上海地产绿叶菜种植土壤养分评价及改良建议

Evaluation of soil nutrients and countermeasure of soil improvement in Shanghai local leaf vegetables

通过调查上海市绿叶菜茬口的化肥投入和土壤地力情况,对其土壤有机质含量、盐分含量、pH及速效氮、磷、钾含量进行分级和评价。结果表明:叶菜茬口年化肥投入量(N+P_(2)O_(5)+K_(2)O)达到1180.5—1206.0 kg∕hm^(2),土壤正在发生酸化和次生盐渍化。pH小于6.5的土壤占58.6%,盐分含量超过2 g∕kg的土壤占77.1%,有机质含量大于35 g∕kg的土壤占6.7%。不合理施肥造成土壤中氮磷钾养分过量现象极为普遍,土壤碱解氮、有效磷和速效钾平均含量分别为163.5 mg∕kg、136.3 mg∕kg和313.6 mg∕kg。综上,上海都市农业绿色发展背景下应大力推广因土因作物专用肥精准施肥技术、土壤培肥技术和水肥一体化技术等减施增效措施,以更好地维持设施土壤的可持续利用。

Based on the investigation of chemical fertilizer input and soil fertility of green leaf vegetables,soil pH,organic matter,available nitrogen,phosphorus,potassium and other nutrients content were determined by collecting soil samples,and soil fertility was graded and evaluated by according the detected data.The results showed that the annual chemical fertilizer input(N+P_(2)O_(5)+K_(2)O)of leaf vegetables were 1180.5-1206.0 kg∕hm^(2),the problems of soil acidification and secondary salinization at surface soil were remarkable of greenhouses.There was 58.6%soil with the pH less than 6.5,and 77.1%soil with salt content over 2 g∕kg.The soil organic matter was not rich,where the content over 35 g∕kg took up 6.7%.With inappropriate applications of nutrients,unusual accumulations of N,P,K appeared commonly in the soils under greenhouse.The averaged content of soil available N,P_(2)O_(5) and K_(2)O was 163.5 mg∕kg,136.3 mg∕kg and 313.6 mg∕kg.In view of this,soil testing and fertilizer recommendation,soil organic fertilization technology,water-soluble fertilizer and fertigation should be greatly promoted under agriculture green development.