中文摘要：

研究气象站点密度在当日雨量和前期有效雨量因子内插中的影响程度，对提高对这2个因子的内插精度有重要的意义。本文针对我国东南地区87个泥石流灾害点和207个站点的降水资料，建立站点密度在5％～100％间变化的空间采样方案，采用反距离加权法（IDW）计算不同站点密度下泥石流灾害点的当日雨量和前期有效雨量。利用分位数方法对站点密度与当日雨量和前期有效雨量的关系进行分析，结果表明：诱发泥石流灾害的当日雨量和前期有效雨量的内插值，均随着气象站点密度的降低呈减少趋势；前期有效雨量的内插值相对于当日雨量的内插要稳定一些。在站点密度大于5％的情况下内插的前期有效雨量可以保持60％以上的雨量值，而当日雨量只大于30％。

英文摘要：

It is important to understand the effect of the rain gauge density on the interpolation of effective antecedent precipitation and critical rainfall. For the 87 debris flow sites, the interpolation rainfall is calculated based on 5%--100% variational sampling scheme of 207 rain gauge stations. The inverse distance weight method is used to interpolate the ef- fective antecedent precipitation and critical rainfall. Using the quantiles method, the rela- tionship between the gauge density and the interpolation rainfall of the day debris flow and the effective antecedent precipitation is analyzed. The result shows the interpolation rain- fall is exponentially decreasing due to the decrease of the gauge density. The interpolation of the effective antecedent precipitation is more stable and needs smaller amount of gauge with the same precision than that of the critical precipitation. When the gauge density is less than 5 %, the interpolation of the effective antecedent precipitation keeps the real value beyond 60%, otherwise the critical rainfall is under 30%.