6种蔬菜对施用含砷禽畜粪土壤中砷的吸收

由于现代集约化养殖业普遍使用有机胂制剂,禽畜粪中往往含有一定的砷(As).在水稻土中分别以2%和4%(w/w)比例施入含As鸡粪和猪粪及无机肥(N:0.2g·kg-1;P2O5;0.1g·kg-1;K2O:0.15g·kg-1(以干土计)),以不施肥为对照进行菜心、小白菜、油麦、茼蒿、苋菜和通菜6种蔬菜盆栽试验,研究比较含As禽畜粪施入土壤后蔬菜对土壤中As的吸收累积情况.结果表明,1)整体上施用鸡粪处理蔬菜生物量高于无机肥处理,而施用猪粪处理除通菜外5种蔬菜生物量均低于无机肥处理.2)施肥可降低除通菜外的5种蔬菜As含量,而施用鸡、猪粪可显著提高通菜As含量.3)菜心、小白菜、油麦和茼蒿地上部As含量与其生物量呈显著负相关(p<0.05,p<0.01);苋菜也表现为负相关,但未达到显著;通菜则表现为显著正相关(p<0.01).4)菜心、小白菜、油麦和茼蒿As吸收量整体表现为施用鸡粪>无机肥>猪粪≈不施肥;苋菜表现为无机肥>不施肥>鸡、猪粪;通菜则表现为鸡、猪粪>无机肥≈不施肥.整体上通菜As吸收量高于其他5种蔬菜.5)施肥可降低除通菜外5种蔬菜As吸收系数,而施用鸡、猪粪可显著提高通菜As吸收系数.建议含As禽畜粪在通菜上尽量少施.

As Uptake by Six Vegetables Grown in Paddy Soil Applied Animal Manures Containing As

Since organic arsenic additives are commonly used in modern intensive poultry and livestock production, animal manure often contains arsenic (As). In order to investigate the As uptake by vegetables grown in soil spiked with animal manures containing As, 6 vegetables, including flowering Chinese cabbage, Chinese cabbage, lettuce, crown daisy, amaranth and water spinach were used to conduct a pot experiment in paddy soil applied 2% and 4% (w/w) chicken manure (CM1, CM2), pig manure (PM1, PM2) containing As and inorganic fertilizer (IF, N:0.2g·kg-1;P2O5:0.1g·kg-1; K2O:0.15g·kg-1), respectively. Soil without any fertilizer was included as the control (CK). Results showed that, 1) Generally, application of the CM increased vegetable yields, while the PM decreased them except for water spinach, as compared with the IF treatment. 2) The As concentrations in the 5 vegetables except water spinach were decreased by fertilization, and the two manures increased the As concentrations in water spinach. 3) The As concentrations in flowering Chinese cabbage, Chinese cabbage, lettuce and crown daisy had significant negative correlations with their biomass (p<0.05, p<0.01); amaranth had negative but not significant correlation with its biomass; water spinach had significant positive correlation with its biomass (p<0.01). 4) As uptake rates in flowering Chinese cabbage, Chinese cabbage, lettuce and crown daisy decreased in the order CM>IF>PM≈CK, and those in crown daisy were IF>CK>CM, PM, while those in water spinach were CM, PM>IF≈CK. 5) Fertilization could decrease As uptake coefficients of vegetables except water spinach. And the two manures could significantly increase As uptake rates and uptake coefficients of water spinach. Therefore, animal manures containing As should not be heavily applied to water spinach.