| Field experiment was used in this experiment.In the first part,5a soil was reclaimed from luojianggou village,wangqiao town,xiangyuan county,changzhi city,Shanxi Province.Organic fertilizer,inorganic fertilizer and biochar were applied in combination.The second part takes the 3a soil reclaimed from xshandi village of xiangyuan county as the research object,applying organic fertilizer,inorganic fertilizer and nitrogen-fixing bacteria fertilizer.The effects of organic and inorganic fertilizer combined with biochar fertilizer on soil nitrogen and maize yield in coal mining and reclamation were studied to provide theoretical basis for exploring the effect and mechanism of biochar and nitrogen-fixing bacteria on soil nitrogen in reclamation.The test results are as follows:(1)Compared with the control group,the contents of alkali-hydrolyzed nitrogen,nitrate nitrogen and microbial nitrogen in the reclaimed soil were all increased by the combined application of biochar,and the improvement effect of organic fertilizer + biochar treatment was the most significant.(2)Compared with the control group,the contents of total nitrogen,total acidolysis nitrogen and non-acidolysis nitrogen in the reclaimed soil were significantly increased by biochar.Compared with the same fertilization treatment without biochar,total nitrogen increased by 0.64%~1.47%.Total acidolysis nitrogen increased by 2.15%~3.11%.Non-acidolysis nitrogen was reduced by 2.89%~5.05%.There was no significant difference in total nitrogen content of reclaimed soil between inorganic fertilizer + biochar,organic fertilizer + biochar,organic fertilizer + inorganic fertilizer + biochar.The organic fertilizer and biochar treatment had the most significant effect on improving the total nitrogen content of acidolysis in reclaimed soil.The content of non-acidolysis nitrogen was significantly reduced by organic fertilizer and biochar treatment.(3)Compared with the control group,the contents of amino acid nitrogen,amino sugar nitrogen and unknown acidolysis nitrogen in the acidolysis nitrogen components of reclaimed soil were increased with biochar,and the contents of ammonia nitrogen were decreased.The contents of amino acid nitrogen and acidolysis unknown nitrogen in organic fertilizer + biochar treatment were the highest,which increased by7.74%(P<0.05)and 3.65%(P<0.05),respectively,compared with the single organic fertilizer treatment.The content of amino sugar nitrogen in inorganic fertilizer + organic fertilizer + biochar was the highest,which was 16.34% higher than that in inorganic fertilizer + organic fertilizer(P<0.05).Biochar can increase the yield of corn in reclaimed soil.Among them,the corn yield under organic fertilizer + biochar treatment was the highest,with an increase of 4.25% compared with that under organic fertilizer treatment(P<0.05).(4)In the seedling stage,the elongation stage and the maturity stage of maize,compared with the control group,the addition of nitrogen fixation fertilizer had a significant effect on the improvement of urease,protease,glutaminase and asparaginase in reclaimed soil(P<0.05).The activities of urease,protease,glutaminase and asparaginase were the highest under the treatment of organic fertilizer + nitrogen-fixing bacteria,which were 17.91%~25.59%,18.58%~33.26%,21.36%~31.40%,27.37%~37.51% higher than those under the treatment of organic fertilizer.(5)In the seedling stage,jointing stage and maturity stage of maize,compared with the control group,the contents of nitrate nitrogen and ammonium nitrogen in reclaimed soil were significantly increased by adding nitrogen-fixing bacteria fertilizer(P<0.05).The content of nitrate nitrogen and ammonium nitrogen in organic fertilizer + nitrogen-fixing bacteria fertilizer treatment was the highest,which were 12.70%~19.29% and 20.32%~27.84% higher than that in organic fertilizer treatment.It can be seen from the three growing stages of maize that the improvement effect of nitrogen-fixing bacterial fertilizer treatment is significant(P<0.05),which is shown as the > jointing stage of > seedling stage in the maturity stage.The microbial nitrogen content of organic fertilizer + nitrogen-fixing bacteria fertilizer treatment was the highest,13.55%~17.80% higher than that of organic fertilizer treatment.(6)In the seedling stage,jointing stage and maturity stage of maize,compared with the control group,the contents of total nitrogen acidolysis and non-acidolysis nitrogen in reclaimed soil were significantly increased by applying nitrogen-fixing bacteria fertilizer(P<0.05).Among them,organic fertilizer + nitrogen-fixing bacteria fertilizer and organic fertilizer + inorganic fertilizer + nitrogen-fixing bacteria fertilizer significantly increased the total nitrogen and non-acidolysis nitrogen content of reclaimed soil in three periods,but the difference was not significant.The organic fertilizer +nitrogen-fixing bacteria fertilizer treatment had the best effect on the improvement of total acidolysis nitrogen in reclaimed soil.(7)In the seedling stage,jointing stage and maturity stage of maize,compared with the control group,the addition of nitrogen-fixing bacteria fertilizer can increase the contents of ammonia nitrogen,amino acid nitrogen and amino sugar nitrogen in reclaimed soil.Among them,the organic fertilizer +nitrogen-fixing bacteria fertilizer treatment had the best effect on the improvement of ammonia nitrogen,amino acid nitrogen and amino sugar nitrogen in reclaimed soil.However,only in the mature stage of maize,the addition of nitrogen-fixing bacteria fertilizer can increase the content of unknown nitrogen in acidolysis.Compared with the control group,the yield of maize under all fertilization treatments was significantly increased by 82.31%~130.77%.Under the same fertilization treatment,increasing application of nitrogen fixation fertilizer can increase the yield of corn in reclaimed soil,but the effect is not significant.To sum up,the combined application of biochar and nitrogen-fixing bacteria fertilizer can increase the content of total nitrogen and organic nitrogen components in reclaimed soil and the yield of corn,among which the organic fertilizer + biochar,organic fertilizer + nitrogen-fixing bacteria fertilizer has the best improvement effect,which has a great help to enhance the nitrogen supply level of reclaimed soil and improve soil fertility. |
PDF Full Text Request