1009
RESEARCH ON MONITORING THE CHANGES
OF DESERTIFICATION BASED ON REMOTE SENSING
Li CUI a
a Institute of Prospecting and Surveying, Changchun Institute of Technology, Comrade Street, Changchun city, China
Commission VII, WG VII/5
KEY WORDS: Desertification, Monitor, RS, GIS, Typical Area
ABSTRACT:
Desertification is caused by the influence of the climatic, environmental changes and human activities. Its enlargement and reverse
leads to not only the changes of spatial structure, scope and environment but also the development of society and economy. Chose
TM remote sensing images which had two different temporal phases as data sources. Through data preprocessing and the choice of
suitable vegetation index,information of desertification in typical area was acquired. Then, in the support of ARCGIS,monitored the
changes of desertification in the typical area. The result shows: From 1995 to 2001, the study area was the development of land
desertification state, development area covered 478.10 km 2 , reversed area covered 426.90 km 2 . The development area was 51.20
larger than reversed area.
1. INTRODUCTIONS
Desertification is one of the most serious environment social-
economy problems nowadays. It involves the world about
900,000,000 populations, more than 100 nations and regions,
area of 36><108 square kilometers. The total area of Chinese
desertification has reached 86.16x104 square kilometers,
especially in the northern agriculture herding interleave region,
the percentage of desertification has already risen from 30% of
the 70's in 20 centuries till 40% of 80's.
China is one of the countries which have the most serious
desertification in the world, the desertification area is about
2.6232 million hm 2 , accounting for 27.3% of land area, the
expansion speed 3436 hm 2 annual, and the rate of development
is increasing every year, the quality of the land is also declining,
ecological environment is deteriorating constantly, dust storms
and other natural disasters have occurred frequently which have
seriously affected the security of people's life. Desertification
problem has already seriously obstructed continuous
development of the society and economy.
Remote sensing technology can acquire the information of
changes and reflect changes timely in the Earth. Remote
sensing in desertification monitoring played a growing role
because of the limitations of traditional ground surveys 11] .
As a new interdiscipline, Geographic Information Systems
played a growing role with the process of information society.
Geographic Information Systems has been widely used in urban
planning, surveying, land, municipal facilities, pipelines,
telecommunications, transportation and other industries. The
integration of the Remote Sensing and Geographic Information
Systems has made certain achievements in land use / cover
change and desertification mechanism of evolution.
2. OVERVIEW OF RESEARCH AREA
Faku county locates in the north of Liaoning Province, belongs
to shenyang city, area of the county is 2,320 square kilometers.
It has jurisdiction over 19 rural towns, two development zones.
Its population is 450,000. The ground gets higher from south to
north, land feature is alluvial plain. The average annual
temperature is 6.7 °C, about 600 mm of precipitation around,
frost-free period of about 155 days, the North temperate
continental monsoon climate.
3. REMOTE SENSING INFORMATION EXTRACTION
OF DESERTIFICATION
3.1 Selection of information
Research on desertification requesting the information is
relatively high. Selecting a reliable and comprehensive data is
the base and guarantee of the research. According to study the
spatial scales and indicators chose different remote sensing data
source. As to the national scale or greater scale of the ecological
environment research, NOAA polar orbit meteorological
satellite remote sensing data can meet the requirements. As to
the province scale or county level scale of the research, remote
sensing data of Landsat series is very effective. Remote sensing
data of Landsat TM contains moderate multi-spectral
characteristics, spatial resolution, accessibility, cost
performance and so on, are still other remote sensing data is
second to none. The research Range is larger, belongs to the
middle scale, so chose the Landsat5 TM data.
Through the sufficient district investigate and choice of remote
sensing images, chose TM remote sensing images which had
two different temporal phases as data sources 1 ^. As shown in
the table 1.
Year
Scene ID
Phase
Band