采用2012年4月长江口外围区域实验获取的固有光学特性数据，分析了该区域水体中粒子的散射特性的水平和垂直变化及其影响因素。对12个站位的分析结果表明，该区域水体粒子散射和后向散射均非常强烈，表层、5、10、20、30 m水层488 nm的后向散射系数和后向散射比平均值分别为0.0617、0.0683、0.0642、0.0606、0.1294 m-1和1.77%、1.92%、1.94%、1.98%、2.15%。各水层水体的颗粒物折射率平均值为1.14，除个别站位外，折射率介于1.1~1.2之间，表明该水域粒子以无机矿物质颗粒物为主，尽管颗粒物吸收光谱在676 nm的吸收峰表征了色素颗粒物的影响较为显著。研究结果表明，受长江泥沙输入和底质再悬浮等影响，实验区域水体散射和后向散射强烈，存在明显的层化效应，水中粒子以无机矿物质颗粒物为主。

Variability of particulate scattering properties and its possible influencing factors are studied using the in-situ inherent optical properties (IOPs) data obtained during april 2012 in the outside estuary of the Yangtze River. Twelve stations are monitored, and the result shows that the average of particulate backscattering coefficients and backscatter ratios at 488 nm at the surface, 5, 10, 20, 30 m depth are 0.0617, 0.0683, 0.0642, 0.0606, 0.1294 m-1 and 1.77%, 1.92%, 1.94%, 1.98%, 2.15%, respectively. The average of particle refractive index at the five layers is 1.14. Except one or two stations, it varies between 1.1 and 1.2. These show the domination of the inorganic mineral particles in this area, although the absorption peak around 676 nm implies a significant concentration of pigment particles in the water. In conclusion, subject to the abundant input of fresh water from the Yangtze River and the re-suspension of bottom particles, particulate scattering and backscattering dominate the IOPs and their variabilities. Also, non-organic mineral particles are the dominant constituents in seawater. Moreover, the variation of particulate scattering shows strong correlation with the depth.