基于土柱模拟研究水肥模式对马铃薯田氮平衡的影响

发布时间：2018-04-29 05:04

本文选题：土柱 + 水肥模式　；参考：《内蒙古农业大学》2017年硕士论文

【摘要】：农田中氮肥的过量使用对环境造成的污染日趋严重,目前我国的氮肥的利用率远远低于世界平均水平。为了探索农田氮素淋溶损失给环境带来的危害,更加直观且准确地研究氮素养分平衡情况,本试验采用了土柱模拟的方法,以马铃薯田的水肥模式为研究对象,深入探讨了农田生态系统中养分平衡情况,为提高养分利用减少环境污染提供理论依据。为切合实际,实验方案采取了农户调查的方式,从调查中的大户、合作社和公司各选出2个具有代表性的体系进行模拟。通过对试验中马铃薯植株、土壤残留以及马铃薯生长的苗期、块茎形成、块茎膨大和淀粉积累期的淋溶液中氮素养分的测定,得出以下结果:(1)马铃薯植株收获后,不同水肥模式中的土壤残留氮素没有显著差异。滴灌体系的淋溶液总量为471mL,为灌溉量的19.6%,喷灌体系的淋溶液总量为886mL,为灌溉量的25.8%;在施氮量大致相同的情况下,滴灌体系的无机氮的淋失量2.2～4.5 mg之间,喷灌体系的无机氮淋失量在7.7～14.2 mg之间,表明滴灌较喷灌可以提高水分利用率,减少氮素淋失量。(2)施加有机肥可以提高土壤肥力,增加马铃薯植株的吸氮量,降低农田氮素淋溶损失。(3)随着马铃薯植株生长时期的推移淋溶液中氮素的浓度表现为下降的趋势,苗期氮素淋失情况严重,表明基施中应降低氮肥的投入,从而减轻环境压力。(4)不同水肥模式的每个土柱氮平衡在149～375 mg之间变动,表明氮素投入量大于氮素输出量,处于盈余的状态,可能会造成硝酸盐淋溶的问题。
[Abstract]:The environmental pollution caused by the excessive use of nitrogen fertilizer in farmland is becoming more and more serious. At present, the utilization rate of nitrogen fertilizer in China is far lower than the world average level. In order to explore the environmental harm caused by nitrogen leaching loss in farmland and to study the nitrogen nutrient balance more intuitively and accurately, the soil column simulation method was adopted in this experiment, and the water and fertilizer model of potato field was used as the research object. The nutrient balance in farmland ecosystem was discussed in order to provide theoretical basis for improving nutrient utilization and reducing environmental pollution. In order to be practical, the experimental scheme adopts the method of peasant household investigation. Two representative systems are selected from the large households, cooperatives and companies in the survey to simulate the experiment. Through the determination of nitrogen nutrients in potato plant, soil residue, seedling stage of potato growth, tuber formation, tuber enlargement and starch accumulation stage, the following results were obtained: 1) after harvest of potato plant, There was no significant difference in soil residual nitrogen between different water and fertilizer models. The total amount of leaching solution in drip irrigation system was 471mL, which was 19.6mg of irrigation amount, and the total amount of leaching solution in sprinkler irrigation system was 886mL, which was 25.8mL.The leaching amount of inorganic nitrogen in drip irrigation system was between 2.2 mg and 4.5 mg under the condition of similar nitrogen application. The amount of inorganic nitrogen leaching in sprinkler irrigation system was between 7. 7 and 14. 2 mg, which indicated that drip irrigation could increase water use efficiency and reduce nitrogen leaching loss.) applying organic fertilizer could improve soil fertility and increase nitrogen uptake of potato plants. Reduction of nitrogen leaching loss in farmland. 3) with the increase of potato plant growth stage, nitrogen concentration in the solution showed a decreasing trend, and nitrogen leaching loss in seedling stage was serious, which indicated that the input of nitrogen fertilizer should be reduced in basal application. Therefore, the nitrogen balance of each soil column of different water and fertilizer models varied from 149 to 375 mg, indicating that nitrogen input was larger than nitrogen output and was in surplus state, which might cause nitrate leaching.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S532

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