不同材料对河套灌区土壤氮磷钾素淋溶特征分布的影响

发布时间：2018-03-29 17:54

本文选题：河套灌区　切入点：土壤养分　出处：《内蒙古农业大学》2017年硕士论文

【摘要】：在提高肥料利用率和保证粮食作物稳效高产前提下,降低肥料养分淋失,减轻农业化肥面源污染,是协调粮食资源和环境问题的根本[1]。内蒙古河套灌区农作物种植集约化程度高,但因不合理施肥导致的农业面源污染也较为严重。化肥养分淋失是河套灌区肥料养分损失的主要途径,但养分淋失动态特征和控制治理技术措施尚未引起足够重视[4]。因此,本文于2015-2016年,针对河套灌区化肥面源污染存在的关键问题,从污染物源头治理,研究探讨河套灌区肥料养分淋溶特征及其所造成的农业面源污染治理技术措施研究具有重要的科学价值和实用意义。本文通过田间试验分别布置了 9个处理3次重复,探讨了河套灌区农田在不同材料处理情况下,作物整个生育期内土壤水中氮、磷、钾素以及PH的淋溶动态分布特征,对其进行定性定量分析。以常规施肥为对照,利用田间小区试验,对土壤水养分淋失控制措施进行了系统研究,取得以下主要研究结果:(1)土壤水氮素随着淋溶层增加呈现先下降后升高趋势,具体表现为0～20cm20～40cm80～100cm40～80cm;在0～100cm淋溶层土壤水氮素浓度与施肥量呈正相关关系,其中以N03--N的流失最为严重;不同材料处理情况下,聚丙烯酰胺、膨润土、活性炭、聚丙烯酸钾处理效果显著,聚丙烯酰胺较常规处理总氮浓度平均下降24.14%,可溶性氮平均下降14.42%,硝态氮平均下降28.71%,铵态氮平均下降17.62%;膨润土较常规处理总氮浓度平均下降22.48%,可溶性氮浓度平均下降15.49%。(2)土壤水磷素随着淋溶层增加呈现下降趋势,磷素移动性较小,不易从土壤耕作层向深处淋溶,磷素主要集中在0～40cm;在不同材料处理情况下,膨润土、活性炭、聚丙烯酸钾、聚丙烯酰胺处理效果显著,可有效降低土壤水磷素浓度,平均降低21.47%;颗粒有机肥处理在作物苗期较常规处理磷素平均浓度提高38.43%,而农学生产效率较常规处理偏低,说明并非施肥量越大,农作物产量约高。(3)土壤水中K+易随土壤水淋溶发生迁移,可淋溶到100cm 土层以外,K+浓度随土壤淋溶层深度的增加而递减,0～20 cm层钾离子含量达到最大值,且呈倒置的"S"形分布;在不同材料处理情况下,膨润土、活性炭、聚丙烯酰胺、聚丙烯酸钾处理效果显著。综合考虑不同材料对土壤水氮、磷、钾素以及PH淋溶特征分布的影响,其中聚丙烯酰胺、膨润土、活性炭、膨润土处理效果显著,有机肥显著增加磷素含量,缓控肥处理能够保证养分的持续释放从而有利于作物吸收,腐殖酸处理与常规处理比较土壤水氮、磷、钾含量没有显著变化。
[Abstract]:On the premise of increasing fertilizer utilization efficiency and ensuring stable and high yield of grain crops, the leaching loss of fertilizer nutrients and the non-point source pollution of agricultural chemical fertilizers were reduced. It is the foundation of coordinating food resources and environment problems [1] .Inner-Mongolia Hetao Irrigation area has a high degree of intensive crop cultivation, But the agricultural non-point source pollution caused by unreasonable fertilization is also serious. Fertilizer nutrient leaching is the main way of fertilizer nutrient loss in Hetao irrigation area, but the dynamic characteristics of nutrient leaching and the technical measures of controlling nutrient loss have not been paid enough attention to [4]. This paper aims at the key problems of chemical fertilizer non-point source pollution in Hetao Irrigation District from 2015-2016. It is of great scientific value and practical significance to study the leaching characteristics of fertilizer nutrients and the technical measures of agricultural non-point source pollution control in Hetao Irrigation area. The leaching dynamic distribution characteristics of nitrogen, phosphorus, potassium and PH in soil water during the whole growth period of crops in Hetao irrigation area were studied. The control measures of soil water nutrient leaching were studied systematically by field plot experiment. The following main results were obtained: the nitrogen content of soil water decreased first and then increased with the increase of leaching layer. The results showed that the nitrogen concentration of soil water in 0~100cm leaching layer was positively correlated with the amount of fertilizer application, in which the loss of N was the most serious, and the treatment effect of polyacrylamide, bentonite, activated carbon and potassium polyacrylate was remarkable under different materials treatment. Compared with the conventional treatment, the average total nitrogen concentration of polyacrylamide decreased 24.14%, the soluble nitrogen decreased 14.42 2%, the nitrate nitrogen decreased 28.71%, the ammonium nitrogen decreased 17.62%, the bentonite decreased 22.48% and the soluble nitrogen concentration decreased 22.48%. The content of phosphorus in soil water decreased with the increase of leaching layer. Phosphorus mobility is small, it is not easy to leach from soil ploughing layer to deep, phosphorus is mainly concentrated at 0 ~ 40 cm, bentonite, activated carbon, potassium polyacrylate and polyacrylamide are effective in different materials treatment. The average concentration of phosphorus in soil water decreased by 21.47, and the average concentration of phosphorus in granular organic fertilizer treatment increased 38.43 in seedling stage, but the agricultural production efficiency was lower than that in conventional treatment. The K content in soil water tends to migrate with soil water leaching, and K concentration can be leached to the soil layer outside 100cm soil layer, which decreases with the increase of the depth of the soil leaching layer, and the K ~ + content in the layer of 20 cm is the maximum, and the K ~ + content in the soil water reaches the maximum value, and it is distributed in an inverted "S" shape. The effects of bentonite, activated carbon, polyacrylamide and potassium polyacrylate on the leaching characteristics of soil water, nitrogen, phosphorus, potassium and PH were considered. Bentonite, activated carbon, bentonite treatment have remarkable effect, organic fertilizer can significantly increase phosphorus content, slow control fertilizer treatment can ensure the sustained release of nutrients, which is conducive to crop absorption. Humic acid treatment compared with conventional treatment soil water, nitrogen, phosphorus, There was no significant change in potassium content.
【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】：S153

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