【作者】 林芬芳；

【导师】 王果；

【作者基本信息】 福建农林大学 ， 土壤学， 2006， 硕士

【摘要】 本论文在调查了福建省8个县、区的20多个蔬菜品种和相应表层土壤的含铜状况的基础上，研究了土壤铜的有效度及其影响因素和铜在土壤-蔬菜体系中的转移规律。主要结果如下： 1、采样区表层土壤全铜含量变化在1.68～184.13mg．kg^-1之间，平均值为53.28mg．kg^-1。52.1％的供试土壤样品的全铜量低于国家土壤环境质量标准二级标准中铜的限量(pH＜6.5，农田＜50mg．kg^-1)。 2、对DTPA、EDTA和HCl三种浸提剂的提取效果进行比较的结果表明，（pH7.3）DTPA-CaCl₂-TEA是酸性土壤有效铜的最合适的浸提剂。本研究建立的DTPA提取有效铜的条件是：液土比10：1，振荡速度210转／分，振荡时间120分钟。以该法测定的供试土壤样品有效铜的含量变化在0.50mg．kg^-1～33.36mg．kg^-1之间，平均为6.39mg．kg^-1，有效度（有效铜含量／全铜含量）在1.5％～68.9％之间，平均为1209％，85.6％的样品含铜量＞2mg．kg^-1，说明供试土壤铜供应能力很强。 3、蔬菜可食用部分铜含量（鲜基）在0.09-3.31mg．kg^-1之间，均低于国家食品卫生标准，表明供试蔬菜并未遭受明显铜污染。 4、大部分供试蔬菜品种可食用部分铜含量与土壤全铜含量未表现显著正相关，只有茭白含铜量与土壤全铜呈显著正相关。蔬菜品种可食用部分铜含量与土壤有效铜含量相关关系也不显著，这可能是土壤有效铜以外的因素（如：生长状况、施肥管理水平、气候条件、土壤性质等）对蔬菜吸收铜的影响超过了土壤有效铜的影响。土壤-蔬菜铜转移系数随着土壤全铜含量、土壤有效铜含量的升高而降低，转移系数与土壤全铜或有效铜之间的关系大部分可以用幂方程（y=ax^b）进行描述。 5、根据供试土壤的全铜与有效铜含量范围，我们在全铜=50mg．kg^-1、有效铜=5mg．kg^-1这两个浓度点上分别估算了土壤-蔬菜铜的代表性转移系数（全量基和有效量基），并以有效量基转移系数(TF_DTP5)为依据，将供试蔬菜对土壤铜的富集能力分为如下三类： 低富集蔬菜：转移系数＜0.1，包括萝卜、包菜、小白菜、黄瓜、大蒜、大白菜、芥蓝菜、花菜。 中富集蔬菜：转移系数0.1-0.2，包括西红柿、葫瓜、芹菜、茄子、四季豆、丝瓜、莲藕、春菜、芥菜、茭白、豇豆、苦瓜。 高富集蔬菜：转移系数＞0.2，包括空心菜、芋、韭菜。更多还原

【Abstract】 The availability of soil copper, the factors influencing the Cu availability, and the transfer characteristics of Cu from soil to the edible parts of various vegetables were studied based on an investigation carried out over 8 counties in Fujian province. The main results were as follows:1. The total Cu contents of the surface soils （≤15cm） ranged between 1.68 and 184.13mg.kg^-1 with an average of 53.28mg.kg^-1. The total Cu concentrations of 52.1% of the soils studied were lower than the Cu limits for agricultural land in the China soil environmental quality standard (pH<6.5, farmland<50mg.kg^-1), implying that the soils in these regions have more or less been polluted by copper.2. DTPA-CaCl₂-TEA （pH7.3） was chosen for extracting the available Cu of the soils because it was found to be the best for available Cu extraction for acid soils than the others, HC1 and EDTA. However, the extraction conditions were modified according to our preliminary study as follows liquid:soil= 10:1, shaking time=120 minutes, shaking velocity=210rpm. The available Cu of the soils varied from 0.50 to 33.36 mg.kg^-1 with a mean of 6.39mg.kg^-1. The available degree of the soil Cu （the ratio of the available Cu concentration to the total Cu concentration） varied from 1.5% to 68.9% with a mean of 12.9%.3. The Cu contents （fresh weight basis） of various kinds of vegetables ranged between 0.09 and 3.31 mg.kg^-1. The Cu concentrations of all the vegetables were lower than the limit of the China food hygiene standard, indicating that the vegetables produced in these regions were quite safe for cosumption.4. The Cu concentrations in the edible parts of most of the vegetables species did not significantly correlated with both the soil total and available Cu, which may be attributed to the effects of the factors other than the soil Cu status, such as gowth characteristics, fertilization, agricultural managements and climate. Soil-to-plant transfer factors of Cu （total Cu based or available Cu based） decreased with the increase of soil total Cu and available Cu, most of which can be best described by exponential equation （y=ax^b） .5. According to the ranges of the total and available Cu of the soils used in this study, the representative Cu accumulation index of each vegetable were estimated based on the regression equations between the transfer factors and the soil total Cu or available Cu at the concentrations of 20mg.kg^-1（total Cu） and 5mg.kg^-1（available Cu）, respectively. All the vegetable species studied were grouped into three categaries更多还原