郝鹏宇等:The Potential of Time Series Merged from Landsat-5 TM and HJ-1 CCD for Crop Classification: A Case Study for Bole and Manas Counties in Xinjiang, China
被阅读 1522 次
2014-10-21

The Potential of Time Series Merged from Landsat-5 TM and HJ-1 CCD for Crop Classification: A Case Study for Bole and Manas Counties in Xinjiang, China
作者:Hao, PY (Hao, Pengyu)[ 1,2 ] ; Wang, L (Wang, Li)[ 1 ] ; Niu, Z (Niu, Zheng)[ 1 ] ; Aablikim, A (Aablikim, Abdullah)[ 3 ] ; Huang, N (Huang, Ni)[ 1 ] ; Xu, SG (Xu, Shiguang)[ 1 ] ; Chen, F (Chen, Fang)[ 4 ]
REMOTE SENSING
卷: 6  期: 8  页: 7610-7631
DOI: 10.3390/rs6087610
出版年: AUG 2014
摘要
Time series data capture crop growth dynamics and are some of the most effective data sources for crop mapping. However, a drawback of precise crop classification at medium resolution (30 m) using multi-temporal data is that some images at crucial time periods are absent from a single sensor. In this research, a medium-resolution, 15-day time series was obtained by merging Landsat-5 TM and HJ-1 CCD data (with similar radiometric performances in multi-spectral bands). Subsequently, optimal temporal windows for accurate crop mapping were evaluated using an extension of the Jeffries-Matusita (JM) distance from the merged time series. A support vector machine (SVM) was then used to compare the classification accuracy of the optimal temporal windows and the entire time series. In addition, different training sample sizes (10% to 90% of the entire training sample in 10% increments; five repetitions for each sample size) were used to investigate the stability of optimal temporal windows. The results showed that time series in optimal temporal windows can achieve high classification accuracies. The optimal temporal windows were robust when the training sample size was sufficiently large. However, they were not stable when the sample size was too small (i.e., less than 300) and may shift in different agro-ecosystems, because of different classes. In addition, merged time series had higher temporal resolution and were more likely to comprise the optimal temporal periods than time series from single-sensor data. Therefore, the use of merged time series increased the possibility of precise crop classification.
通讯作者地址: Wang, L (通讯作者)
Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China.
地址:
 [ 1 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China
 [ 2 ] Univ Chinese Acad Sci, Beijing 100049, Peoples R China
 [ 3 ] Natl Bur Stat China, Xinjiang Survey Org, Xinjiang 830001, Peoples R China
 [ 4 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China