欢迎访问林业科学,今天是

林业科学 ›› 2017, Vol. 53 ›› Issue (3): 94-104.doi: 10.11707/j.1001-7488.20170311

• 论文与研究报告 • 上一篇    下一篇

机载高分辨率遥感影像的傅氏纹理因子估测温带森林地上生物量

庞勇1, 蒙诗栎1,2, 李增元1   

  1. 1. 中国林业科学研究院资源信息研究所 北京 100091;
    2. 北京师范大学信息科学与技术学院 北京 100875
  • 收稿日期:2016-01-20 修回日期:2016-08-01 出版日期:2017-03-25 发布日期:2017-04-25
  • 基金资助:
    中国林业科学研究院中央级公益性科研院所基本科研业务费专项资金项目(CAFYBB2016ZD004);国家高技术研究发展计划(863计划)(2012AA12A306)。

Temperate Forest Aboveground Biomass Estimation Using Fourier-Based Textural Ordination (FOTO) Indices from High Resolution Aerial Optical Image

Pang Yong1, Meng Shili1,2, Li Zengyuan1   

  1. 1. Institute of Forest Resource Information Techniques, CAF Beijing 100091;
    2. College of Information Science and Technology, Beijing Normal University Beijing 100875
  • Received:2016-01-20 Revised:2016-08-01 Online:2017-03-25 Published:2017-04-25

摘要: [目的] 从反映森林冠层大小的树冠纹理结构出发,利用高空间分辨率遥感影像中树冠纹理的周期性信息,提取基于傅里叶变换纹理序列的纹理指数(FOTO,Fourier-based textural ordination)估测森林地上生物量,探究FOTO纹理因子在温带森林生物量估测上的潜力,为提取新型纹理参数估算森林生物量提供新的参考途径。[方法] 以2009年9月获取的小兴安岭地区凉水国家自然保护区(47°11'N,128°53'E)高分辨率机载航空影像(空间分辨率0.5 m)为例,通过提取CCD影像的FOTO纹理参数,采用多元逐步回归方法对森林地上生物量进行参数反演,并对CCD 3个波段影像提取的9个FOTO纹理因子以及波段平均影像提取的3个FOTO纹理因子2种方法的生物量估测结果进行比较。同时,在研究中尝试采用5种不同尺寸(60 m×60 m,80 m×80 m,100 m×100 m,120 m×120 m和150 m×150 m)的窗口,产生不同尺寸的FOTO因子与生物量进行回归建模。最后,将FOTO纹理因子作为自变量与激光雷达反演的参考生物量进行拟合,利用多元逐步回归方法建立生物量模型,并采用十折交叉验证评估预测模型的泛化能力。[结果] FOTO纹理因子与森林生物量的相关性较高,CCD影像3个波段的9个FOTO纹理因子与生物量的R2均高于0.67,窗口60 m×60 m,80 m×80 m,100 m×100 m,120 m×120 m和150 m×150 m的估测精度分别为67.3%,73.4%,74.4%,78.3%和80.9%。CCD影像波段平均影像的3个FOTO纹理因子与生物量的R2均高于0.57,5种窗口尺寸的估测精度分别为58.2%,62.1%,64.3%,67.4%和70.9%。根据最优预测模型获得分辨率100 m的凉水试验区全覆盖生物量结果图,精度为74.41%,RMSE为50.55 t·hm-2。[结论] 基于FOTO算法提取的纹理因子与森林地上生物量密切相关且无明显饱和现象,对我国北方温带混交林区的生物量反演有极大潜力。FOTO纹理因子与森林地上生物量的多元线性逐步回归模型R2达0.81,RMSE为46.78 t·hm-2

关键词: 温带森林, 高分辨率遥感影像, 森林地上生物量, FOTO算法, 纹理因子

Abstract: [Objective] The periodical information of forest areas in the high spatial resolution remote sensing image contains the structural and spatial distribution of forest canopy grains.We used the Fourier-based textural ordination (FOTO) indices for estimating forest aboveground biomass (AGB). This research explored FOTO textural indices as a potential technique to estimate forest AGB of temperate forest.[Method] The study area is located in the Liangshui Natural Reserve (47°11'N, 128°53'E), northeast of China. Based on the high spatial resolution airborne CCD data (0.5 m spatial resolution) acquired in September 2009, we derived the FOTO indices from CCD data and established the AGB regression model with multiple stepwise regression. The airborne LiDAR-derived AGB map was used as reference value. We compared the model performances of FOTO indices derived from three spectral reflection bands of CCD data with those from the average spectral reflection band of the CCD data. The window sizes for FOTO method were set as 60 m×60 m, 80 m×80 m, 100 m×100 m, 120 m×120 m and 150 m×150 m. Then the FOTO indices derived from different size windows were used as independent variables to build regression model with LiDAR-derived biomass. Ten-fold validation was performed to verify the generalization capability of the estimation model.[Result] The results showed that texture indices derived from FOTO method had a high correlation with forest AGB. The determination coefficient R2 between the FOTO indices (9 FOTO indices from three spectral reflection bands) and LiDAR derived AGB were all above 0.67 for five windows sizes. The estimation accuracies were 67.3%, 73.4%, 74.4%, 78.3% and 80.9% for window size 60 m×60 m, 80 m×80 m, 100 m×100 m, 120 m×120 m and 150 m×150 m, respectively. The determination coefficient R2 between the FOTO indices (3 FOTO indices from the average band) and LiDAR derived AGB were all above 0.57 for five windows sizes. The estimation accuracies were 58.2%, 62.1%, 64.3%, 67.4% and 70.9% for five windows sizes, respectively. We produced a wall-to-wall forest AGB map with the accuracy of 74.41% and the RMSE of 50.55 t·hm-2.[Conclusion] This study results indicated that texture indices derived from FOTO method have great potential in estimating forest AGB without significant saturation phenomenon in temperate forests. FOTO indices have great potential for estimating AGB of temperate forests. The forest biomass derived from FOTO indices with the multiple stepwise regression showed a good relationship with the LiDAR-derived AGB, with R2=0.81, RMSE=46.78 t·hm-2.

Key words: temperate forest, high spatial resolution data, forest AGB, FOTO, texture indices

中图分类号: