Study on monitoring vegetation ecological environment over the whole China by using vegetation index from meteorological satellite
Xiao Qiangguang, Cheng Weiying1
Satellite meteorology Centre, State Meteorological
Administration, China
Abstract
The focus of this paper is put on the method (literate method) of processing AVHRR data of NOAA (or FY-1) meteorological satellite in monitoring vegetation ecological environment over the whole area of China. The mosaic image mad with this method eliminates cloud influence. Results of primary analysis of monitoring the ecological environment by utilizing the vegetation maps over the whole land of China is also presented which shows that the mosaic image not only can be used in monitoring vegetation ecology environment, but also can be used in monitoring climatic changes. Mosaic images made in different years, seasons and months apparently exhibit the yearly, seasonal and monthly changes of vegetation over the whole country and it also shows apparent regional division line and climatic lines which indicate the existing relationship between difference of regional vegetative distribution and climate. The mosaic image processing referred in the study has been operated and is becomes the found mental basis for further study on continental and globle changes.
Preface
The vegetation remote sensing in the past is mainly for the studies of the local vegetation status and their types. With the deterioration of the worldwide ecological environment, study in the continental and global changes has become the most noticeable problem. Research work has been conducted in more and more countries. The goal is to protect the global ecological environmental and maintain is balance. People hope earnestly to find an objective scale to measure this change and believe the growth and change of vegetation is an ideal scale. Because the change of vegetation has a close relationship with the changing of climate and environment. The vegetation can exist and reproduce under the certain condition of lightness, temperature and water and existence of vegetation can change the surface reflectance, and influence the local evaporativity and the exchange of energy and mass in ground surface. So vegetation and environment have bidirectional characteristics. Through a simple calculation of the reflectances of visible and near infrared channels of meteorological satellite, we can derive the vegetation index (greenness index), from which not only it exhibits vegetation, but also its amount can be estimated. The vegetation index maps in different years, season, months show the different status of vegetation distribution and amount. Relating it with the environment, we can infer what changes have happened and what changes will happen in the environment Biology), which focus on researches of the relationship between climate, environment and global vegetation is being on the upgrade.
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1. lu Weijin and Li jing did part of the work; Mr. Cui Haiting participated in analysis of image.
