基于GIS的黑龙江省降雨侵蚀力时空变化分析

基于黑龙江省32个气象台站近40 a的日降雨量数据计算半月降雨侵蚀力,构建了GIS基础数据库。通过Kriging方法对平均降雨侵蚀力进行插值,运用趋势分析法,从时间和空间上对黑龙江省降雨侵蚀力演变特征进行了分析。结果表明:(1)各气象台站半月平均降雨侵蚀力在时间分布上呈单峰型集中于4月下半月至10月上半月,先逐渐增加,7-8月达到最大值,随后逐渐降低。(2)半月平均降雨侵蚀力在空间分布上存在较大差异,7-8月差异最为显著,7月下半月平均降雨侵蚀力呈全年最大值。(3)该省范围内平均降雨侵蚀力1972-1981年最小,1982-1991年最大,1992-2001年、2002-2011年较1982-1991年平均降雨侵蚀力呈持续递减趋势。(4)该省近40 a平均降雨侵蚀力具有较强的空间相关性,多年平均降雨侵蚀力自西向东、由北至南呈明显的抛物线状分布趋势,伊勒呼里山向北、松嫩平原自东向西、三江平原自西向东、小兴安岭由南至北、张广才岭、老爷岭由北至南,呈明显递减趋势分布。

Analysis on Spatiotemporal Change of Rainfall Erosivity in Heilongjiang Province Based on GIS

Based on daily rainfall data of nearly 40 years over 32 meteorological stations in Heilongjiang Province, half-month rainfall erosivity was calculated, and basic database was built for GIS. The Kriging interpolation algorithm was used to analyze the spatial distribution variation of half-month rainfall erosivity and the trend analysis method was used to analyze their temporal dynamics.The results showed that:(1) The average half-month rainfall erosivity of each meteorological station from the second half of April to the first half of October presented a single-peak curve which increased gradually at first, and reached the maximum value in July and August, then descended gradually.(2) The half-month rainfall erosivity exhibited great spatial differences especially in July and August, and half-month rainfall erosivity of the second half of July got to the annual maximum value.(3) Over the entire province, the minimum value of average ten-year rainfall erosivity occurred in 1972-1981, and the maximum value was in 1982-1991, compared with that in 1982-1991, the average ten-year rainfall erosivity kept decrease in 1992-2001 and 2002-2011.(4) The average rainfall erosivity nearly 40 years had a strong spatial correlation. Average annual rainfall erosivity showed a parabolic distribution trends which direction was from west to east and from north to south within the scope of the province. It presented an obvious decreasing trend northward from Yilihuli Mountains, from east to west in Song-Nen Plain, from west to east in Sanjiang Plain, from south to north in Xiaoxing'an Mountains, and from north to south in Zhangguangcai Mountains and Laoye Mountains.