摘要: |
【目的】 利用2018—2019年冬小麦生长季的雷达数据对河南省驻马店市上蔡县、正阳县、平舆县、汝南县的冬小麦种植面积进行提取,为雷达数据在冬小麦种植面积提取研究提供参考。【方法】 文章在对冬小麦生长关键物候期多时相Sentinel-1A SAR(Synthetic Aperture Radar,合成孔径雷达)数据中VV极化和VH极化影像的后向散射系数进行分析的基础上,利用最大似然法开展了河南省驻马店市上蔡县、正阳县、平舆县、汝南县4个“产粮大县”的冬小麦种植面积提取研究,并通过统计年鉴数据对VV极化和VH极化的冬小麦提取结果进行了初步评价。利用2018年12月22日,2019年3月28日和2019年4月21日的SAR时间序列影像数据进行冬小麦分类提取。【结果】 从整个研究区来看VV极化方式的提取结果为4 461.14 km2,VH极化的结果为4 277.22 km2,与统计数据相比,VV极化的误差为13.17%,VH极化的误差为8.51%,VV极化的提取误差要大于VH极化的提取误差。各个县的结果显示,VH极化的提取误差均小于VV极化的结果,误差最小的为利用VH极化提取的正阳县的结果,误差仅为1.85%,误差最大的为利用VV极化提取的平舆县的结果,误差为19.72%。【结论】 基于冬小麦生长关键物候期多时相Sentinel-1A的后向散射系数,能够实现较高精度的冬小麦种植面积提取。 |
关键词: 哨兵1号 后向散射系数 冬小麦 面积提取 |
DOI:10.12105/j.issn.1672-0423.20220501 |
分类号: |
基金项目:科技创新2030一重大项目课题“多模式协同的农情反演、预测及智能计算”(2021ZD0113704) |
|
Extraction of winter wheat planting area based on Sentinel-1A data |
Geng Yunjing1, Jiang Aihui2, Leng Pei1
|
1.Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China;2.College of Geography and Environment,Shandong Normal University,Jinan,250358,China
|
Abstract: |
[Purpose] The radar data of winter wheat growing season from 2018 to 2019 was used to extract the winter wheat planting area of Shangcai County,Zhengyang County,Pingyu County and Runan County in Zhumadian City,Henan Province,and to provide reference for the extraction of winter wheat planting area from radar data.[Method] In the present study,the Sentinel-1A SAR was used to estimate the planting area of winter wheat over the study area of the Shangcai county,Zhengyang County,Pingyu County and Runan County,Henan Province. First,the evaluation of backscattering coefficients of the VV polarization and VH polarization from multi-temporal Sentinel-1A during the key phenological period of winter wheat growth was investigated and a combination of three critical dates was determined to obtain a fused image for winter wheat planting area extraction. Then,the winter wheat planting areas over the study area was obtained with the maximum likelihood method using the multi-temporal Sentinel-1A data. Finally,the estimated winter wheat planting areas was assessed by statistical data.[Result] Based on SAR time series images on December 22,2018,March 28,2019 and April 21,2019,the winter wheat planting areas in 2018 for the study region is approximately 4 461.14 km2 with VV polarization and 4 277.22 km2 with VH polarization,and the error is about 13.17% and 8.51%,respectively. The smallest error(1.85%)is that of Zhengyang County extracted by VH polarization whereas the largest error(19.72%)is that of Pingyu County extracted by VV polarization.[Conclusion] The results show that the Sentinel-1A data can estimate accurate winter wheat planting area over the study area. |
Key words: Sentinel-1A Backscatter coefficients winter wheat planting area |