中文摘要：

通过盆栽试验和室内分析,研究了小白菜对不同含量的外源硒酸盐和亚硒酸盐动态吸收的差异,并通过土壤有效硒及生物量的动态变化探究其产生的原因,旨在为富硒作物的生产和硒污染土壤的植物修复提供理论依据.结果表明,硒酸盐和亚硒酸盐处理小白菜地上部分生物量间无显著差异.在小白菜的整个生长期间（8周）,硒酸盐处理小白菜地上、地下部硒含量均随生长逐渐下降,而亚硒酸盐处理小白菜地上、地下部硒含量均随生长逐渐增大.硒酸盐处理地上部硒吸收量显著高于地下部,而亚硒酸盐处理地下部硒吸收量显著高于地上部;且在整个生长过程中硒酸盐处理小白菜硒吸收量是亚硒酸盐处理的2～60倍之多,导致硒酸盐处理土壤中有效硒含量随着小白菜的生长迅速下降,而亚硒酸盐处理土壤中有效硒含量随小白菜的生长略有下降.统计分析表明,硒酸盐处理小白菜体内硒含量与土壤有效硒含量呈显著正相关,地上、地下硒含量与土壤有效硒的相关系数分别为0.901和0.864,而亚硒酸盐处理两者相关性不显著.综合小白菜硒含量和土壤有效硒随生长变化的结果可以得出,小白菜对硒酸盐和亚硒酸盐动态吸收的差异是小白菜对不同价态硒吸收能力和土壤供硒能力综合作用的结果.

英文摘要：

In order to produce selenium-enriched crops and provide a theoretical basis of phytoremediation to selenium contaminated soil,pot experiment and lab analysis were carried out to examine the differences of selenium uptake pattern and bioavailability to pakchoi（Brassica chinensis L.） when amended with selenate and selenite.Meanwhile,dynamic changes of soil available Se was analyzed to explore the reason.The results showed that no significant differences in pakchoi shoot biomass between selenate and selenite treatment were observed.The Se concentration in pakchoi decreased rapidly across time in the selenate treatments,while increased with the growing period in the selenite treatments.For the selenate treatments,the pakchoi shoot Se concentration was significantly higher than that in roots,but the opposite results were found in the selenite treatments.In the whole growth period of pakchoi,Se concentration in selenate treatment was 2-60 times higher of that in selenite treatments.The content of available Se in soil slightly decreased with the growth of pakchoi in the selenite treatments,but it decreased rapidly in the selenate treatments.The significant correlations between soil available Se and Se concentration in shoots and roots of pakchoi was found in selenate treatments,the correlation coefficients were 0.901 and 0.864,respectively.On the contrast,no significant correlation was observed between soil available Se and Se concentration of roots and shoots in selenite treatments.The results indicated that the differences between the Se uptake pattern of selenate and selenite on pakchoi were the comprehensive function of the ability of soil providing Se and crop uptake ability.