School of Resource and Environment, Northeast Agricultural University, Harbin 150030, China.
School of Resource and Environment, Northeast Agricultural University, Harbin 150030, China.
Ecotoxicol Environ Saf. 2021 Feb;209:111804. doi: 10.1016/j.ecoenv.2020.111804. Epub 2020 Dec 22.
Nutrient-rich biogas slurry shows favorable prospects for application as an organic fertilizer in farmland. At the same time, due to differing sources and treatment methods, the C/N ratio of biogas slurry varies greatly. The effect of differences in C/N of biogas slurry on soil organic matter properties remains unclear. In this experiment, pig farm biogas slurry differing in C/N (3, 6, 8.84 and 12) was applied instead of fertilizer. Fluorescence spectroscopy combined with parallel factor analysis and principal component analysis were used to determine dissolved organic carbon (DOC) and fluorescent dissolved organic matter (FDOM) in soil dissolved organic matter (DOM). The experimental results showed that the DOC and FDOM contents of soil could be significantly increased at the initial stage of biogas slurry application. Compared with CK, on the 60th day, biogas slurry with a C/N of 12 exhibited the greatest improvement in DOC, FDOM as well as for Component 1, Component 2 and Component 3 contents in soil FDOM, 40.93%, 66.25%, 65.35%, 40.47%, and 78.42% respectively. However, compared with the 0th day, by the 60th day, biogas slurry with a C/N of 8.84 exhibited the greatest decrease in Component 4 content in soil FDOM, 74.68%. Biogas slurry with a C/N of 8.84 exerted the greatest promotion effect on corn growth, the utilization and transformation of Component 4 by plants and microorganisms in the soil. And it showed the strongest improvement in the degree of FDOM humification in the soil, the humification index increased from 4.16 ± 0.17 to 4.92 ± 0.58, compared with CK. This study provided new insights for the utilization of biogas slurry with respect to soil physical and chemical properties and maize plant growth.
富营养沼气浆作为一种有机肥料在农田中有很好的应用前景。同时，由于来源和处理方法不同，沼气浆的 C/N 比差异很大。沼气浆 C/N 差异对土壤有机质性质的影响尚不清楚。本试验以不同 C/N（3、6、8.84 和 12）的猪粪沼气浆代替化肥进行田间试验，采用荧光光谱结合平行因子分析和主成分分析方法，测定土壤中溶解性有机碳（DOC）和荧光溶解性有机质（FDOM）。结果表明，沼气浆施入初期可显著增加土壤中 DOC 和 FDOM 的含量。与 CK 相比，第 60 天 C/N 为 12 的沼气浆处理对土壤 DOM 中 DOC、FDOM 及 FDOM 中组分 1、组分 2 和组分 3 的含量增加最大，分别为 40.93%、66.25%、65.35%、40.47%和 78.42%。但与第 0 天相比，第 60 天 C/N 为 8.84 的沼气浆处理对土壤 FDOM 中组分 4 的含量下降最大，为 74.68%。C/N 为 8.84 的沼气浆对玉米生长、植物和微生物对土壤中组分 4 的利用和转化具有最大的促进作用，对土壤中 FDOM 腐殖化程度的改善最为明显，腐殖化指数由 4.16±0.17 增加到 4.92±0.58，与 CK 相比。本研究为沼气浆在土壤理化性质和玉米生长方面的利用提供了新的见解。
