酸沉降对蔬菜吸收养分的影响

重庆市是我国受酸沉降影响较严重的地区之一，采用田间试验方法研究了酸沉降对蔬菜(豇豆、甘蓝和西红柿)吸收养分的影响。对酸沉降影响的机理进行了简要的分析和讨论。在污染区和对照区吸收养分的影响的试验困块中种植试验结果表明，由于试验田块中酸沉降的输入不同和土壤酸化程度的不同，蔬菜吸收N、P、K和S营养元素受到的影响也不同。污染区降雨中s的输入是对照区的2倍。污染区单位面积蔬菜对N、P、K和S的吸收均低于对照区，尤以K吸收的减少最为明显。3种蔬菜受酸沉降影响的程度也不同，西红柿和豇豆对酸沉降和土壤酸化比较敏感，甘蓝具有一定的抗性。

Effects of Acid Deposition on Uptake of Nutrients by Vegetables

Chongqing City is one of the regions seriously affected by acid deposition in China. In order to study effects of acid depositions on nutrients absorption of vegetables, several plots, where cowpea, cabbage and tomato were grown, were carried out with polluted and control areas in Chongqing. The experimental results showed that effects on vegetable absorption of N, P, K and S were different based on various inputs of acid depositions and different soil acidification. We found that the input of S in the heavily polluted area was as high as double in control area. For individual vegetable, the amounts of K, P, N and S adsorbed by the vegetable at the heavily polluted plot were generally lower than that at control area. The reduction of K absorption was the most significant in comparison with other tested elements. There was also obvious difference between three vegetables. Tomato and cowpea both have been found to be sensitive to acidic deposition and acidified soil, but cabbage is rather resistant. Mechanism of acid deposition effects on plant nutrients was briefly analyzed and discussed in the present study.