山东省蔬菜大棚养分积累状况

利用养分投入产出平衡分析方法,根据山东省大棚蔬菜施肥农户抽样调查结果,分析研究了大棚蔬菜养分积累状况及其形成原因.结果表明,大棚蔬菜生产中,几种主要蔬菜如黄瓜、番茄、辣椒、西葫芦等均会造成NPK养分在土壤中的大量累积,其中以P最为突出,黄瓜每季P2O5累积量在4000kg/hm2以上,N和K2O也在1500kg/hm2以上,由此带来巨大的环境风险;投入量大大超过吸收量是最主要原因,NP比例失调,P的比例过高使得P累积最为突出;以磷酸二铵和等养分三元复合肥为主的肥料品种结构也是P高量累积的重要原因.

Nutrients accumulation within vegetable awning (green house) in Shandong province

Sampling investigation of the crop fertilization by farmers in Shandong province in 1997 was conducted. Base on the investigative data, the situation and reason of nutrient accumulation in vegetable awning(green house) in Shandong province were studied. As planting cucumber, tomato, chilli and squash, the large amount of nutrients would be accumulated in soils. The P accumulation was the most significant, and the accumulative amount of P_2O_5 in cucumber field was above 4 000 kg/hm2 and that of N or K_2O was also above 1 500 kg/hm2 in one season. The main reason of nutrient accumulation was that the input was many more than uptake amount. Inappropriate NPK ratio, which was caused by the application of DAP and NPK fertilizers (151515 or 161616), resulted in P large accumulation.