Research Of Coupling Effects Of Water And Biochar On Preserving Water And Nutrients And Fixing Carbon And Reducing Emission's Combined Effects On Base Of Drip Irrigation

The earth is our home.However,with the rapid development of industry,agriculture and economy,the greenhouse effect and climate changes,persistent smog all sounding the alarm to us in our home,therefore,it is to protect our environment.Agriculture is the source of our human energy,however,increasing agricultural intensive pressure,increasing fertilizer quantity and strength lead to soil harden and acidification,whai's more,non-point source pollution problems increasing aggravated.Agriculture is one of the important source of greenhouse gas emissions,the impact on the greenhouse effect to be reckoned with,according to researchers at home and abroad,biochar have been very effective on soil improvement and carbon emission reduction,etc.so in 2015 and 2016 year,Field experiments were conducted on base of drip irrigation under plastic film to research the coupling effection of water and biochar on the physical and chemical characteristics of soil,growth and development of crop,yield and soil greenhouse gas(CO2?CH4 and N2O)emmisions,then estimating the global warming potentials(GWP)of CH4 and N2O and the greenhouse gas intensity(GHGI)through different straw biochar application(0,15,30,45t/hm~2)and different irrigation gradient(control of low irrigation limit by tensiometer:-35,-25,-15kPa)in order to improve soil conditions and reduce greenhouse gas emissions,thus,seeking suitable biochar application and irrigation water,which not only providing theory basis for widely promotion and use of biochar in Inner mongoliar region,but also promoting the sustainable development of agriculture and ecological environment.Main results for this study are as follows:1)Physical and chemical characteristics of soil.Biochar can improve arable layer soil electrical conductivity in different treats,with the increased biochar rates,an up-going and then down-going trend was observed in plough layer of all trial treatments.Improving arable layer soil organic matter,available phosphorus,alkali-hydrolyzable nitrogen and rapidly available potassium contents,among them,high biochar treatments had largest growth of organic matter and available phosphorus.Soil temperature gradually increased with the increase of applying biochar contents in the three leaf stage and jointing stage,After tasseling stage,others were all lower than blank control group in addition to 30t/hm~2 biochar treatments.In the three leaf period,soil surface temperature showed a decrease trend with increase of irrigation water and then all were characterized by W2>W1>W3,in addition,better irrigation water and biochar group is-25kPa and 30t/hm~2.Biochar and irrigation water had no effect on soil pH.Fitting applying quantity of biochar all could improve soil moisture content,among them,applying quantity of 15t/hm~2 ? 30t/hm~2 could improve the soil moisture content in large degree.2)Maize growth and yield.Irrigation water and biochar significantly improved plant height,stem diameter,leaf area index(from jointing stage to the mature)in maize whole growth periods.Biochar significantly increased yield,maize harvest index,but irrigation water had no significant influences on the yield and harvest index.Biochar had no significant effects on dry matter quantities,the irrigation water significantly improved the quantities of maize dry matter in dry year,had no effect in a wet year.Interaction of irrigation water and biochar on the maize above indicators were not significant.3)Emission rules of farmland greenhouse gas.A fitting amount of biochar application could efficiently decrease the farmland season total emissions of CO2,N2O,CH4 and decreased the global warming potentials(GWP)and the greenhouse gas intensity(GHGI)of CH4 and N2O,what's more,their decreasing amplitudes were all more than 40%,taken together,adding biochar of 30t/hm~2 to soil was more appropriate,and farmland average season accumulative total emissions of CO2,N2O and CHa respectively reduced by 3016.81L 0.46,0.31 kg/hm~2 in two years.4)Maize water use efficiency and economic benefits.Interreaction of irrigation water and biochar observably improved the irrigation water use efficiency of maize,N.P,K fertilizer utilization rates and maize economic benefits,thus,irrigation lower limit of-25 kPa and biochar application of 15 t/hm and 30 t/hfi2 could achieve significant water-saving potential,fertilizer utilization potential,maize economic benefits.To sum up,A fitting amount of biochar application and irrigation water could effectively improve the soil physical and chemical properties,crop growth characteristics index,reduce greenhouse gas emissions,is conducive to improve the utilization rate of soil water and fertilizer,the greenhouse effect and the economic benefits,therefore,appropriate use of biochar and irrigation is will of great significance to agricultural economic development and agricultural environment protection in Inner Mongolia region,among them,irrigation lower limit of-25 kPa and biochar application of 15 t/hm~2 and 30 t/hm~2 can realize effectively goals of improving soil quality,corn production and carbon emission reduction.