Preliminary Study On Cd Absorption And Movement Of Peach In Soil

With the development and progress of human society,industrial production has become an inseparable part of human society.With the development of industry,serious pollution has been brought to the environment,among which soil heavy metal pollution has become an urgent problem to be solved.In recent years,Hunan has become a heavy metal cadmium pollution disaster area.In this experiment,a large number of samples were taken from peach orchard in Hunan province,and the heavy metal content in the soil and fruit was detected and analyzed.To understand the current situation of cadmium pollution in peaches in Hunan province.Meanwhile,pot experiment was conducted to further analyze the distribution and transport of cadmium in peach trees and soil under different concentrations of cadmium stress.The main research results are as follows:1.Cadmium content in peach orchard soil in different regions of Hunan province was detected and counted.Cadmium content in peach orchard soil was 1.61 at the highest level and 0.09 at the lowest.The p H range was 4.60-8.02,where the minimum p H value was 4.60 and the maximum p H value was 8.02.The p H of 40 soil samples ranged from 4.60 to 7.0,indicating that most peach orchard in Hunan was dominated by acidic soil.The overall level of cadmium in the soil is represented by the arithmetic mean and coefficient of variation.In the statistics,the average VALUE of Cd is 0.35,which is much higher than the background value of China and the world,indicating that peach orchard in Hunan is polluted by cadmium.The coefficient of variation of Cd was 95.74%,which was large,indicating that the content of cadmium in the soil in Hunan was unevenly distributed and there were regional differences.2.A total of 232 plant samples were collected in Hunan.58 fruit samples were taken.Cadmium content in 21 fruit samples exceeded the national standard value of 0.03.The cadmium content of each organ in the plant was distributed in the stem > root > leaf > fruit.The accumulation of cadmium in stem is much larger than that in fruit.Cadmium accumulation ability of peach fruits of different varieties is different.3.In the pot experiment,different cadmium concentrations were used to accumulate cadmium in different parts of the plant,and the higher the cadmium concentration was,the more the accumulation was in each part,and the difference was the most obvious among the roots.The enrichment ability was strongest under 9mg/kg cadmium stress and weakest under0mg/kg cadmium stress.Under the stress of 9mg/kg Cd,the enrichment coefficient of root was 0.1283.Under the stress of 0mg/kg Cd,the enrichment coefficient of root was 1.038.The enrichment coefficient of various parts of plants under cadmium stress decreased with the increase of cadmium stress,and the transport coefficient also decreased with the increase of cadmium stress.4.Cadmium content in peach leaves decreases during the vigorous growth period and during the deciduous period.This is due to the fact that in order to satisfy the growth of new branches and leaves during the growth period,the central division of the old leaves is transferred to the part with vigorous growth.In order to store energy during the deciduous period,plants transfer nutrients from leaves to roots and other places for storage before the leaves fall,which are used to resist the cold winter and for growth in the following year.In the process of nutrient transfer,cadmium,a heavy metal in the leaves,is also transported to the rhizome,leading to a relatively low cadmium content in the leaves.