Effects of humic acid modified copper contaminated soil on wheat growth and nutrient uptake
In order to evaluate the improvement effect of humic acid on copper contaminated soil,the two-factor winter wheat pot experiment of copper and humic acid in the field were set up to study the accumulation and distribution of dry matter and the absorption and utilization of nitrogen,phosphorus and copper elements in winter wheat.The main results were as follows:(1)The copper contaminated soil(CS)restrained the growth of wheat organs and significantly reduced the total biomass by 28.7％-66.9％,and reduced nitrogen and phosphorus uptake by 18.4％-61.5％and 9.6％-65.5％,respectively,and nitrogen and phosphorus harvest index decreased significantly.However,the CS significantly increased copper uptake by 40.5％-115.2％,while dropped the migration coefficient of stem to leaf and wheatear,which made no change in the harvest index.(2)Application of humic acid obviously improved the inhibitory growth of root,stem and wheatear and alleviated the adverse effects of absorption of nitrogen and phosphorus reduction on wheat due to soil copper pollution.Compared with copper pollution treatment,low(20 g/kg dry soil)and high(40 g/kg dry soil)dosage of humic acid significantly increased the biomass by 25.0％and 115.6％,respectively,and promoted the absorption of nitrogen(22.6％-111.9％)and phosphorus(28.3％-161.9％)and harvest index of nitrogen and phosphorus.The application of large dosage of humic acid was more help for wheat resistance to copper pollution hazard stresses.(3)The application of humic acid significantly increased the accumulation of copper by a significant increase in copper migration coefficient from stem to leaf(12.2％-30.7％)and from stem to wheatear(46.8％-71.9％),although it could significantly reduce the copper harvest index of wheat by 7.2％to 9.0％.Unfortunately,this led to an increased accumulation of copper in the spike.Obviously,the agricultural effect of humic acid ameliorant copper contaminated soil requires further analysis.
万方数据
维普
