永翠河流域积雪覆盖及植被NDVI时空变化分析

Spatiotemporal variation of snow cover and vegetation NDVI in Yongcui River basin

利用2004-2014年MOD10A2积雪产品和MOD13A1归一化植被指数(NDVI)与数字高程、气温数据相结合,分析永翠河流域积雪覆盖和植被NDVI时空变化及两者之间的相关性。结果表明:0°~5°坡度带积雪覆盖率(SCF)常年最高,不同坡度带、坡向带SCF与温度呈负相关,积雪覆盖集中在12月至次年1-2月,6-9月基本无积雪;研究区平均年度NDVI值为0.54,轻度改善等级占58.17%,整体处于中等波动变化状态;随着NDVI的增大,积雪覆盖率逐渐变小,积雪覆盖率和NDVI相关系数|r|=0.67006,表现为负相关。

Based on the combination of MOD10A2 snow products and MOD13A1 normalized vegetation index(NDVI)with digital elevation and air temperature data from 2004 to 2014,Yongcui River basin’s spatiotemporal changes of snow cover and NDVI and their correlation were analyzed.The results showed that the snow cover fraction(SCF)was the highest in the 0°~5°slope zone throughout the year,the SCF of different slope zones and slope direction were negatively correlated with temperature.Snow cover was concentrated in December,January and February of the next year,and there was almost no snow cover from June to September.The average annual NDVI value of the study area was 0.54,and the grade of slight improvement accounted for 58.17%,which was in a state of moderate fluctuation on the whole.With the increase of NDVI,the snow coverage rate gradually decreases.Generally speaking,there is a negative correlation between snow coverage rate and NDVI in the study area,and the correlation coefficient is|r|=0.67006.