蓝藻堆肥中养分及微囊藻毒素含量变化

为探索和优化开放环境中脱水藻泥堆肥化处理工艺,以滇池打捞的蓝藻藻泥为原料,采用室外堆肥方法,研究米糠、麦麸、酒糟作为填充剂对蓝藻堆体的养分含量、发芽指数和微囊藻毒素(MCs)含量的影响,并对这些因子之间的相关性进行了分析。结果表明:堆肥结束后,碳素损失率为23.2%～36.2%,氮素损失率为40.7%～56.9%,总磷、总钾和灰分含量均增加;堆肥结束后,各处理的总养分含量(N+P2O5+K2O)均能满足有机肥料标准,堆肥50 d后各处理发芽指数都超过80%,MC-RR低于检测底限10μg/kg,MC-LR的降解率也达到90%以上。综合各类指标,麦麸作为填充剂的效果最好。堆肥过程中MC-RR含量和MC-LR含量间有极显著的相关性,微囊藻毒素含量与堆体有机碳和总氮含量呈显著正相关,而与总磷、总钾、总养分含量以及灰分呈显著负相关。

Changes of contents of nutrients and microcystins during composting of blue algae

To explore and optimize the composting technology of dewatering blue algae,an outdoor composting was conducted,in which,rice husk,wheat bran and pot ale were used as stuffing.The results showed that carbon and nitrogen contents decreased by 23.2%-36.2% and 40.7%-56.9%,respectively,at the end of composting in all treatments.The contents of total phosphorus,total potassium and ash increased.The total nutrient content(N+P2O5+K2O) met the standard of organic fertilizer.At the end,the germination index in each treatment was over 80%,microcystin-RR content was under the detection limit of 10 μg/kg,and microcystin-LR content decreased by more than 90%.Taken all indexes together,wheat bran was the best as stuffing in blue algae composting.The correlation between microcystin-RR content and microcystin-LR content was extremely significant.The microcystin content was positively correlated with contents of organic carbon and total nitrogen,and negatively correlated with contents of total phosphorus,total potassium,and total nutrient and gray.