长期定位施肥土壤中重金属含量及其络合机制研究

发布时间：2018-03-05 16:10

本文选题：长期定位施肥　切入点：重金属　出处：《南京农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：施肥对农业生产具有十分重要的作用,农作物产量的提高主要靠土壤养分的供给。然而,不合理施肥会导致土壤结构失衡,重金属含量超标,土壤污染加重等问题。因此,研究长期施肥对农业土壤健康状况的影响,在指导农业健康生产、保护农产品安全和土壤污染治理方面具有重要意义。基于长期定位施肥试验(湖南祁阳、沈阳农大、江西进贤、新疆长期试验站、江西鹰潭和吉林公主岭)(20年),本论文主要分析了CK(不施肥)、NPK(施化肥)、NPKM(施化肥+有机肥)、M(施有机肥)四个施肥处理土壤中的Cu,Zn,Cd,Pb,Ni五种重金属元素的全量和生物有效性含量。依据这五种元素全量和生物有效性的规律,运用红外光谱技术(FTIR)、~(27)Al、~(29)Si固体核磁技术结合二维相关光谱(2D COS)分析方法,进一步研究了 Cu,Zn,Cd这三种重金属在土壤水溶性有机物质(DOM)中的络合机制。本论文主要结杲如下:1.对采自全国各地的商品有机肥(共97个)中重金属Cu,Zn,Cd,Pb,Ni全量进行了检测分析,发现商品有机肥中这5种重金属的含量大部分在各自的正常值范围内,有很少的异常值存在;对比国家有机肥标准,发现大部分样品中重金属全量也都符合国家安全标准。2.采用三酸法(HNO_3-HF-HC104)对长期定位点的土壤进行消解,结果发现除新疆长期试验站外,沈阳农大、湖南祁阳、江西进贤、江西鹰潭和吉林公主岭长期试验站有机肥处理土壤中Cu,Zn,Cd全量比CK处理显著升高(p0.05)。其中,沈阳农大长期试验站土壤中Cu,Zn,Cd全量分别升高21.32mg/kg,35.13mg/kg和0.95mg/kg;湖南祁阳长期试验站土壤中Cu,Zn,Cd全量分别升高59.15mg/kg,71.40mg/kg和0.74mg/kg;江西进贤长期试验站土壤中Cu,Zn,Cd全量分别升高14.81mg/kg,106.01mg/kg和0.28mg/kg;江西鹰潭长期试验站土壤中Cu,Zn,Cd全量分别升高9.76mg/kg,20.93mg/kg和0.22mg/kg;吉林公主岭长期试验站土壤中Cu,Zn,Cd全量分别升高16.17mg/kg,30.65mg/kg和0.96mg/kg。而Pb,Ni的全量基本不受施肥处理的影响;湖南祁阳,江西进贤长期试验站有机肥处理的土壤Cu含量均超出国家二级标准;除新疆长期试验站外,其它地区Cd含量均超出国家二级标准。3.采用薄膜梯度扩散技术(DGT)对各长期试验站不同施肥处理土壤中重金属的生物有效性进行检测,结果表明,沈阳农大、湖南祁阳、江西进贤长期试验站NPK处理的土壤中Zn,Pb,Ni生物有效性含量比M处理的显著增高。而吉林公主岭长期试验站NPK施肥处理的土壤中Zn,Ni,Pb有效性比NPKM处理高,Cd有效性含量则是NPKM处理高于NPK处理;江西鹰潭地区除Pb和Ni外,其余有效性含量均表现为M处理土壤高于NPK处理且差异显著,M处理土壤中Cu,Zn和Cd有效性含量比NPK处理分别高1.42μg/L,41.7μg/L和2.46μg/L;新疆地区元素有效性含量很低,均表现为M处理高于NPK处理土壤。4.采用红外光谱(FTIR)、~(27)Al和~(29)Si固体核磁技术,结合2D COS分析方法,研究了重金属在土壤DOM中的络合机制,结果表明,土壤中迁移性较强的组分DOM中,与重金属结合的官能团主要为纳米矿物,其中的可溶性蛋白几乎不与重金属结合;在NPK和M处理的土壤DOM中,起主要络合作用的分别为Si-O(1050~(-1)000cm~(-1))和Si-O-Al(915cm~(-1))官能团;~(27)Al、~(29)Si固体核磁技术进一步证明了在1050~(-1)000cm~(-1)处为Si-O官能团,但在915cm~(-1)处没有对应的红外吸收峰,说明FTIR分析的含Al官能团在该区域中不存在。
[Abstract]:Fertilization plays a very important role in agricultural production, crop yield increase mainly depends on the soil nutrient supply. However, the unreasonable fertilization will lead to imbalance of soil structure, soil heavy metal content exceed the standard, pollution and other issues. Therefore, the effect of long term fertilization on agricultural soil health in agricultural production, health guidance, has important significance the protection of the safety of agricultural products and soil pollution. Based on long-term fertilization (Hunan Qiyang, Jiangxi Jinxian, Shenyang Agricultural University, Xinjiang, Yingtan and Jiangxi long experiment station, Jilin, Gongzhuling) (20 years), this thesis mainly analyzes the CK (no fertilizer), NPK (Shi Huafei), NPKM (chemical fertilizer + organic fertilizer), M (organic fertilizer) four fertilizer treatments in soil Cu, Zn, Cd, Pb, Ni of five heavy metals in total and bio availability of content. On the basis of the five elements in total and the biological effectiveness of law, use red Spectroscopy (FTIR), ~ (27) Al, ~ (29) Si NMR technique combined with two-dimensional correlation spectroscopy (2D COS) analysis method, further study of the Cu, Zn, Cd these three kinds of heavy metals in soil water soluble organic matter (DOM) complex mechanism in the main results. Are as follows: 1. the production of commercial organic fertilizer from all over the country (97 in total) of heavy metals in Cu, Zn, Cd, Pb, Ni content were detected and analyzed, found that the amount of these 5 kinds of heavy metals in commercial organic fertilizer is most in the normal range, there are few outliers exist; compared with the national the organic fertilizer standard, found that heavy metals in most samples total also comply with the national safety standards.2. by acid method (HNO_3-HF-HC104) for long-term point of soil digestion. The results show that in addition to Xinjiang long experiment station, Shenyang Agricultural University, Hunan Qiyang, Jiangxi Jinxian, Jiangxi Yingtan and Jilin Gongzhuling long test station Inorganic fertilizer in soil Cu, Zn, Cd ratio was significantly increased in CK treatment (P0.05). Among them, Shenyang Agricultural Experiment Station long-term soil Cu, Zn, Cd were increased by 21.32mg/kg, 35.13mg/kg and 0.95mg/kg; Hunan Qiyang long experiment station of soil Cu, Zn, Cd were increased by 59.15mg/kg, 71.40mg/kg 0.74mg/kg and Jiangxi Jinxian; long-term experiment station of soil Cu, Zn, Cd were increased by 14.81mg/kg, 106.01mg/kg and 0.28mg/kg; Jiangxi Yingtan long experiment station of soil Cu, Zn, Cd were increased by 9.76mg/kg, 20.93mg/kg and 0.22mg/kg; Jilin Gongzhuling long experiment station of soil Cu, Zn, Cd respectively increased 16.17mg/kg 0.96mg/kg., 30.65mg/kg and Pb, the total capacity of Ni was not affected by fertilization treatment; Hunan Qiyang, Jiangxi Jinxian experimental station of long-term organic fertilizer soil Cu content exceeded the national standard level two; in addition to the Xinjiang long experiment station, other areas Cd The content exceeded the national standard level two.3. by diffusive gradients in thin films technique (DGT) on the long-term fertilization experiment station were detected, the bioavailability of heavy metals in soil. The results show that the Shenyang Agricultural University, Hunan Qiyang, Jiangxi Jinxian station NPK long-term test in soil treated with Zn, Pb significantly increased content of Ni bioavailability compared with M treatment. While the Jilin Gongzhuling experiment station NPK long-term fertilization treatments Zn, Ni, Pb with high effectiveness than NPKM, effective Cd content is higher than NPKM NPK treatment; Jiangxi Yingtan area except Pb and Ni, the validity of the content of M was higher than NPK treatment and soil significant differences in soil Cu, M, Zn and Cd were high effective content of 1.42 g/L NPK, 41.7 g/L and 2.46 g/L; the Xinjiang area content of effective elements is very low, M was higher than that of NPK in soil by infrared spectroscopy (.4. FTIR), ~ (27) Al and ~ (29) Si NMR technology, combined with 2D COS analysis method, studies the complex mechanism of heavy metals in DOM, the results show that the strong group migration in soil DOM, functional groups and heavy metal binding mainly for nano minerals, which almost soluble protein do not combine with heavy metal; NPK and M in soil treated by DOM, the main complexation were Si-O (1050~ (-1) 000cm~ (-1)) and Si-O-Al (915cm~ (-1)) group; (27) ~ Al, ~ (29) Si NMR technology was further proved that the 1050~ (-1 000cm~ (-1)) for Si-O functional groups, but in 915cm~ (-1) infrared absorption peak has no corresponding FTIR analysis, containing Al functionality does not exist in this region.

【学位授予单位】：南京农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53;S153

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