The Effect On Limestone Soil Carbon Effect Of Corn Ctover And Biochar In The Karst Area

Biochar is the residue straw,wood,leaves,animal manure and sewage sludge and other biomass pyrolysis under anoxic conditions,with a high C content,porosity rich,alkaline,lime applied to the soil to improve its organic carbon content,improve microbial abundance,changes in functional diversity of microbial community structure.In this paper,corn stalks at 350?,600 ? made biochar(BC350,BC600),and corn stover(MS)respectively,according to the quality of indoor simulation tests than 3,6%applied to lime the soil,biochar explore Karst District lime soil stability and its effect on soil micro-environment,evaluate biochar carbon sequestration by sinks effect and its impact on the lime soil biochemical processes.The main findings are as follows:1.Effect of corn straw and lime soil biochar soil organic carbon in karst areaAdd corn stover and biochar are conducive to the accumulation of soil organic carbon,soil organic carbon each increment of the order of 6BC350>6BC600>3BC350>3BC600>6MS>3MS(6BC350,6BC600,6MS respectively added mass ratio of 6%The BC350,BC600,MS is treated soil;3BC350,3BC600,3MS respectively add mass to 3%by BC350,BC600,MS is treated soil).Biochar stable carbon structure and properties of carbon-rich elements conducive to the accumulation of soil organic carbon in biochar made at 350? low cumulative contribution to the limestone soil organic carbon maximum,3%and 6%of biochar and contributions were increased corn straw on the magnitude of the high soil organic carbon 12.75g-kg-1,24.95g-kg-1.Add initial corn stover biochar and its culture,soil organic carbon mineralization rate will increase.With increasing the amount of mineralization rate increased,the amount of the next year,the mineralization rate of MS>BC350>BC600>CK.Train late,BC600 on soil organic carbon mineralization inhibition,but was not significantly different(P>0.05).MS in the amount of 3%and 6%of treated soil organic carbon mineralization rate higher than the control group(CK)4.71 times and 4.12 times.Adding biochar to the cumulative CO2 emissions significantly lower than the added soil straw under 3%of the amount,BC350 and BC600 treated cumulative CO2 emissions are lower than MS treatment group 81.22%,84.19%,6%of the amount under MS treatment group were lower than 78.79%,84.65%,and CK little difference.2.The effect of corn stalks and biochar Karst region lime soil biochemical processesAdd corn stalks and their biochar can improve soil pH,at 3%of the amount,BC350 treated pH increased to 7.10,with an average higher than the control group(CK)0.29,BC600 treated pH increased to 7.29,with an average the control group(CK)0.48.MS treatments change the culture in the initial soil pH is not,as the culture time,pH value increased continuously cultivate late pH value to 7.34 from 6.81.Add MS can significantly increase the number of soil microorganisms,bacteria,actinomycetes,fungi increase the proportion varies,add BC350 can also increase the number of microorganisms,but no obvious straw,add BC600 biochar no significant effect on microorganisms.Add corn stover and biochar can change the structure of soil microbial community diversity,adding straw to improve soil microbial dominance amine metabolism in communities,biochar application in culture conducive to the growth of early metabolic amine groups.With the extension of the culture time,the dominance of soil microbial communities improve Metabolism.Four different treatments in six culture stage invertase and urease content have obvious differences,soil invertase activity in the order of MS>BC350>BC600>CK,urease activity in the order of MS>CK>BC600>BC350.