Effect Of Biochar Application On Soil Autotrophic And Heterotrophic Respiration And Analysis Of The Driving Factors

Since climate warming and the decline of arable land quality has been getting worse and worse.the demand for soil quality enhancement and carbon sequestration reduction is increasing significantly which would require improvements toward soil fertility and carbon sequestration capacity.Biochar has shown great potential for improving soil quality and reducing emission of greenhouse gas.What's more,it has also become a popular research topic.However,further research is needed regarding to the effect of biochar on increasing foreign exchange emissions.This article has chosen summer corn and winter wheat rotation as the research object of farmland,the method of field testing,systematic ally study of different levels of biocarbon application of soil self-cultivation/alien respiration rate,soil environmental factors,soil nutrients and soil microbial properties of the changing characteristics,to explore biocarbon carbon reduction and the possible factors affecting soil fertility,with a view to identifying the reasonable amount of biocarbon.The main factors that were affecting the total respiratory rate of farmland soil are determined by the relevant analysis method and the main component analysis method,which provided a scientific basis for exploring the application potential of the soil of summer corn/winter wheat rotation in the North China Plain for the carbonization of fruit wood branches.The main findings are as follows:(1)Under the conditions of control(0 t·hm-2),low biochar dosage treatment(5 t·hm-2),medium biochar dosage treatment(10 t·hm-2),high biochar dosage treatment(20 t·hm-2),The total soil breathing rate,self-supporting breathing rate and hetero-breathing rate show a single peak change pattern day and night,the change of day time is larger,the change of night and early morning change is small,the maximum value occurs at about 14:00,and the corn and wheat seasons reach an average of 12.09 ?mol·m-2·s-1,and 5.38?mol·m-2·s-1,respectively;minimum values occurred at around 23:00,with the corn and wheat seasons averaging 1.15?mol·m-2·s-1 and 1.08?mol·m- 2·s-1,respectively.Moreover,there isn't any significant differences in sable processing.The soil breathing rate is basically in line with the daily mean of soil respiration and could represent the breathing rate of a day.(2)At different biochar application levels,the total soil breathing rate,self-supporting breathing rate and hetero-breathing rate has shown significant seasonal variation characteristics,with the maximum in summer and the minimum in winter.The largest monthly flux of soil respiration occurred in June-July,with the total monthly feed of each treated soil at 248.45 g C m-2 or more,the monthly flux of soil self-cultivation breathing at 26.25 g C m-2 or more,and the monthly flux of soil heterogeneous respiration at 216.70g C m-2 or more.Furthermore,the minimum value occurs at the beginning or the end of the growth season,where each treatment was below 24.55 g C m-2.Compared with the control treatment,biochar application could obviously improve the monthly flux and annual flux of each component,and the overall treatment followed the trend of medium carbon application and high carbon amount and low carbon application and control treatment.(3)Under the summer corn/winter wheat rotation system,5 cm soil moisture content,tillage nitrogen,ammonium nitrogen,effective phosphorus,quick-acting potassium and soluble carbon(DOC)content with the increase of biochar application showed a trend of first increase and then decrease.All of them have reached the maximum value of T2.Comparing with T1,the maximum increment reached 32.04%,102.58%,124.58%,124.2%,81%,76.20%,56.97%and 82.92%,different biochar dosage treatment on the tillage microbial carbon(MBC)content has a significouldt effect,and MBC content increased with the increase of biochar application,compared with non-biochar T1 treatment,T4 up to 33.41%,but no significant effect on 5 cm soil temperature.(4)The correlation analysis and analysis of the main component of the total soil breathing rate showed that the key influencing factors of the total soil breathing rate were soil moisture content,DOC,MBC and soil ammonium nitrogen.To conclude,low-volume biochar treatment(T2)could reduce soil self-culti vation/alien respiration rate compared to control(T1)treatment,and could effec tively improve soil environmental factors,soil nutrients and soil microbial prop erties.In addition,Soil moisture content,DOC,MBC and soil ammonium nitrog en are the most important factors affecting the total respiratory rate of farmlan d soil.It has also provided scientific basis for biochar to increase the potential of carbon sequestration in farmland ecosystems.