Effect of Mixed Rare Earth Elements on the Growth and Photosynthesis of Eichhornia crassipes

摘要

The growth and photosynthesis of Eichhornia crassipes affected by mixed rare earth elements (REEs) were measured under indoor mesocosm. The results showed that appropriate concentration range of mixed REEs could promote Eichhornia crassipes absorbing nitrogen and phosphorus effectively, and improve the efficiency of light energy utilization and transformation which made photosynthesis improved, and thus it could promote plant growth, and improve contents of protein and chlorophyll;;fatherly, with increase of Eichhornia crassipes breeding density, dissolved oxygen (DO) reduced but chemical oxygen demand (COD) raised (a maximum value of 16.170 mg/L) in water, which eventually led to water quality worsen. The research results demonstrate that suitable contents of mixed REEs can promote aquatic plants such as Eichhornia crassipes growing, thereby contributing a positive catalytic effect to the development process of eutrophication.