Study on the Cadmium Accumulation Effect of Passivation Treatment on Water Spinach Under Two Planting Modes of Water and Drought Planting Modes
[Objective]In order to reduce the risk of heavy metal pollution in soil and ensure the safety of crop production,field planting exper-iments of water spinach were conducted to study the passivation effect of different types of soil passivators on cadmium under two planting modes of water and drought.[Method]By setting two different planting modes,such as flooded planting and dry planting,the changes of soil pH,nutrient content,availability of heavy metal cadmium,yield of water spinach and concentration of heavy metal cadmium were compared un-der the application of four soil passivators,such as lime,sepiolite,modified molybdenum silicate and biochar.[Result]Under the dry planting,the cadmium content of water spinach in each treatment was 0.11-0.13 mg/kg,with a decrease of 13.42%-23.74%,the reduction effect was ranked as:sepiolite＞lime＞biochar＞modified molybdenum silicate.Under the flooded planting,the cadmium content of water spinach in each treatment was 0.08-0.11 mg/kg,with a decrease of 4.54%-18.22%,the reduction effect was ranked as modified molybdenum silicate＞lime＞biochar＞sepiolite.Four passivators could effectively passivate cadmium in soil,reducing the available cadmium in soil by 5.88%to 35.00%and decreasing the cadmium content in water spinach by 4.54%to 27.72%.Under the same passivators conditions,submerged planting could ef-fectively reduce the cadmium content in water spinach by 3.91%to 33.34%,with modified molybdenum silicate showing the best effect and a reduction of 33.34%.At the same time,modified molybdenum silicate had the effect of increasing yield under water and drought planting modes,while sepiolite and biochar could cause yield reduction.[Conclusion]"Flooding planting+modified molybdenum silicate"is a safe utili-zation technology system for heavy metal cadmium in vegetable farmland.
万方数据
维普
