Effect Of Nutrient Elements On Cadmium Accumulation Of Bermuda Grass(Cynodon Dactylon(L.)Pers.)

The hotspots of phytoremediation are focus on screening of hyperaccumulator plants,enhancing heavy metal enrichment of plant by seeking relevant functional genes,improving the extraction rate of heavy metal Cd by soil additives,etc recently.However,there have been no studies demonstrating the correlation between nutrient element exchange in the vegetation-soil ecosystem,the nutrient element distribution in plants and the Cd accumulation capacity of plants.In the research,nine group of soil with different Cd pollution level and different nutrient level were selected as sources of the pot experiment,the water with different degree of stress of Cd were selected as the sources of the hydroponic experiments and the KNO₃ and?NH₄?₃PO₄ were added to the hydroponic experiments under the same degree of Cd stress.The addition of KNO₃ and?NH₄?₃PO₄ can alter nutrient availability in nutrient solution.The research systematic study and verify the effect of nutrient factors on accumulation capacity of Cd.The research provides a theoretical basis for improving the ability of Cd accumulation of plants by improving soil environmental factors.?1?The Cd content of the fifth group(36.11 mg kg^-1)was close to the eighth group(35.72mg kg^-1),but the fifth groups compared to the eighth group was significant rise of plant height,NH₄⁺-N,available phosphorus,the Cd bioconcentration factors?BCF?and translocation factor?TCF?.RDA analysis indicated the BCF were positively correlated with soil NH₄⁺-N,available potassium and available phosphorus and negatively correlated with soil NO₃^--N.The TCF were positively correlated with soil NH₄⁺-N and available phosphorus.?2?With the increase of Cd concentration,the treatment compared to the CK treatment were significant increase of N,P K and Cd content in root,stem,and leaf?the N in the stem and the P in the leaf are not included?.The accumulation of N,P and K in the root,stem and leaf showed a decreasing trend,while the accumulation of Cd showed no significant difference.Pearson analysis indicated that the stem content of N,P and K was significant positively correlated with stem content of Cd,the root,stem and leaf content of N,P,K was significant positively correlated with leaf content of Cd.?3?Under the stress of the same Cd concentration,the addition of KNO₃ and?NH₄?₃PO₄ can significantly improve the BCF.Meanwhile,the treatment compared to the CD treatment were significant increase of biomass and the N,P,K accumulation content in stem and root and were not significant of pH and available Cd content in nutrient solution.Plants increased Cd accumulation by increasing biomass and assigning higher N,P,K accumulation content to stem and root at add the KNO₃ and?NH₄?₃PO₄.The result indicated that increase soil nutrient availability could improve the ability of accumulation Cd in the Bermudagrass.