| Soil organic carbon（SOC）is an important index of soil fertility,the agronomic measures and human disturbance,the change of SOC library change and have a major impact on the climate environment,SOC components than the total SOC can better reflect the effects of agronomic measures on soil mechanism,is the key to evaluate agronomic measures effect factors.Soil desertification and drought are the key problems affecting the sustainable development of agriculture.Under different planting patterns,this article through to the bashang area of northwest Hebei SOC component and carbon management index（CPMI）change law research,further applying organic fertilizer content,agronomic measures such as management,plastic mulching fertilizer coupling simulation experiment was carried out,using SOC grading method,calculation of soil CPMI,retention of fat in bashang area of northwest Hebei,the sustainable development of the prevention and treatment of farmland soil degradation agronomic measures.The results are as follows:（1）Through the bashang area of northwest Hebei planting patterns of farmland SOC component analysis,to CPMI bashang grassland for residual control calculation results show that the bashang area of northwest Hebei farmland SOC content between 8.97～31.97 g?kg-1,the activity of soil organic carbon（ASOC）between 7.63～13.44 g?kg-1,increasing organic fertilizer or improve the field microclimate can improve soil and ASOC SOC content,reduce CPMI,increasing microorganism quantity and enzyme activity;The application of inorganic fertilizer can reduce the contents of SOC and ASOC,decrease the CPMI,decrease the microbial quantity and enzyme activity.Enough irrigation can improve SOC and ASOC content and reduce CPMI.Extensive management can reduce SOC and ASOC content,improve CPMI,and reduce microbial biomass carbon and enzyme activity.（2）The simulation test results of organic fertilizer dosage in greenhouse show that SOC content of different organic fertilizer dosage ranges from 9.67～41.97 g·kg-1,and CPMI ranges from 38.92～100.With an increase in the amount of organic fertilizer,low activity of organic carbon（L-LOM）to SOC ratio decreased,the content of active organic carbon（N-LOM）increased,ASOC content of each component are increasing trend,but the proportion of organic carbon,CPMI as an increase in the amount of organic fertilizer in the first fall after a rise trend,applying organic fertilizer content for 2 t·hm-2CPMI lowest,soil protecting fertilizer effect is best.（3）The results of indoor simulation test of carbon-water coupling show that ASOC content increases with the increase of organic carbon content and soil moisture content.In low carbon（soil organic carbon content is 0.5%）and carbon（soil organic carbon content of 4%）in the soil under the condition of SOC component L-LOM accounted for the highest,in high carbon（soil organic carbon content of 8%）under the condition of soil N-LOM SOC component proportion is highest,soil CPMI between 20.40～209.83,the water in the high carbon（50-60%of water holding capacity of the largest field）when CPMI minimum,under the condition of high carbon water in soil protecting fertilizer ability is higher.（4）Field simulation experiments with different film mulching witnesses showed that SOC content in different treatments ranged from 14.86 to 31.34g·kg-1,and soil CPMI ranged from 84.11 to 261.9,and film mulching could significantly increase SOC content.The order of SOC and ASOC contents is below>mulch next to>mulch above mulch.With the increase of the film width,CPMI decreases first and then increases.60（film width）:50（film width）CPMI covering method is the lowest,the fertilizer retention effect is better.From what has been discussed above:in order to solve the problems of soil degradation and carbon sink decline,organic fertilizer,inorganic fertilizer and proper irrigation should be applied.We will strengthen the management of fertilizer and water,plant crops with high recovery rates,and adopt protective cultivation facilities in some fields.When mulching is needed,the mulching method with membrane width ratio of 60:50 can be adopted to reduce CPMI and improve the retention capacity of soil to organic carbon. |
