中国生态农业学报Issue(2)：218-225,8.DOI:10.13930/j.cnki.cjea.151111
外加氮源在 Cd 超标菜地上的应用效果
Effects of nitrogen addition on above-standard Cd-contaminated soils in vegetable fields
摘要
Abstract
The aim of this study was to explore the effects of nitrogen application on Cd uptake by different kinds of leafy vegetables and on soil available cadmium (Cd) content in above-standard Cd-contaminated soils in vegetable fields. The study also comprehensively evaluated the effects of different nitrogen sources application with the aim of developing strategies to reduce Cd concentration in leafy vegetables by managing the application of nitrogen fertilizers. The experiment was carried out in an above-standard Cd-contaminated vegetable soil to investigate the effects of urea [CO(NH2)2], calcium nitrate [Ca(NO3)2], ammonium nitrate (NH4NO3) and ammonium bicarbonate (NH4HCO3) on yield, quality, Cd content, nitrogen content of two kinds of leafy vegetables — Brassica chinensis L. (BC) and Amaranthus mangostanus L. (AM). Soil DTPA-Cd content and pH as well as comprehensive effects of nitrogen addition on two vegetables were also investigated. The results showed that all nitrogen sources increased yields and decreased Cd contents in both shoot and root systems of the two leafy vegetables. Furthermore, the highest increase of BC yield (59.7%) was caused by NH4HCO3 treatment, while the largest increase of AM yield (47.5%) was caused by CO(NH2)2 treatment, respectively, compared with control. However, the lowest Cd contents in two kinds of leafy vegetables were observed under Ca(NO3)2 treatment among all nitrogen treatments. Ca(NO3)2 decreased Cd content by 41.6% and 24.2%, respectively, in AM shoot and root, by 32.2% and 25.9%, respectively, in BC shoot and root. Moreover, the total content of Cd, nitrate, nitrite, Vitamin C and soluble sugar in the shoot system of the two kinds of leafy vegetables varied with the application of different nitrogen resources. Also similar variances were noted for the changes in soil pH and DTPA-Cd content. NH4NO3 application decreased soil pH by 0.12 and 0.25 and increased soil DTPA-Cd content by 15.3% and 14.6%, respectively, in AM and BC. However, the reverse trend was noted under NH4HCO3 treatment. Comprehensive evaluation results showed that the four kinds of nitrogen resources had much higher synthetic weighted value than that of control. Among all treatments, the highest value was observed in Ca(NO3)2 treatment, which suggested that Ca(NO3)2 had the best comprehensive application effect in above-standard Cd-contaminated soils. Thus Ca(NO3)2 could be used as optimum nitrogen source in above-standard Cd-contaminated soils in vegetable fields.关键词
氮源/菜地/Cd 超标土壤/叶菜/土壤 Cd 有效性Key words
Nitrogen source/Vegetable field/Above-standard Cd-contaminated soil/Leafy vegetable/Availability of soil Cd分类
资源环境引用本文复制引用
王艳红,唐明灯,李盟军,艾绍英,姚建武,罗英健,余丹妮..外加氮源在 Cd 超标菜地上的应用效果[J].中国生态农业学报,2016,(2):218-225,8.基金项目
广东省科技计划项目(2012A030700010)和广州市科技计划项目(2014Y2-00521)资助* Supported by the Science and Technology Planning Project of Guangdong Province (No.2012A030700010) and the Guangzhou Municipal Science and Technology Program (No.2014Y2-00521) （2012A030700010）
