好氧堆肥腐熟的促进技术

Promotion technology of aerobic compost ripening

好氧堆肥化技术已成为废弃农作物秸秆返田的重要途径之一。随着稀土农用越来越普及,研究稀土元素对废弃秸秆堆肥腐熟进程及产品品质的影响具有较为重要的学术意义。结果表明,稀土元素镧有利于提高堆体中Bacillus thermophiles GX5及其他土著微生物的代谢活性,促进木质纤维素的降解转化,提高堆体的腐熟度。当堆肥体系中存在镧同时添加菌株Bacillus thermophilus GX5时,堆体温度可在第3天升高至70.3℃,且在55℃以上维持5天。此时,堆体的脱氢酶活性为11.02U/g,纤维素降解酶、木质素过氧化物酶和漆酶的酶活分别为4.55U/g、2.82U/g和0.21U/g。腐熟阶段,半纤维素、纤维素和木质素的降解率分别达47.6%、40.6%和31.1%,堆体的E4/E6值为3.24,硝化指数为1.87,种子发芽指数为221.80%。堆肥产品的品质符合我国《有机肥料》(NY/T 525—2021)等相关标准。

Aerobic composting technology has become one of the important ways to return waste crop straw to the field.With the increasing popularity of rare earth agricultural use,it is of academic significance to study the effect of rare earth elements on the composting process and compost quality of waste straw.The results showed that lanthanum,a rare earth element,was beneficial to improve the metabolic activity of Bacillus thermophiles GX5 and other indigenous microorganisms in the piles,promote the degradation and transformation of lignocellulose,and improve the compost maturity.When lanthanum was present in the composting system with addition of Bacillus thermophilus GX5,the pile temperature increased to 70.3℃on the third day and maintained above 55℃for 5 days.The dehydrogenase activity of the pile was 11.02U/g.The enzyme activities of cellulose degrading enzyme,lignin peroxidase and laccase were 4.55U/g,2.82U/g and 0.21U/g,respectively.During the maturity stage,the degradation rates of hemicellulose,cellulose and lignin reached 47.6%,40.6%and 31.1%,the E4/E6 value was 3.24,the nitrification index was 1.87,and the seed germination index was 221.80%.The compost quality met the relevant standards of organic fertilizer in China(such as NY/T 525-2021).