The study on multi sensors observing for ground truth using vehicle
Hirokazu Yamamoto, Hiroyuki Masubuchi, Hironobu Oishi ,Koji Kajiwara and Yoshiaki Honda*
*Center for Environment Remote Sensing (CEReS), Chiba University
1-33 Yayoi-Cho, Inage-Ku, Chiba, 263 Japan
Fax : +81-43-290-3857
E-mail: Kath@rsirc.cr.chiba-u.ac.jp
Abstract
We improved on previous developed ground truth measurement system using vehicle, which can obtained spectral information and ground nadir image with satellite scale in the short time. Our developed new system mounts more various kinds of measurement instruments. We practically tested to obtain data with this measurement system in summer of 1998 in three types of Mongolian grassland. As a result, above-mentioned multi sensors system is very useful instrument for acquisition of data on a satellite spatial scale in the short time and its data is quite useful for satellite data.
1.Introduction
It is focused on monitoring vegetation amount in wide area using satellite data such as NOAA AVHRR. Because thus satellite data that has the characteristics of lower spatial resolution and higher time-frequency is very useful tool in order to monitor the vegetation amount. And it is needed to understand relation between spectral information and vegetation amount. But, in so many studies, ground-based data that is satisfied in comparable with satellite scale is quite few. We aim to standardize the methodology of ground truth for quantitative analysis of vegetation. We already have developed the system using vehicle, and we have confirmed that this system has potential for investigating relationship between spectral information and vegetation coverage ratio (VCR) with satellite scale efficiently. But this system has been able to get only information of spectral reflectance and ground nadir image, and the analysis takes so much time because obtained images have to be captured from 8mm video. If the system can obtained various kind of data and acquire still images, we will be able to investigate relationship between spectral information, VCR and more other ancillary data efficiently.
In this study, we aim to develop the new system which mounted multi-sensor and verify data obtained by this developed system.
2. Study area
The study area is around Mandalgobi in Mongolia (see Fig. 1).We conducted measurement in three types of grassland around Mandalgobi. First observation site, Site 1 is located in north side of Mandalgobi (N450 59' 41.5" E1060 19' 39.5") and this side is more dense vegetated area than other site. Measurement in this site is conducted during 3-9 Aug., 1998 but this report is shown only last measurement day, 9Aug., because this day of weather is best condition for this measurement. Second site, Site 2 is located in western side of Mandalgobi (N450 38' 51.5" E1050 39' 13.3") and this is sparse vegetated grassland area, and data is obtained in Aug. 10,1998. Third site, Site 3 is located in southern side of Mandalgobi (N450 23' 23.6" E1060 14' 9.9") and measurement was conducted 11 Aug., 1998.
Fig. 1 The study Area
