添加不同形态化学氮肥对杏鲍菇菌渣堆肥的影响

Effects of adding different chemical nitrogen fertilizer on the composting of spent mushroom substrate of Pleurotus eryngii

以杏鲍菇菌渣为堆肥原料,分别添加硝酸钾、硫酸铵和尿素,调节堆体碳氮比(C/N)至20,研究添加不同化学氮肥对杏鲍菇菌渣堆肥的温度、p H、电导率(EC)、氧化还原电位(ORP)及有机(无机)态氮等的影响。结果表明:添加尿素和硫酸铵的堆肥升温较快,达到的最高温度较高,并且具有较低的p H值和较高的ORP值,堆肥最终的腐熟程度比添加硝酸钾的堆肥高;添加3种化学氮肥后,随着堆肥时间的推进,堆肥中的DOC、DON、NH4+–N、NO3––N、NO2––N含量都发生了变化,到堆肥结束时,添加硝酸钾的堆肥中DOC和DON含量高于添加硫酸铵和尿素的堆肥中的含量。综合分析,添加不同形态的化学氮肥对堆肥过程中的温度、酸碱度和氧化还原电位等产生影响,进而导致堆肥的腐熟程度不同。

To understand the effects of different nitrogen fertilizer on the composting spent mushroom substrate of Pleurotus eryngii,we added Potassium nitrate,ammonium sulfate or urea into the compost separately and then measured their carbon–nitrogen ratio(C/N).The results showed that compost with addition of urea or ammonium sulfate got higher temperature,lower pH,higher oxidation–reduction potential(ORP)value,and higher maturity than that of compost with potassium nitrate.In the process,the content of dissolved organic carbon(DOC),dissolved organic nitrogen(DON),ammonium nitrogen(NH4+–N),nitrate nitrogen(NO3––N)and nitrite nitrogen(NO2––N)in the compost could change,the content of DOC and DON in the compost with potassium nitrate were higher than those of the compost added ammonium sulfate or urea after composting.This comprehensive analysis showed that addition of different nitrogen fertilizer could affect the temperature,pH,ORP,which together resulted into the different maturity of the compost.