Effects Of Application Of Iron Ore Tailing Sands In Soil On Physiological Property Of Gardenia Jasminoides Ellis

With the rapid development of national economy,a large number of mineral resources are explored and utilized,the emissions of ore tailing has increased year by year,and the problem of ore tailing accumulation have become more and more serious.Many ways for the comprehensive utilization of ore tailing method has become a hot spot of current research.Through the improvement of covering soil from Jinshandian iron ore tailings dam slope,to explore the feasibility of iron ore tailing sands used in mine land reclamation and vegetation restoration.Research team conducted a pot experiment study of mixing different proportion of iron tailing sands with soil to plant gardenia,in which,the enzymatic activity,resistant index,chlorophyll content and the contents and uptakes of nutrient in gardenia was determined,the influence of different sand proportion on the gardenia physiological property were studied.The purpose is to provide basic data for iron ore tailing sands utilization.(1)The mixing tailing sands with soil had significant effect on the enzymatic activity of gardenia.Low proportion of tailing sands can promote the enzymatic activity of gardenia.The activities of catalase(CAT),peroxidase(POD)and polyphenol oxidase(PPO)reached the maximum between 20%-50%by mixing tailing sands with soil.When the mixing rate was over 60%,the activities of CAT and POD was suppressed,which were significantly lower than control,but the activity of PPO was not suppressed by tailing sands.(2)The tailing sands had been less affected by the resistant index of gardenia.The low mixing rate did not produce obvious effect on the content of malondialdehyde(MDA)and proline(Pro).Since the mixing rate reached 60%,the content of MDA and Pro were increased,that the intimidated degree of gardenia were rising.The content of VC did not show obvious rule with the increase of sand proportion,but it was significantly lower than control in mixed sand of 90%.(3)The tailing sands had an effect on gardenia's chlorophyll.The content of chlorophyll a was significantly higher than the content of chlorophyll b and c.With the increase of the mixed sand ratio,the content of chlorophyll a,b,c and a+b reached the maximum in the mixing rate of 30%,and reached the minimum in the mixing rate of 60%,The ratio of Chlorophyll a/b was less affected by the sailing sands.(4)The results showed that mixing iron ore tailing with soil had a significant effect on the nutrient contents and the allocation of nutrient uptake in each part of gardenia.Nitrogen,phosphorus,potassium and magnesium were the stronger elements of mobility and reuse than Iron and calcium in gardenia.The order of nitrogen content in gardenia was green leaf>root>stem>yellow leaf.When the mixing rate was 10%-40%,the nitrogen uptake of gardenia in aerial parts was significantly higher than the control,among which 30%mixing rate was the highest.The order of phosphorus content in gardenia was green leaf>yellow leaf,root>stem.It beneficial to improve phosphorus uptake of gardenia in aerial parts When the mixing rate was 10%?60%,among which 30%and 60%mixing rate were the highest.The order of potassium content in gardenia was green leaf>yellow leaf>root>stem.It beneficial to improve potassium uptake of gardenia in aerial parts When the mixing rate was 10%-50%,among which 30%mixing rate were the highest.The order of iron and calcium content in gardenia were stem>yellow leaf>root>stem and yellow leaf>green leaf>root and stem.When the mixing rate was 20%?70%,the iron and calcium uptake of gardenia in aerial parts were improved,among which 30%and 20%mixing rate was the highest.The order of magnesium content in gardenia was green leaf>yellow leaf>root>stem.The tailing sands had not significant effect on the magnesium uptake of gardenia in aerial parts.In summary,some application rates of iron ore tailing in soil can accelerate the growth of gardenia by translocation of soil nutrients to aerial and tender parts.(5)According to the enzymatic activity,resistant index,chlorophyll content and the nutrient contents and the allocation of nutrient uptakes in gardenia,the suitable application rate of iron ore tailing in soil ranges from 20%to 50%and the most suitable rate is around 30%.