Study on the nitrogen changes during the composting of chicken manure and different straws under higher temperature

In the aerated static pile automatic compost device,experiments were carried out to investigate the nitrogen changing characteristics of chicken manure added with wheat straw (CM+WS) and chicken manure added with corn straw (CM+CS) respectively during the 50 d composting.The results indicated that there were three temperature stages during the composting process.During the high temperature stage (0-10 d and 0-15 d),the content of ammonium-N increased,but in temperature decreasing stage,the content of ammonium-N decreased very quickly.The contents of ammonium-N was reduced (69.9%) and 57.0% respectively in the treatment CM+WS and CM+CS after the composting process.And the content of nitrite-N increased 152% and 304%,the organic nitrogen decreased 1.4% and 20.7%,the total nitrogen reduced 7.7% and 22.2% respectively.The loss way is ammonium-N volatilization in the temperature decreasing stage and the nitrite in company with water soluble organic nitrogen leach in the temperature decreasing and then became stable stages.The organic carbon decomposed quickly in the high temperature stage and stable after 25 days.The content of the organic carbon decreased 37.9% and 37.3% in the treatment CM+WS and CM+CS respectively during the composting time.pH was 9.16 and 9.37 respectively in the high temperature,and decreased to 8.05 and 8.27 in the end of composting respectively.The concentrations of NO_3-N and Organic nitrogen in the percolation solution of the compost were higher.