论文部分内容阅读
研究重庆4个农贸市场市售3大类19种蔬菜73个样品中硝酸盐含量及重庆市13个主要蔬菜基地土壤和蔬菜的硝酸盐、亚硝酸盐含量及相关性。结果表明,重庆市售蔬菜不同种类及同种蔬菜不同部位的硝酸盐含量差异显著。大小顺序为叶菜类(X=1 619.73 mg/kg)>茄果类(X=1 327.67 mg/kg)>葱蒜类(X=1 078.39 mg/kg);莴苣叶(X=1 567.91 mg/kg)>莴苣茎(X=1 871.62 mg/kg)。叶菜类全部超过了一级标准,污染指数高达9.09,污染程度最为严重;茄果类和葱蒜类超过一级标准的样本占81.3%和87.5%,污染指数分别高达8.85和6.56。重庆市13个主要蔬菜基地不同蔬菜以及同种蔬菜不同部位的硝酸盐含量差异也显著,大小顺序为萝卜叶(X=745.97 mg/kg)>莴苣茎(X=730.88 mg/kg)>莴苣叶(X=693.32 mg/kg)>白菜(X=617.63 mg/kg)>萝卜根(X=575.74 mg/kg)。土壤中NO3--N含量差异也显著,大小顺序为种植莴苣的土壤(X=75.24 mg/kg)>种植白菜的土壤(X=47.05 mg/kg)>种植萝卜的土壤(X=33.42 mg/kg)。蔬菜可食部分的硝酸盐与土壤中的NO3--N含量呈极显著正相关关系,线性方程y=407.872+4.796x。供试重庆市13个主要蔬菜基地土壤及蔬菜可食部分的NO2--N含量均较低且差异不显著,蔬菜中的亚硝酸盐含量和土壤中的NO2--N含量也无显著相关性。
The contents of nitrate and nitrite in soil and vegetables of 13 major vegetable bases in Chongqing were studied. The results showed that there were significant differences in nitrate content in different parts of vegetables and vegetables in Chongqing. The order was leafy vegetables (X = 1 619.73 mg / kg), solanaceous fruits (X = 1 327.67 mg / kg), onion and garlic (X = 1078.39 mg / / kg)> lettuce stem (X = 1871.62 mg / kg). All the leafy vegetables exceeded Grade I with the pollution index as high as 9.09, with the most serious pollution. The samples with more than Grade I of eggplant, onion and garlic accounted for 81.3% and 87.5% respectively, and the pollution index was as high as 8.85 and 6.56 respectively. There were also significant differences in nitrate content between different vegetables and different parts of the same vegetables in 13 major vegetable bases in Chongqing, with the order of radish leaf (X = 745.97 mg / kg)> lettuce stem (X = 730.88 mg / kg)> lettuce leaf (X = 693.32 mg / kg)> cabbage (X = 617.63 mg / kg)> radish root (X = 575.74 mg / kg). The soil NO3 - N content was also significantly different with the order of the soil for planting lettuce (X = 75.24 mg / kg)> the soil for planting cabbage (X = 47.05 mg / kg)> the soil for planting radish (X = 33.42 mg / kg). There was a significant positive correlation between NO3 - N content in the edible part of vegetables and NO3 - N content in soil. The linear equation y = 407.872 + 4.796x. The NO2 - N content of soil and vegetable edible parts of 13 main vegetable bases in Chongqing was lower and the difference was not significant, and there was no significant correlation between the content of nitrite in vegetables and the content of NO2 - N in soil .