长江大通站溶解硅25年变化特征统计分析

通过社会科学通用统计软件（SPSS）对长江1959－1984年溶解硅浓度，流量，降雨量，氮，磷等水文资料之间的相关性进行了分析，并分别进行了线性回归分析，较系统地阐明：1959－1984年，长江溶解硅呈明显下降趋势，与逐年增加的降雨量，流量和氮，磷通量成鲜明对比，使我们目前硅爱量的变化趋势有较深刻的认识。

CHANGE CHARACTERISTIC OF DISSOLVED SILICATE IN THE CHANGJIANG RIVER NEARLY 25 YEARS BY STATISTICAL ANALYSIS

The authors statisticaly analysis the hydrographic data of dissolved silicate, discharge, precipitation, sediment, nitrate and phosphate from 1959 to 1984 in the Changjiang River, and does correlation analysis and regression analysis by Social Purpose Statistical Software. The records show a remarkable decrease tendency in dissolved silicate concentration. The average concentration of dissolved silicate in 1963 is 9.45 mg/L, in 1973 is 7.39 mg/L and 6.25 mg/L in 1983 respectively. However, precipitation, discharge, nitrate and phosphate show increase tendency. The relation between dissolved silicate and other hydrographic data (precipitation, discharge, nitrate and phosphate) show negative relation, and the relation between dissolved silicate and sediment show positive relation. Those were caused by human activities.