硅作为地壳中含量第二丰富的元素，其生物地球化学循环与全球碳循环密切相关，在调节大气二氧化碳浓度、海洋初级生产力及海岸带富营养化等过程中发挥关键作用。生物硅（BSi）作为由生物体代谢产生的含硅化合物，其在沉积物中的埋藏是海洋硅移除的主要途径。然而，中国近海沉积物中生物硅的测定缺乏统一标准，导致不同研究数据可比性差。整理评估了预处理方法、提取试剂浓度、温度及时间等关键参数对生物硅测定结果的影响。结果表明，采用0.5 mol/L Na2CO3溶液，在85 ℃下不进行预处理直接提取8 小时，是中国近海沉积物生物硅测定的最适宜方案。收集整理了中国近海（渤海、黄海、东海和南海）沉积物中生物硅的含量及分布数据，对不同预处理和提取条件下的数据进行校正，分析了生物硅的空间分布特征及影响因素。结果表明，中国近海沉积物中生物硅含量范围为0.05%~3.82%，自北向南呈现递增趋势，不同海域表现出独特的平面和垂直分布特征。影响因素方面，水体初级生产力（尤其是硅藻生产力）、沉积物溶解速率（受温度、pH值、比表面积及铝含量等调控）以及人类活动（如营养盐输入和水动力改变）是关键驱动因素。为中国近海生物硅的后续研究提供了数据参考和方法借鉴。

Abstract： Silicon, the second most abundant element in Earth’s crust, is intricately linked to the global carbon cycle through its biogeochemical processes, playing a pivotal role in regulating atmospheric CO2 concentrations, marine primary productivity, and coastal eutrophication. Biogenic silica (BSi), a siliconcontaining compound produced by biological metabolism, serves as the primary pathway for silicon removal from the ocean via sedimentary burial. However, the lack of unified standards for BSi determination in China's offshore sediments has impeded data comparability across studies. An extensive evaluation was conducted to assess the effects of key parameters, including pretreatment methods, extractant concentration, temperature, and duration, on the measurement results of BSi. The findings demonstrate that the optimal analytical approach for determining BSi in China's coastal marine sediments involves extraction with 0.5 mol/L Na2CO3 solution at 85 °C for 8 hours, without any preliminary chemical pretreatment. This research compiles BSi content and distribution data from sediments in the Bohai, Yellow, East China, and South China Seas. It calibrates data generated under different pretreatment and extraction conditions against the optimal methodology, and analyzes spatial distribution characteristics and influencing factors. Results indicate that BSi content in China’s offshore sediments ranges from 0.05% to 3.82%, with an increasing trend from north to south, alongside distinct planar and vertical distribution patterns in different sea regions. Key influencing factors include water column primary productivity (particularly diatom productivity), sediment dissolution rates (regulated by temperature, pH, specific surface area, and aluminum content), and human activities (such as nutrient input and hydrodynamic changes). This study an improved data foundation and methodological framework for subsequent high-precision marine silicon cycle research, carbon sink assessment, and predictive modeling of coastal ecological evolution in China’s offshore areas, while simultaneously highlighting the urgent necessity for establishing national BSi standard reference materials and standardized analytical protocols.