| Application of fungus chaff is an important measure improving soil healthy,plant growth,microbial activity and heavy metal effects.In order to solve the fungus chaff on environmental pollution and its effective use to provide a scientific basis.A field experiment was conducted to investigate the effects of fungus chaff incorporation on plant height,stem diameter,yield and total biomass.soil microorganism,soil microbial biomass carbon,soil microbial biomass nitrogen and enzyme activity in three crops(maize,sorghum and waxy maize)soil at different growth stages.1)The application of the fungus chaff to promote the growth of three crops and the growth of stem and stem,plant height and stem diameter showed increasing trend.The plant height of the three crops of sorghum,maize and waxy maize increased by 8.57%,5.56%and 1.01%respectively compared with those without applying fungus chaff.The difference of stem diameter of sorghum was significant,which was 16.52%higher.The yield of sorghum and waxy maize showed a trend of increasing grain yield and aboveground biomass of three crops.The yield of maize and the total biomass of aboveground area decreased slightly,the reduction rates were 1.6%and 4.59%.2)The application of fungus chaff to promote the absorption of nitrogen,phosphorus and potassium in three kinds of crops.The three kinds of crops kernels were the highest ranging from 4.31 to 6.97 mg·kg-1.There was no significant difference in nitrogen content,and the increase rate of maize grain was 8.41%.The growth rate of maize and sorghum was 1.60%and 8.66%3)The incorporation of fungus chaff significantly increased bacteria and actinomyces population in the rhizosphere soil layer.The number of soil bacteria increased by 32%-54%for the three crops after fungus chaff application throughout the growth period.At maturity,actinomyces population significantly increased,especially in maize rhizosphere soil layer where there was the largest increment of 101%.The trend in fungi population increased at jointing and heading stages after decreasing at maturity stage.4)The use of fungus chaff in rhizosphere soil increased the activities of enzymes(urease,catalase and invertase).Soil urease activity under sorghum,corn and waxy corn increased with 239%,189%,and 184%,respectively.Soil catalase activity was highest at heading stage,with a maximum increment of 40%.Three crops showed different trends in soil invertase activity at each stage.The activity of soil invertase under maize was not significantly different among growth stages,with increment of 38%,28%and 48%respectively at jointing,heading and mature stages.5)Soil microbial biomass carbon and nitrogen increased in all the crops after fungus chaff application.The increase in soil microbial carbon content was 58.10-407.67 mg·kg-1 and that in microbial nitrogen content was 11.98-27.55 mg·kg-1 across the growth periods of the three crops.6)The addition of fungus chaff to reduce the total amount of copper and chromium in the soil of the sewage irrigation area.The reduction rate of Cu was in the range of 3.17%-16.2%,and the reduction rate of Cu was between 5%and 15.35%.The reduction rate of Cu in the soil was 6.17%-18.57%Within the range,Cr content reduction rate of 8.94%-20.58%.7)Application of fungus chaff to improve the carbonated-bound forms,organic-bound forms,residual forms copper chromium reduction rate range.In addition to the exchangeable copper content showed an increasing trend,the other forms of copper and chromium showed a decreasing trend.Among the three crops,the change rate of copper and chromium in maize soil was significantly higher than that of the other two crops,which was consistent with the reduction rate of copper and chromium in soil.In the soil of the applied fungus chaff,the reduction rate of copper and chromium in the other three soils was higher than that of the iron and manganese oxides forms in the corn soil,Indicating that in addition to carbonate-bonded copper content,the application of fungus chaff irrigation area can promote the various forms of copper,chromium content reduction.So the bacteria bran can promote the heavy metal copper chromium carbonated-bound forms,organic-bound forms,the residual forms of the fixed.8)The fungus chaff reduced the enrichment of Cu and Cr in the upper part of the three crops,and the root enrichment ability of Cu and Cr was higher than that of stem,leaf and grain for the three crops.Besides,the enrichment ability of Cu and Cr in maize,sorghum and waxy maize with fungus chaff was lower than that of non-applied fungus chaff.After the application of fungus chaff,most of Cu and Cr was fixed in the underground,which played a role in inhibiting plant absorption.9)The fungus chaff reduced the content of copper and chrome in grains of maize and waxy maize.According to Chinese food hygienic standard,the content of copper in maize and waxy maize grains was not exceeded,and the content of chromium also reached the standard,which can be used as edible crops.However,Sorghum grain chromium content exceeded the national food hygienic standard but not more than the national feed hygienic standard,can be recommended as feed or industrial raw materials.It was therefore recommended to apply fungus chaff of to protect and improve future environmental conditions. |
