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The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008 
product), which will provide more information of vegetation for 
BJ-1 microsatellite data applications(Chen Zhengchao 2006). 
In the past ten years, various medium resolution sensors have 
been launched. Several land products derived from these 
sensors, or will be soon available to the user community at both 
regional and global scales. Table 1.(Marie Weiss 2007).For 
almost 25 years, the Earth surface has been monitored at 
medium to coarse resolution (not better than 1 km 2 * 1 pixels) 
thanks to the series of NOAA/AVHRR sensors. More recently, 
new sensors have been launched with improved spectral (e.g. 
SEAWIFS/VEGETATION/MODIS/MERIS) or directional (e.g. 
POLDER/MISR) sampling, and higher spatial resolution e.g. 
MERIS/MODIS). 
Reference 
Project 
Sensor 
LAI 
URL 
Knyazikhin et al.(l998) 
NASA/MODIS 
MODIS 
2000-now 
http://cliveg.bu.edu/modismisr/laifpar/laifpar.html 
Roujean and Lacaze 
CNES/POLDER 
POLDE 
1996-1997 
http://polder.cnes.fr/ 
(2002) 
R 
2003 
Chen et al. (2002) 
AVHRR 
1993-2002 
Bacour et al. (2006) 
ESA/MERIS 
MERIS 
2002-now 
http://www.brockmann-consult.de/beam/plugins.html 
Baret et al. (2007) 
FP5/CYCLOPES 
VGT 
1998-2003 
http://postel.mediasfrance.org/ 
Plummer et al. (2006) 
ESA/GLOBCAR 
VGT 
1998-2003 
http://geofront.vgt.vito.be/geosuccess/ 
BON 
ATSR 
MERIS 
1998-2003 
http://geofront.vgt.vito.be/geosuccess/ 
ATSR 
1998-2003 
MERIS 
1998-2003 
VGT 
1998-2003 
The eight-day composites of the LAI/Fapar products 
(MOD15A2) version 4 pertaining to study sites were 
downloaded from the LP-DAAC Internet site. The MODIS 
LAI/Fapar product is produced at the 1-km spatial resolution 
daily(MOD15Al) and composited over an eight-day period, 
where the selected value in a compositing period is that with 
the highest corresponding Fapar. The products are projected on 
the integerized sinusoidal and sinusoidal 1 Oo grid, respectively. 
CYCLOPES products derived from VEGETATION sensors are 
available freely at the following web site: 
http://postel.mediasfrance.org/. The period 1998-2003 is 
currently available. Products are organized by tiles of 10°zenith 
and 10°azimuth. For effective use in such large-scale models, 
regional and global LAI must be available over a period of time. 
Field measurements of LAI, however, are cumbersome, time 
consuming, and impossible to obtain at the global scale. But 
satellite remote sensing is the most effective means of 
estimating LAI global fields on a regular basis(Pandya 2006). 
In this paper, the main object is to study on the method of the 
leaf area index inversion for producing BJ-1 LAI product. 
Based on the field measured data and computer simulation 
model simulated data, we can estimated the LAI of Beijing-1 
images. Then according to the Beijing-1 LAI estimation, the 
second object of this paper is to generate of high spatial and 
high temporal resolution LAI product. A method is proposed to 
get high spatial and temporal resolution LAI product by fusing 
the time-series MODIS LAI product(l km, 8-day product)and 
Beijing-1 LAI images. 
2 MATERIAL AND METHOD 
This section describes: 1) spectral and structure datasets of 
vegetations; 2) satellite data used in the study; 3) the generation 
of of Beijing-1 LAI maps; and 4) remote sensing data analysis 
and generation of LAI maps. 
2.1 Material 
imaging are 16 March, 06; 14 May, 06 and 17 June, 06 
respectively. In order to get the time serial LAI variation, 
MODIS products (MOD15A2 and MOD12Q1) are used. Next 
we will introduce these data in detail. 
Description 
Site: Beijing 
Field experiment Sites 
Shun Yi, Beijing,China 
Location 
Luan Cheng, Heibei 
Date of BJ-1 acquisition 
province, China 
16 March, 06 
14 May, 06 
Date of MODIS LAI 
17 June, 06 
1 Jan 06- 31 Dec,06 
8-day product 
MODIS Tile number 
H26V4, H26V5, 
MODIS Land cover product 
H27V5, H27V5. 
MOD 120,2004 
BJ-1 multi-spectral image has green, red, NIR bands 
(spatial resolution: 32m). 
Tabled LAI Sites and details of satellite data/product 
acquisition used in the study. 
2.1.1. spectral and structure datasets of vegetations 
1) Field Sites and Experimental Measured data: 
In the “Spectral Database System of Typical Objects in China” 
supported by 863 program, we have collected spectrums of 
typical objects and their corresponding parameters for about 20 
years. In the database, there are more than 20,000 of the 
spectral data about vegetation, such as winter wheat, maize, 
rice, cotton and rapeseed, and also their corresponding growth 
structure parameters, the land use and land cover type in the 
experimental sites, crop phenology and farming methods(Wang 
Jindi 2004). 
(a) Winter wheat data: winter wheat spectrum data and their 
parameters, LAI, LAD and so on in Shun Yi, Beijing in China 
in 2001,2003 and 2004; 
(B) Maize data: maize spectrum data and their parameters LAI, 
LAD and so on in Luancheng, Heibei province in China in 
Table.l lists the all data used in this study. The field 
experiment sites are Shun Yi, Beijing,China and Luan Cheng, 
Heibei province, China. And the dates of Beijing-1 images