摘要
研究选取1992—1998年白天NOAA-AVHRR 71条轨道资料,在科尔沁沙地上位于裸露沙占50%以上流动沙丘为主,且连片分布的严重的沙漠化地点,选择26点进行统计分析。结果表明:NDVI、DVI、RVI的周年变化呈水平直线,第1、2通道反照率周年波动很小,年际差异不明显;来自NOAA-11和NOAA-14的1、2通道反照率值有明显差异;在与之毗邻的地区选取8个不同类型植被的区域,发现沙地与植被覆盖区2通道波动有明显相关关系。根据沙地下垫面变化较小的特征,对AVHRR数据进行了修正,增加了可比较性。
In the research,71 orbit NOAA-AVHRR data form 1992 to 1998 were chosen.In place where bare sand over 50% of the main dune sand of horqin and serious desertification area,26 points were selected for statistical analysis.The results showed that the annual change of NDVI,DVI,RVI showed a straight line;the albedo＇s annual fluctuate of the first and the second band was small;there was no significant difference between annual.There was an obvious difference of the albedo values from the first and the second band of NOAA-11 and NOAA-14.In the adjacent area,eight different vegetation types were selected,and the fluctuate between the two bands and the sand area and vegetation covered area had an significant relationship.According to the characteristics＇ small change of the sand underlying,AVHRR data was corrected and the comparability was increased.
出处
《现代农业科技》
2011年第11期309-311,共3页
Modern Agricultural Science and Technology
