Estimating ground fractional vegetation cover using the double-exposure method

	Estimating ground fractional vegetation cover using the double-exposure method
	Zhou, Gongqi 1; Liu, Suhong 1
刊名	INTERNATIONAL JOURNAL OF REMOTE SENSING
	2015
卷号	36 期号:24 页码:4174-4186
通讯作者	Liu, SH (reprint author), Beijing Normal Univ, Sch Geog, Beijing 100875, Peoples R China.
英文摘要	Fractional vegetation cover (FVC) is a key parameter in ecological models. It is important to determine the ground FVC quickly and accurately in studies of soil erosion, surface energy balance, and carbon cycling. As one of the FVC ground measurement methods, the photographic method is easy to operate with relatively high precision. However, its classification result showed poor accuracy when an image of a high-contrast scene contained a shadow region where a low signal-to-noise ratio (SNR) existed, because the single-exposure image in the photographic method did not contain sufficient surface information about both the illuminated and shadowed parts. This article presents application of a double-exposure photographic method to determine vegetation cover in the shadow region of an image. It consists of two measurements used in acquiring images (normal and over-exposure) and one image-processing part to handle the obtained images. Illuminated vegetation and soil, as well as the shadow region, was classified with the normally exposed image in the intensity, hue, and saturation (IHS) colour space, and the shadow region was further classified as shadowed vegetation and shadowed soil using the over-exposed image. The results indicate that the over-exposed image reduced the average bias of the FVC in the shadow region from 15.40% to -4.14% and the root mean square error (RMSE) from 0.174 to 0.066. The RMSE of the entire scene was 0.055 in the over-exposed image and 0.092 in the single-exposed image. The double-exposure method also showed a better classification result than the high dynamic range method in deep shadow regions. This study shows that this method is capable of distinguishing vegetation and soil in the shadow region and thus it is an effective and accurate method for ground FVC measurement.
研究领域[WOS]	Remote Sensing ; Imaging Science & Photographic Technology
收录类别	SCI ; EI
语种	英语
WOS记录号	WOS:000365867200005
内容类型	期刊论文
源URL	[http://ir.ceode.ac.cn/handle/183411/38351]
专题	遥感与数字地球研究所_SCI/EI期刊论文_期刊论文
作者单位	1.[Zhou, Gongqi 2.Liu, Suhong] Beijing Normal Univ, Sch Geog, Beijing 100875, Peoples R China 3.[Zhou, Gongqi 4.Liu, Suhong] Chinese Acad Sci, Beijing Normal Univ & Inst Remote Sensing Applica, State Key Lab Remote Sensing Sci, Beijing, Peoples R China
推荐引用方式 GB/T 7714	Zhou, Gongqi,Liu, Suhong. Estimating ground fractional vegetation cover using the double-exposure method[J]. INTERNATIONAL JOURNAL OF REMOTE SENSING,2015,36(24):4174-4186.
APA	Zhou, Gongqi,&Liu, Suhong.(2015).Estimating ground fractional vegetation cover using the double-exposure method.INTERNATIONAL JOURNAL OF REMOTE SENSING,36(24),4174-4186.
MLA	Zhou, Gongqi,et al."Estimating ground fractional vegetation cover using the double-exposure method".INTERNATIONAL JOURNAL OF REMOTE SENSING 36.24(2015):4174-4186.