Effect of Moisture Content on Composting with Spent Substrate of Pleurotus ostreatus
In order to investigate the effect of moisture content on the composting of Pleurotus ostreatus spent substrate,different moisture contents(46%,54%,59%,65%)spent substrate were used for composting after carbon nitrogen ratio(C/N)adjusted to about 30∶1,then the temperature,pH,electrical conductivity(EC),seed germination index(GI),nutrients and organic matter content of Pleurotus ostreatus spent substrate were determined during composting progress.The results showed that there was no significant difference in the average fermentation temperature during the whole composting process.However,the fermentation temperature of spent substrate with 65%moisture content was lower than those of spent substrate with 46%,54%and 59%moisture contents in the first 17 d,and higher than those of 46%,54%and 59%in the last 22 d of composting process.The total nutrients of spent substrate with different moisture contents were all more than 4.00%after 17 d composting.When composting for 39 d,the total nutrients and N,P,K contents of all treatments did not differ significantly,the GI of all treatments were more than 100%,and the pH and EC of all treatments also reached the standard of NY/T 525-2021,but only the spent substrate with initial moisture content of 46%and 54%reached the moisture standard of NY/T 525-2021(≤30%).In summary,the Pleurotus ostreatus spent substrate with moisture content of 46%~54%could be fermented into qualified organic fertilizer after adjusting the C/N.Above results provided scientific basis for the fertilizer utilization of Pleurotus ostreatus spent substrate.