Abstract:

To effectively realize the resource utilization of dredged silt in river channels, this study used dredged silt as the main raw material, supplemented with different proportions of organic materials (distiller's grains, cassava residue, and mushroom residue), and developed different rice seedling nutrition soil formulas. By comparing the differences in physicochemical properties of these nutrient soils and their effects on rice seedling quality, and using principal component analysis to comprehensively evaluate the growth indicators of rice seedling, the optimal nutrient soil formulas were screened out. The results showed that, compared with pure silt, adding organic materials to silt significantly reduced the pH value and bulk density of nutrient soil, while significantly increased electrical conductivity (EC), total porosity, organic matter and available phosphorus content. In the consective two seasons of seedling cultivation experiment, the treatments of adding organic materials to silk generally showed better seedling growth than the pure silk treatment, but there were differences in the effectiveness between the treatments. In the first season experiment, the treatment with 40% distiller's grains added to the silt showed the best seedling rate and plant height performance, which were 85.79% and 18.33 cm, respectively. The treatment with 20% cassava residue added to the silt showed the best performance in terms of SPAD value, total root length, and aboveground dry matter weight of 100 plants, reaching 29.52 cm, 81.63 cm, and 2.10 g, respectively. In the second season experiment, the treatment with 40% distiller's grains added to the silt had the highest leaf age, plant height, and stem-based width, which were 4.49, 23.10 cm, and 2.39 mm, respectively. The treatment with 20% cassava residue added to the silt had the highest underground dry matter weight of 100 plants, reaching 1.28 g. The results of principal component analysis showed that the treatment of adding 40% distiller's grains or 20% cassava residue to silk resulted in better comprehensive quality of machine transplanted seedlings, which could be considered as the suitable formula for rice seedling nutrient soil.

Key words: rice, organic materials, dredged silt, nutritive soil, seedling quality, principal component analysis

摘要：

为实现河道疏浚淤泥的资源化利用，本研究选取疏浚淤泥作为主要原料，辅以不同比例的有机物料（具体包括酒糟、木薯渣和菇渣），研制了不同水稻育秧营养土配方。通过比较这些营养土在理化性质上的差异及其对水稻秧苗素质的影响，并利用主成分分析法对秧苗生长指标进行综合评价，筛选出表现较优的营养土配方。结果显示，与纯淤泥相比，淤泥中添加有机物料能够显著降低其pH值和容重，同时显著提高电导率（EC）、总孔隙度、有机质含量以及速效磷含量。在连续两季的水稻育秧试验中，淤泥添加有机物料处理所培育秧苗生长状况普遍优于纯淤泥处理，处理间效果存在差异。在第1季育秧试验中，淤泥中添加40%酒糟的处理在成苗率和株高方面表现突出，成苗率达85.79%、株高达18.33 cm；而淤泥中添加20%木薯渣的处理则在SPAD值、总根长和百株地上部干物质量方面表现优，分别达到29.52、81.63 cm和2.10 g。在第2季育秧试验中，淤泥中添加40%酒糟的处理在叶龄、株高和茎基宽方面表现优，分别为4.49叶、23.10 cm和2.39 mm；而淤泥中添加20%木薯渣的处理在百株地下部干物质量上表现最高，达1.28 g。主成分分析结果进一步表明，淤泥中添加40%酒糟或添加20%木薯渣处理所培育的机插秧苗在综合素质上表现优异，可以考虑作为水稻育秧营养土的适宜配方。

关键词: 水稻, 有机物料, 疏浚淤泥, 营养土, 秧苗素质, 主成分分析