采用室内培养试验，研究蚯蚓对玉米秸秆叶鞘、茎髓、茎皮、根分解和养分元素释放动态的影响，运用傅里叶红外光谱技术分析秸秆分解过程中有机物结构变化，为农田秸秆覆盖系统中有机物质转化提供支持。结果表明，玉米秸秆各部位分解速率差异显著，叶鞘分解最快，茎髓和根次之，茎皮最慢。相比对照处理，蚯蚓的存在促进了秸秆分解，其中对根促进作用最强。伴随秸秆分解，养分元素含量也发生变化，蚯蚓提高了秸秆各部位碳释放率，对根作用最强，显著增加了秸秆各部位氮富集。由于茎皮初始C/N和醇酚类化合物含量较高，使其在试验期间表现出较高的氮富集，其次为茎髓和根，叶鞘最低并在试验后期有少量氮净释放。秸秆分解过程红外光谱的变化与碳释放特征基本吻合，蚯蚓作用使秸秆各部位脂肪族-CH、多糖 C-O等吸收峰相对强度减弱，酚醇类-OH、芳香族 C=C吸收峰相对强度增强，特别是叶鞘和根表现明显。

To support the transformation of organic matter in agricultural corn stover mulching systems, an indoor culture experiment was carried out to investigate the effects of earthworms on the decomposition and nutrient release dynamics of corn stover leaf sheaths, stem pith, stem bark, and roots. Additionally, Fourier transform infrared spectroscopy(FTIR) was used to analyze changes in the structure of organic matter during stover decomposition. The results showed that the rates at which the different parts of corn stover broke down varied significantly; the fastest rates were recorded for the leaf sheaths, followed by the stem pith and roots, and the slowest rates for the stem bark. The earthworms' presence enhanced the breakdown of different corn stover components, particularly the root. Nutrient content also changed along with stover decomposition. The rate of C release from all parts of the stover gradually increased with decomposition, and it was higher in the treatment with earthworms than in the treatment without earthworms, suggesting that earthworms promoted the release of C from all parts of the stover, with a stronger effect on root. Due to the high initial C/N ratio and alcohol-phenolic compound content in stem bark, it exhibited the highest N enrichment during the experiment, followed by stem pith and roots; leaf sheaths showed the lowest N enrichment and a small amount of net N release in the later stage. The changes in FTIR spectra during stover decomposition were basically consistent with the characteristics of carbon release. Earthworm activity weakened the relative intensity of absorption peaks of aliphatic -CH and polysaccharide C-O in all stover parts, while enhancing the relative intensity of absorption peaks of alcohol-phenolic -OH and aromatic C=C, with the most obvious effects in leaf sheaths and roots.

S513.01

吉林省科技发展计划项目(YDZJ202401381ZYTS)