中国地理科学 ›› 2018, Vol. 28 ›› Issue (6): 986-997.doi: 10.1007/s11769-018-1007-x

• 论文 • 上一篇    下一篇

Predicting Surface Roughness and Moisture of Bare Soils Using Multiband Spectral Reflectance Under Field Conditions

CHEN Si1,2, ZHAO Kai1, JIANG Tao1, LI Xiaofeng1, ZHENG Xingming1, WAN Xiangkun1,2, ZHAO Xiaowei1,3   

  1. 1. Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China;
    3. College of Geoexploration Science and Technology, Jilin University, Changchun 130026, China
  • 收稿日期:2018-03-30 修回日期:2018-07-26 出版日期:2018-12-27 发布日期:2018-11-01
  • 通讯作者: ZHENG Xingming.E-mail:zhengxingming@iga.ac.cn E-mail:zhengxingming@iga.ac.cn
  • 基金资助:

    Under the auspices of the Excellent Youth Talent Project of Jilin Science and Technology Development Program (No. 20170520078JH), Science and Technology Basic Work of Science and Technology (No. 2014FY210800-4), National Natural Science Foundation of China (No. 41601382)

Predicting Surface Roughness and Moisture of Bare Soils Using Multiband Spectral Reflectance Under Field Conditions

CHEN Si1,2, ZHAO Kai1, JIANG Tao1, LI Xiaofeng1, ZHENG Xingming1, WAN Xiangkun1,2, ZHAO Xiaowei1,3   

  1. 1. Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China;
    3. College of Geoexploration Science and Technology, Jilin University, Changchun 130026, China
  • Received:2018-03-30 Revised:2018-07-26 Online:2018-12-27 Published:2018-11-01
  • Contact: ZHENG Xingming.E-mail:zhengxingming@iga.ac.cn E-mail:zhengxingming@iga.ac.cn
  • Supported by:

    Under the auspices of the Excellent Youth Talent Project of Jilin Science and Technology Development Program (No. 20170520078JH), Science and Technology Basic Work of Science and Technology (No. 2014FY210800-4), National Natural Science Foundation of China (No. 41601382)

摘要:

Soil surface roughness, denoted by the root mean square height (RMSH), and soil moisture (SM) are critical factors that affect the accuracy of quantitative remote sensing research due to their combined influence on spectral reflectance (SR). In regards to this issue, three SM levels and four RMSH levels were artificially designed in this study; a total of 12 plots was used, each plot had a size of 3 m×3 m. Eight spectral observations were conducted from 14 to 30 October 2017 to investigate the correlation between RMSH, SM, and SR. On this basis, 6 commonly used bands of optical satellite sensors were selected in this study, which are red (675 nm), green (555 nm), blue (485 nm), near infrared (845 nm), shortwave infrared 1 (1600 nm), and shortwave infrared 2 (2200 nm). A negative correlation was found between SR and RMSH, and between SR and SM. The bands with higher coefficient of determination R2 values were selected for stepwise multiple nonlinear regression analysis. Four characterized bands (i.e., blue, green, near infrared, and shortwave infrared 2) were chosen as the independent variables to estimate SM with R2 and root mean square error (RMSE) values equal to 0.62 and 2.6%, respectively. Similarly, the four bands (green, red, near infrared, and shortwave infrared 1) were used to estimate RMSH with R2 and RMSE values equal to 0.48 and 0.69 cm, respectively. These results indicate that the method used is not only suitable for estimating SM but can also be extended to the prediction of RMSH. Finally, the evaluation approach presented in this paper highly restores the real situation of the natural farmland surface on the one hand, and obtains high precision values of SM and RMSH on the other. The method can be further applied to the prediction of farmland SM and RMSH based on satellite and unmanned aerial vehicle (UAV) optical imagery.

关键词: soil surface roughness, soil moisture, spectral reflectance, field conditions, stepwise multiple nonlinear regression

Abstract:

Soil surface roughness, denoted by the root mean square height (RMSH), and soil moisture (SM) are critical factors that affect the accuracy of quantitative remote sensing research due to their combined influence on spectral reflectance (SR). In regards to this issue, three SM levels and four RMSH levels were artificially designed in this study; a total of 12 plots was used, each plot had a size of 3 m×3 m. Eight spectral observations were conducted from 14 to 30 October 2017 to investigate the correlation between RMSH, SM, and SR. On this basis, 6 commonly used bands of optical satellite sensors were selected in this study, which are red (675 nm), green (555 nm), blue (485 nm), near infrared (845 nm), shortwave infrared 1 (1600 nm), and shortwave infrared 2 (2200 nm). A negative correlation was found between SR and RMSH, and between SR and SM. The bands with higher coefficient of determination R2 values were selected for stepwise multiple nonlinear regression analysis. Four characterized bands (i.e., blue, green, near infrared, and shortwave infrared 2) were chosen as the independent variables to estimate SM with R2 and root mean square error (RMSE) values equal to 0.62 and 2.6%, respectively. Similarly, the four bands (green, red, near infrared, and shortwave infrared 1) were used to estimate RMSH with R2 and RMSE values equal to 0.48 and 0.69 cm, respectively. These results indicate that the method used is not only suitable for estimating SM but can also be extended to the prediction of RMSH. Finally, the evaluation approach presented in this paper highly restores the real situation of the natural farmland surface on the one hand, and obtains high precision values of SM and RMSH on the other. The method can be further applied to the prediction of farmland SM and RMSH based on satellite and unmanned aerial vehicle (UAV) optical imagery.

Key words: soil surface roughness, soil moisture, spectral reflectance, field conditions, stepwise multiple nonlinear regression