Response Mechanism Of Soil Organic Carbon To Different Agricultural Tillage Methods In The North Of Yinshan

The north of Yinshan is exposed to the soil under the traditional plowing,and the soil erosion is serious,which reduces the soil carbon pool and threatens the atmospheric changes and the local food security.In this article,the changes of organic carbon and activated organic carbon in soils under different fertilization and conservation tillage practices(no tillage with straw cover and tillage)were studied in this paper,exploring the relationship between soil organic carbon and soil enzyme activities,soil nutrient,screening for local farming practices.The results showed that:(1)The content of organic carbon and the content of active organic carbon in soils were improved by different fertilization treatments.Among that,the treatment of NPK was better,and the indexes were increased by 15.75%,27.24%,28.05%and 2.71%respectively.The contents of SOC,MBC,DOC and ROC of straw whole-coverage were higher than those of other treatments,followed by straw half-coverage and traditional tillage.The SOC and active organic carbon contents of deep loose in different tillage treatments were higher,and increased by 41.56%,20.34%,1.50%and 5.22%respectively.(2)The percent of soil active organic carbon in soil organic carbon under different farming measures was different.Under the fertilization treatment,the percent of ROC/SOC was lower than that of contrast,while the value of DOC/SOC and MBC/SOC was higher than control.Under the condition of no-till stubble,the ROC/SOC of GCW was lower than that of traditional tillage,the value of SOC/SOC,MBC/SOC were not significantly different from conventional tillage values.The ROC/SOC,DOC/SOC and MBC/SOC values were significantly lower than those of conventional tillage under different tillage.(3)Different agricultural measures can improve soil enzyme activity.The activities of soil sucrase,catalase and alkaline phosphatase were significantly higher than those of non-fertilization under NPK.The activities of urease were better with NP.Under the condition of no-tillage stubble treatment,the effect of stay stubble full coverage on soil enzyme activity was not significant.but stay stubble full coverage treatment was better.The different tillage treatment significantly increased the activity of sucrase in soil,but had no significant effect on catalase,urease and alkaline phosphatase,and the performance of deep loose was better.(4)Different agricultural methods have improved the soil nutrient.Under the fertilization treatments,NP and NPK significantly increased the content of soil organic matter.And the content of available nitrogen was significantly increased on the nitrogen fertilizer,but the effect of total nitrogen was not significant.The content of available phosphorus and total phosphorus was significantly increased by single application of phosphate fertilizer.The content of available potassium and total potassium in the soil treated with potassium fertilizer was the highest.Under the condition of no-till stubble,the content of straw was significantly higher than that of traditional tillage,but the difference of straw mulching and stubble was not significant.The contents of available nitrogen,available phosphorus,available potassium,total nitrogen and total potassium were significantly increased by no-tillage straw mulching,while the effect of different tillage treatments could significantly increase soil organic matter,available phosphorus and available potassium,and the effect of SS treatment on total nitrogen,total phosphorus and total potassium was significant.(5)Different farming measures can improve crop yields,which performed better measures were NPK,deep loose and stay stubble with full coverage,and compared with the control increased 45.16%?75.32%?56.89%respectively,and there was significant difference with other treatments.(6)Analysis of correlation between soil organic carbon and active organic carbon components that there was a significant positive correlation between SOC and ROC,DOC,MBC in 3 agricultural methods.The correlation analysis of soil enzyme activity and SOC showed that there was a significant positive correlation between SOC and catalase,sucrase,urease and alkaline phosphatase activity under fertilization and no-tillage.And soil organic carbon and catalase activities were not related,but there was correlation between SOC and sucrase,urease and alkaline phosphatase.Correlation analysis of soil organic carbon with soil nutrient showed that soil organic carbon and soil available nitrogen,available potassium,total nitrogen and total potassium were significant,but not with available phosphorus and total phosphorus.And there was a significant correlation between soil organic carbon and total nutrient and available nutrient in soil under conservation tillage.(7)The results showed that the contribution rate of the main components under the three kinds of agricultural measures was 100%,99.9999%and 99.9999%respectively,and the impact of soil indicators are the first three main components.The contribution rate of the main component and the conservation tillage measures is higher than that of the fertilization treatment.In conclusion,the analysis of soil organic carbon composition,enzyme activity and soil nutrient found that the three measures can increase the content of each soil index,but the correlation analysis between the indicators and principal component analysis shows that conservation tillage measures are more conducive to soil continuous development,and the best measures are zero tillage with total mulching and deep loose with Straw back to field.