氯化铵对小白菜产量品质及土壤性质的影响

Effects of Application Rates of Ammonium Chloride on Yield and Quality of Chinese Cabbage-Pak-Choi and Soil Property

通过小白菜盆栽试验 ,研究了 3种氯化铵用量 (即每千克土壤分别施用 0 .2 5 ,0 .5 0 ,0 .75 g氯化铵 )对小白菜产量、可溶性糖和硝酸盐含量以及土壤理化性质的影响 .结果表明 ,合理施用氯化铵 ,小白菜产量增加 ,可溶性糖含量上升 ,且小白菜体内硝酸盐含量随氯化铵用量增加而降低 .试验中所有处理的小白菜鲜样的硝酸盐 ( NO3 - )含量均在 4 3 2 mg/ kg以下 ,符合食用硝酸盐控制标准 .氯化铵的最高施用量以 3 75 kg/ hm2左右为宜 .随着氯化铵用量的增加 ,土壤中氯离子残留量增加 ,氯离子含量不超过 3 0 0 mg/ kg时 ,小白菜能正常生长 ,过量施用氯化铵可导致小白菜氯中毒 .施用氯化铵后土壤 p H值下降 0 .4 8～ 1.0 9,且土壤 p H值下降幅度有随氯化铵用量增加而增大的趋势 .土壤铵态氮含量随着氯化铵用量的增加而增加 ,土壤硝态氮含量则与之相反 ,但都比对照高 .施用氯化铵能够增加土壤阳离子交换量 .随着氯化铵用量的增加 ,土壤中粒径小于 0 .0 0 5 mm和小于 0 .0

The pot experiments on quaternary period red soil and alluvial soil were conducted to study the effects of application rates of ammonium chloride on the yield and quality of chinese cabbage pak choi and soil properties.The results show that the yield and the contents of soluble sugar in chinese cabbage pak choi remarkably increase with the appropriate application of ammonium chloride, but the nitrate contents decrease with the increase of ammonium chloride.The suitable rate is 375 kg/hm 2.The Cl - accumulates in soil and pH descends by 0.48~1.09 unite after the application of ammonium chloride.chinese cabbage pak choi grow normally when Cl - in soil is less than 300 mg/kg but is poisoned by the over application of ammonium chloride.The NH 4 +-N,cation exchange capacity,and microaggregates that include ○/ <0.005 mm and ○/ <0.01 mm increase insignificantly with the application of ammonium chloride.However,NO 3 --N shows opposite result.