| Heavy metal contaminant is the key research field in soil and environment science. With the development of industrialization, urbanization, agriculture and aquaculture, heavy metal contamination in the soil becomes increasingly serious. About 2.0 107 ha of plowland was contaminated by heavy metal in China. The pollution of soil caused by Cd attracts more and more attention of scientists. But According to the reality of huge stress of food caused by large population and decreasing farmland, it is not feasible to stop to remediate contaminated soil and reuse. Targeted remediation can be put in practice merely in some areas. Thus, it's necessary to seek effective approach to control pollution of agricultural products which contaminated by heavy metals in soil, and insure safe and efficient performance of contaminated soil.In this experiment, the glasshouse pot experiment was used to study the influence of two degrees Cd to 28 usual vegetables'growth, and differences of absorption and accumulation of cadmium. Meanwhile, different accumulation abilities of 5 vegetable varieties of Cd were researched. The purpose of the research was to screen out low accumulators, provide theoretical support to model of safety production and sustainable development. This experimental goal was providing scientific basis for the non-environmental pollution vegetables production and the pollution soil improvement as well as the non-environmental pollution vegetables base development plan. The potted experiment results show that:(1) During research of the influence of Cd to vegetables'growth, we found there is no significant difference between the same vegetable through potted experiment when grown in contaminated soil by 1 mg kg-1and 2 mg kg-1 Cd. No obvious injured symptom was observed.(2) Through the experiment of screening uncontaminated food standard, we could concluded that except sweet pea under 2 concentrations exposures and bitter melon under 1 mg kg-1 exposure, the concentrations of Cd in vegetables'body all went beyond the limit of uncontaminated food standard. Huabijiadouwang under 2 concentrations exposures, chaojisijidou, dabaikugua, changlvkugua, teyuchangbaikukua, zhongdusihao under 1 mg kg-1 exposure all conformed to the uncontaminated food standard.(3) According to the experiment of differences of absorption abilities of Cd by vegetables, it could be concluded that different vegetables had different accumulation abilities for Cd. Leafy vegetables and solanaceous vegetables had the strongest ability of uptake Cd from soil. The abilities of uptake Cd were weakening followed the order: root vegetables, scallions, gourds, legumes. With the increase of Cd concentrations in soil, the concentration in vegetables showed an increasing trend as a whole, but not proportionable. Absorption abilities of most vegetables slowed down with the increase of Cd concentrations in soil. Under 1 mg kg-1 Cd exposure, concentrations of Cd in legume was in a range of 0.0266～0.0782 mg kg-1, bitter melon 0.0271～0.0513 mg kg-1, vigna unguiculata 0.0500～0.0882 mg kg-1, summer squash 0.0958～0.158 mg kg-1, cucumber 0.101～0.173 mg/kg. Under 2 mg kg-1 Cd exposure, concentrations of Cd in legume was in a range of 0.0488～0.0990 mg kg-1, bitter melon 0.0847～0.146 mg kg-1, vigna unguiculata 0.108～0.143 mg kg-1, summer squash 0.163～0.253 mg kg-1, cucumber 0.118～0.205 mg kg-1.(4) According to the experiment of differences of absorption abilities of Cd by vegetable varieties, between 23 vegetables varieties, legume and bitter melon were lower accumulators, while accumulation abilities of cucumber and summer squash were much higher. Under 2 degrees of Cd exposure, the concentrations among legume varieties had 2～3 times difference, bitter melon 2 times, vigna unguiculata 1 time, cucumber 1.7 times, summer squash 1.6. The enriching factors among different vegetable varieties had obvious difference. With the increase of Cd concentration in soil, the enriching factors reduced. |
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