硅是湿地生态系统的重要元素之一，土壤有效硅是植物可吸收硅素的核心组分。为了解扎龙湿地土壤有效硅含量分布特征及影响因素，在扎龙湿地设置了78个表层土壤采样点和12个剖面土壤采样点，测定各采样点土壤有效硅含量，并分析其与土壤理化指标之间的关系。研究结果表明，扎龙湿地表层土壤有效硅质量比平均值为225.71 mg/kg，属于丰富水平，变异系数为33.16%，属于中度变异。扎龙湿地土壤有效硅空间分布存在较大差异，整体呈现为由西向东递减的分布特征，北部、中南部和东南部土壤有效硅含量高于其他区域。在剖面土样中，随着土壤深度的增加，土壤有效硅含量整体呈先减少后增加的规律。扎龙湿地土壤有效硅含量受土壤养分和理化性质的影响，表层和剖面土壤有效硅含量与土壤全磷和无机磷含量极显著正相关，与土壤pH分别显著负相关和极显著负相关，表层土壤有效硅含量与土壤黏粒含量极显著正相关，与砂粒含量显著负相关。土壤类型和土地利用方式对土壤有效硅含量也有影响，其中中层熟黑土有效硅含量高，潜育暗色草甸土有效硅含量低；林地土壤有效硅含量高，草地土壤有效硅含量低。本研究结果为揭示湿地生态系统生源要素硅的生物地球化学循环过程提供理论依据，对了解扎龙湿地土壤的供硅能力具有重要参考价值。

Silicon is one of the important contents of the element cycle in wetland system, and soil available silicon is the core component of plant absorbable silicon. To understand the distribution characteristics and influencing factors of soil available silicon content in Zhalong Wetland, 78 surface soil sampling points and 12 profile soil sampling points were set up in Zhalong Wetland to measure the soil available silicon content at each sampling point and analyze the relationship between soil available silica content and soil physical and chemical indexes. The results showed that the average effective silicon mass ratio of the surface soil in Zhalong Wetland was 225.71 mg/kg, which belonged to the abundance level, and the coefficient of variation was 33.16%, which belonged to the moderate variation. There were great differences in the spatial distribution of soil available silica in Zhalong Wetland, and the overall distribution characteristics showed a decreasing distribution from west to east, and the soil available silica content in the northern, south-central and southeastern parts of the study area was higher than that in other regions. In the profile soil samples, with the increase of soil depth, the available silicon content of soil decreased first and then increased. The soil available silicon content in Zhalong Wetland was affected by soil nutrients and physicochemical properties, and the available silicon content in the surface and profile soil was significantly positively correlated with the soil total phosphorus and inorganic phosphorus content, and was significantly negatively correlated with the soil pH, respectively, and the available silicon content in the surface soil was significantly positively correlated with the soil clay content, and negatively correlated with the sand content. Soil type and land use also had an effect on the available silicon content of soil, among which the available silicon content of the middle cooked black soil was high, and the available silicon content of the latent dark meadow soil was low. The available silicon content of woodland soil was high, and the available silicon content of grassland soil was low. The results of this study provided a theoretical basis for revealing the biogeochemical cycle process of silicon, a biogenous factor in wetland ecosystems, and had important reference value for understanding the silica supply capacity of soil in Zhalong Wetland.