摘要
近年来土壤酸化面积不断扩大。土壤酸化后产量下降,肥料效率下降,正在成为制约农业生产的限制因素。我们选取pH5左右的酸化土壤开展调酸剂改良酸化土壤提高磷钾肥肥效的试验研究;选用易获取、价廉以及农户曾经使用过的钙镁磷肥、生石灰和硅钙肥作为调酸剂,以过磷酸钙为对照,大白菜为供试作物,进行小区试验。结果表明,在N300kg/ha、P2O5120kg/ha、K2O150kg/ha施肥水平基础上,施用1500kg/ha硅钙肥,1125kg/ha生石灰或800kg/ha钙镁磷肥,与过磷酸钙对照相比较,都能够显著提高磷钾肥的农学效率。磷、钾肥的农学效率均以施用石灰的最高,分别达到44.0kg/kg^52.7kg/kg,31.9kg/kg^41.7kg/kg;施用调酸剂能够提高白菜可溶性糖含量;钙镁磷肥与过磷酸钙相比较,白菜吸收镉、铅、砷、铬数量没有明显差异,但是随着钙镁磷肥用量的增加,上述重金属的吸收量有同步增加的趋势,这是应用钙镁磷肥等调酸剂改良酸性土壤是应当引起关注的问题;白菜收获后的土壤分析表明,调酸剂处理的土壤pH比过磷酸钙对照高0.94~1.09个单位,效果显著。
With growing areas in soil acidification in recent years,it has resulted in decreased crop yields and fertilizers efficiency.This has increasingly become one of the most important limiting factors in agricultural production in Chongqing.In order to examine effect of different lime materials such as fused calcium-magnesium phosphate(Ca-Mg-P),quick lime and silicon-calcium(Si-Ca)fertilizer on agronomic efficiency of phosphorous and potassium fertilizers,a block experiment was conducted in an acid soil with pH 5.Single superphosphate(SSP)was used as CK,and Chinese cabbage was selected as the target crop.Results showed that on the basis of fertilizer rate at 300-120-150 kg N-P 2 O 5-K 2 O/ha,addition of Si-Ca fertilizer at 1500 kg/ha,and quick lime at 1125 kg/ha or Ca-Mg-P at 800 kg/ha significantly enhanced K agronomic efficiency compared with CK treatment.The highest agronomic efficiencies were achieved as 44.0-52.7 kg/kg for P and as 31.9-41.7 kg/kg for K by using quick lime.Meanwhile application of lime materials increased content of soluble sugar in Chinese cabbage.There were no significant differences in uptake of cadmium,lead,arsenic and chrome by cabbage between Ca-Mg-P and SSP.On the other hand as an increase in rates of Ca-Mg-P,uptake of those heavy metals by cabbage was all increased,indicating it must be cautious when using lime materials such as Ca-Mg-P to acid soils.After-harvest soil analysis revealed that soil pH in the lime treatments was 0.94-1.09 higher than the SSP treatment,a significant effect of lime on soil acidity improvement.
作者
李伟
张宁
周佳
董光群
林国平
Li Wei;Zhang Ning;Zhou Jia;Dong Guangqun;Lin Guoping(Chongqing General Station of Ag-Tech Extension Chongqing 401121;Bishan Station of Ag-Tech Extension Chongqing 402760)
关键词
调酸剂
酸化土壤
大白菜
磷
钾
肥料效应
Lime material
Acid soil
Chinese cabbage
Phosphorus
Potassium
Fertilizer effect
