作者机构：
[Tian, Qingshan; Huang, Yunxiang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Wang, Peng] China Haohua North Chem, 19 Xiaoying Rd, Beijing 100101, Peoples R China.;[Zhang, Bo; Jiao, Wentao] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, 18 Shuangqing Rd, Beijing 100085, Peoples R China.
通讯机构：
[Bo Zhang; Yunxiang Huang] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, No. 18 Shuangqing Road, Haidian District, Beijing 100085, China
摘要：
<jats:p>Uranium and arsenic are two pollutants commonly found in groundwater near uranium mines. However, the reactivity of U(VI) and As(V) need to be carefully investigated to better understand their fate and transport in the environment. In this study, the reactivity of U(VI) and As(V) were studied under various pH, bicarbonate, and Ca2+ levels. In air-equilibrated systems, the reactivity of U(VI) and As(V) generally decreased with the increase in pH, as evidenced by the solubility of U(VI) and As(V) increasing along with the elevation of pH. At pH = 8, 44.70% and 37.81% of initially added U(VI) and As(V) remained soluble. The addition of 1 mM of bicarbonate increased the reactivity of U(VI) and As(V) at mild acidic to neutral pH; however, the presence of bicarbonate significantly increased the solubility of U(VI) at mild alkaline condition, as nearly all U(VI) remained soluble at pH values of 8 and 9. After the addition of Ca2+, the solubility of both U(VI) and As(V) decreased at mild acidic to neutral pH ranges; however, the addition of Ca2+ markedly increased the soluble percentages of U(VI) at neutral pH, in which the condition 97.81 ± 2.95% of U(VI) remained soluble. Comparatively, only 36.13 ± 4.98% and 1.69 ± 1.08% of U(VI) were soluble at the same pH in air-equilibrated and bicarbonate systems. Our study demonstrated that U(VI) and As(V) are less reactive at neutral to alkaline conditions. Furthermore, the addition of bicarbonate and Ca2+ can further reduce the reactivity of U(VI) and As(V) at neutral to alkaline conditions. The findings of this study contribute to a deeper understanding of the fate and transport of U(VI) and As(V) in groundwater and could aid in better designing of U(VI) and As(V) removal processes.</jats:p>
作者机构：
[黄运湘; 杨蕾静; 黄煌; 于康; 欧阳宁相] College of Resources and Environmental Science, Hunan Agricultural University, Changsha, 410128, China;Xiangxi Station of Soil and Fertilizer, Jishou, 416000, China;[龙怀玉] Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China;[向艳艳] College of Resources and Environmental Science, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>Xiangxi Station of Soil and Fertilizer, Jishou, 416000, China
关键词：
菠菜;负压灌溉;生物产量;根系活力;水分利用效率
摘要：
为筛选出南方地区菠菜生长最适宜的灌溉负压值,采用土壤盆栽试验,以人工浇灌为对照（CK）,研究3个供水负压（-5.0,-10.0,-15.0 k Pa）对菠菜生长、生理指标、品质指标、水分利用效率及养分吸收的影响.结果表明:-5.0 kPa负压供水,菠菜地上部产量178.2 g/pot,显著高于-10.0和-15.0 kPa,与CK差异不具有统计学意义;地下部生物量9.99 g/pot,显著高于CK和-15.0 k Pa;根系活力419.0μg/（g·h）,显著高于CK,-10.0和-15.0 k Pa,分别提高65.3%,51.5%和91.0%; VC和可溶性糖含量分别为0.507 2 mg/g和1.74%,较CK,-10.0和-15.0 k Pa分别提高18.3%,10.5%,44.9%和6.1%,23.4%,47.5%.-5.0 k Pa负压供水,水分利用效率为3.89 g/kg,显著高于CK和-15.0 k Pa,与-10.0 k Pa差异不具有统计学意义;菠菜地上部氮的累积吸收量显著高于CK,-10.0和-15.0 k Pa,磷、钾累积吸收量与CK差异不具有统计学意义,但显著高于-15.0k Pa.综合菠菜产量和水分利用效率,-5.0 k Pa负压供水较适合南方地区菠菜生长发育.
摘要：
为探明负压灌溉条件下小白菜生长发育的适宜负压和土壤含水量,采用土壤盆栽试验结合负压灌溉技术,研究2种土壤（潮菜园土、红菜园土）和3个供水负压（-5.0 k Pa、-10.0 k Pa、-15.0 k Pa）对小白菜生长发育及生理指标的影响。结果表明,小白菜生物产量和根系活力在2种供试土壤条件下均以-5.0 k Pa处理最高,随着供水负压值的降低,生物产量和根系活力显著下降;脯氨酸含量以-10.0 k Pa处理最高,显著高于-5.0k Pa和-15.0 k Pa处理;水分利用效率以-5.0 k Pa处理最低,显著低于-10.0 k Pa和-15.0 k Pa处理。综合小白菜生物产量、水分利用效率及对不同供水负压的生理响应,2种供试土壤适宜小白菜生长发育的供水负压值为-5.0 k Pa,土壤含水量潮菜园土为25%,红菜园土为19%。
摘要：
为筛选出南方冬季蔬菜小白菜（brassica）主动式供水灌溉（负压灌溉）最适宜的土壤水分条件,采用盆栽试验,研究了南方地区2种典型蔬菜土壤—红菜园土和潮菜园土,3个不同负压给水（-5.0、-7.5、-10.0 k Pa）对土壤含水率、小白菜生长情况、耗水特性及其水分利用效率等的影响。结果表明,红菜园土种植冬季小白菜,最适宜的负压灌溉值为-10.0 k Pa,土壤质量含水率为18.7%,潮菜园土最适宜的负压灌溉值为-5.0 k Pa,土壤质量含水率为25.3%。
