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基于2000～2010年的MODIS/Terra积雪8 d合成数据（MOD10A2）与DEM数据,通过计算和分析积雪频率与积雪覆盖率,研究了新疆玛纳斯河山区雪盖的时空分布特征。结果表明：①研究区一月份积雪覆盖丰富,积雪频率高值区主要分布在北部中低山地区、南部中海拔地区以及清水河与塔西河的河源地区;四月与十月的雪盖分布规律相似,总体上积雪频率随高程上升而上升;七月份只有少部分高山区域被积雪覆盖;②积雪频率始终保持较高水平的区域是玛纳斯河、金沟河、清水河以及塔西河的河源高山地区,而玛纳斯河流域中上游的河谷地区则始终保持较低水平;③一月份,1 400 m以下地区的积雪覆盖率超过95%,随着高程上升,迅速下降至2 600 m的最低值约41%,此后逐渐上升至5 000 m以上80%左右;④一月、四月和十月份积雪覆盖率在大部分高程带上均表现为北坡、东北坡和西北坡最高,东坡和西坡次之,南坡、东南坡和西南坡最低的规律;七月份各高程带的雪盖分布没有明显的坡向差异。“,”Snow is one of the most active factors in the nature which influences the redistribution of solar radiation energy and water resource.The distribution of snow cover over mountainous area of Manasi river basin will exert great impact on river runoff in snowmelt season.Based on snow cover frequency and snow cover fraction acquired from remotely sensed MODIS/Terra snow cover product from 2000 to 2010,the study discussed the spatial and temporal distribution of snow cover in mountainous area of Manasi river basin.There are abundant snow cover accumulation in January with several high snow cover frequency areas appear in lower altitude area in the north,moderate altitude area in the south and the source of Qingshui river and Taxi river.In general,the snow cover distributions show the same pattern and the snow cover frequencies both rise with altitude in April and October,while only a few areas with high altitude are covered by snow accumulation in July.Additionally,the snow cover frequencies maintain at high level throughout the year in the birthplace of Manasi river,Jingou river,Qingshui river and Taxi river,while it keeps in lower level in valley areas of middle and upper reaches of Manasi river.Furthermore,the snow cover fraction in January decreases from 95% in areas below 1 400 m to 41% in 2 600 m,and hereafter increases to about 80% in areas above 5 000 m.The snow cover fraction of January,April and October show similar tendency in most elevation zone with the highest value in the north,northeast and northwest slopes,followed by the east and west slopes,and the lowest in the south,southeast and southwest slopes.