in Yililai breeding farm of Yang Liuqing Town, Xiqing District, Tianjin. First, the model was calibrated using the data of volumetric water contents in the soil profile, nitrate-N contents, crop production of the Tanae:gw1:1 treatment(quota=830 m3 ha^-1), then the model was validated with the data of the TManae(quota=500 m3 ha^-1)and Tanae:gw1:5 treatment (quota=830 m3 ha^-1). Finally, based on the calibration and validation, optimizing wastewater amounts and periods with RZWQM, relatively better irrigation modes of the simulated year were got.Through the course of simulation and prediction, the results were shown that simulated values of soil water reflected the variation tendency of measured values on the whole, 0-60 cm soil layer was better. And simulated values of nitrate-N contents in each layer of soil profile basically reflected the variation of measured values. The simulated result of the TManae treatment was better in the three treatments. The simulated results of nitrate-N cumulants in the 0-100cm soil layer in different growth periods of each treatment were relatively better. The simulated yields of winter-wheat and summer-maize were in good consistence with the measured ones, with RE basically controlled into±16% interval. The simulated values of maize aboveground biomass were unanimous with the measured ones, but the simulated values of wheat aboveground biomass were less than the measured ones. Towards different irrigation combinations, several better irrigation modes were got as follows: （1） Irrigate with the anae:gw1:5 water, two irrigations with irrigation quota of 830 m3 ha^-1 for the winter wheat at wintering stage and jointing stage respectively could obtain 5625 kg ha^-1 for winter wheat and 8403 kg ha^-1 for summer maize, the content of nitrate-N in 0-100 cm soil layer was 85.18 kg ha^-1 after corn harvest; （2） Irrigate with anae:gw1:1 water, groundwater irrigation quota of 830 m3 ha^-1 for the winter wheat at wintering stage and heading stage respectively, 700 m3 ha^-1 anae:gw1:1 water only at jointing stage also could obtain 5625 kg ha^-1 for winter wheat and 8403 kg ha^-1 for summer maize, the content of nitrate nitrogen in 0-100 cm soil layer was 97.20 kg ha^-1 after corn harvest; （3） for omitting the trouble during the course of dilute anaerobic water, groundwater irrigation quota of 830 m3 ha^-1 for the winter wheat at jointing stage and heading stage respectively, and 300 m3 ha^-1 anaerobic water only at wintering stage; or groundwater irrigation quota of 830 m3 ha^-1 for the winter wheat at wintering stage and jointing stage respectively, and 400 m3 ha^-1 anaerobic water for irrigation only at heading stage, both of the above two schemes could obtain more yields. After corn harvest, nitrate-N contents in 0-100 cm soil layer were also in permitted extent of environmental safety. Overall, RZWQM was applicable of simulating the effect on crop production, water contents and nitrate-N contents in soil profiles under swine wastewater irrigation. Meanwhile, the model was also used to exactly predict the influence of irrigating amount and period on crop yields and nitrate-N contents in the soil.更多还原