Study On The Effect Of Adding Biochar On Aerobic Composting Of Cow Manure

In order to explore the effect of adding biochar on the aerobic composting process of cow dung,this study used corn stalks as auxiliary materials,mixed cow dung and corn stalks to adjust the carbon-nitrogen ratio,and studied the effects of different types and different amounts of biochar on cow dung and cow dung.The basic physical and chemical properties of aerobic composting of corn stalk mixture and the influence of four different enzyme activities are discussed.The influence of suitable biochar types and addition amount on the composting effect is discussed,in order to provide a reference for the use of carbon-based organic fertilizer.This experiment mainly studied the effects of adding different kinds and proportions of biochar on the temperature,water content,pH value,electrical conductivity,carbon nitrogen ratio,ammonium nitrogen,nitrate nitrogen content and activities of urease,catalase,sucrase and polyphenol oxidase in the process of manure composting.The results are as follows:(1)In the process of mixed composting of cow dung and corn stalks,the addition of biochar can effectively accelerate the temperature increase of the pile.Among them,the temperature of the pile of 5% rice husk biochar treatment increases faster,and the high temperature period continues longer time;During the composting process,the total carbon content of the pile decreases,the total nitrogen content increases,and the carbon-to-nitrogen ratio of the pile decreases.Add 5% rice husk biochar,5% rice straw biochar and 10% rice straw biochar The total carbon content of the treatment has a faster decline rate and the decomposing rate of the pile is faster;The treatment of adding 5% rice husk biochar and adding 2% rice straw biochar has a better effect on reducing nitrogen loss during the composting process,and has a better nitrogen fixation effect;the addition of biochar also has a certain effect on increasing the ammonium nitrogen content and nitrate nitrogen content in the pile.The addition of 2% rice husk biochar,5% rice husk biochar and 10% rice straw biochar can be more significant increase the content of ammonium nitrogen in the reactor;The treatment of adding 5% rice husk biochar,10% rice husk biochar and 2% rice straw biochar can significantly increase the nitrate in the pile nitrogen content has a certain positive effect on promoting compost maturity.(2)After adding biochar,the urease activity first increases and then decreases.Rice husk biochar has a more significant effect on improving urease activity than rice straw biochar,and the amount of biochar added should not be too much,with 2% or 5% better results;The addition of biochar has a certain promotion effect on the increase of catalase activity in the aerobic composting process of cow manure.The addition of 5% rice husk biochar has the best effect;The invertase activity increases first and then decreases trend,except for the addition of 5% rice husk biochar treatment and 2% rice straw biochar treatment,the addition of biochar in other treatments did not significantly increase the invertase activity;The polyphenol oxidase activity first decreased and then increased trend,adding 5% rice husk biochar has the best effect on improving the activity of polyphenol oxidase during composting.