摘要
针对春季农作物风沙灾害监测快速、准确的要求,提出了农作物风沙灾害的遥感监测方法。以2009年4月阿克苏市风沙灾害为例,基于MODIS每日地表反射率产品,对阿克苏市农作物风沙灾害前后和恢复期的NDVI进行了动态监测,并利用同时期正常年份的NDVI变化确定农作物受灾阈值,通过统计分析确定受灾农作物的面积。结果显示:阿克苏市农作物风沙灾害前后和恢复期,农作物NDVI最大值从0.36增大到0.73,占农作物总面积比例最大的NDVI值从0.08增大到0.11;阿克苏市受灾农作物面积12697.07hm2,负向-正向型农作物受灾面积占总受灾面积的35.16%,正向-负向型农作物受灾面积占总受灾面积的63.06%,负向-负向型农作物受灾面积占总受灾面积的1.78%。该方法对农作物受灾面积的提取精度为98.24%,是一种方便、高效和实用的农作物风沙灾害监测方法。
Considering the monitoring requirement of wind sand damage to crops in spring,this research introduced remote sensing monitoring method for studying the wind sand damage to crops. Taking Aksu City as study area,the NDVI values of the crops in the periods of before and after the wind sand damage,and the recovery period in Aksu were dynamically monitored based on MODIS land surface reflectance products,and the threshold of wind sand damage for crops was determined by analyzing the change of NDVI at the same period in a normal year. Through statistical analysis,the area of wind sand damage for crops was obtained. The results show that the maximum NDVI of before,after and recovery period of wind sand damage in Aksu increased from 0. 36 to 0.73,and the NDVI value accounted for the largest proportion of total crop area increased from 0. 08 to 0. 11. The area of crop with the wind sand damage was 12697. 07hm2. By contrast,the damage area ratios of negative-positive,positive- negative and negative- negative were 35. 16%,63. 06% and 1. 78%. The extraction accuracy of this method on the crops disaster area was 98. 24%,that means the method is convenient,efficient and practical for monitoring the wind sand damage for crops,and may be used in the wide range.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2014年第11期78-82,共5页
Journal of Arid Land Resources and Environment
基金
公益性行业(气象)科研专项(GYHY201106025)资助
