Absorption And Accumulation Characteristics And Physioligical Response Characteristics Of Non-heading Chinese Cabbages To Lead And Zinc

Vegetables pollution of zinc and lead is a serious problem reducing quality of vegetable product and harming human health. Pot experiment was conducted to study the influences of lead and zinc single and compound pollution on the growth of non-heading Chinese cabbage in cinnamon soil. Meanwhile, the absorbing and accumulating characters of zinc and lead in non-heading Chinese cabbage were studied. The physiological responses to the toxicity of zinc and lead in the non-heading Chinese cabbage were analyzed. The main results are as follows:1. All growing stages soil culture experiment of non-heading Chinese cabbage showed that, under the condition of zinc and lead single pollution, zinc and lead concentrations in non-heading Chinese cabbage were significantly linearly correlated to the added zinc and lead leaves in the soil. Under the condition of zinc and lead compound pollution, zinc and lead concentrations in non-heading Chinese cabbage were not only mainly influenced by the added zinc and lead levels respectively, but also influenced by co-existent heavy metal element.2. The concentration order of lead in different parts of non-heading Chinese cabbage was: under the condition of lead and zinc single and compound pollution, the distribution of lead indifferent parts of non-heading Chinese cabbage was:root> stem and leaf. The distribution of zinc indifferent parts of non-heading Chinese cabbage was:stem and leaf>root.3. Under single pollution, the thresholds of zinc and lead in the tested soil for non-heading Chinese cabbage were 218.05mg/kg,29.08mg/kg. These thresholds could become a basis of evaluating the quality of vegetable polluted by the heavy metals.4. Under the condition of zinc and lead single and compound pollution, the aboveground biomass, underground biomass and root activity of non-heading Chinese cabbage first increased, then decreased as the increased of zinc and lead concentration. Chlorophyll contents of non-heading Chinese cabbage changed complicatedly as the increase of concentration, but the chlorophyll contents of non-heading Chinese cabbage were all lower than the chlorophyll content of non-heading Chinese cabbage under the condition of standard sample.