Natural Resources and Land use Change of Phuket using Remote Sensing

Natural Resources and Land use Change of Phuket using Remote Sensing

Surachai Ratanasermpong, Jatuporn Pornprasertchai, Dararat Disbunchong
Remote Sensing Division
National Research Council of Thailand
196 Phaholyothin Road, Chatuchak,
Bangkok 10900, Thailand.
Tel. 662-5790116, Fax. 662-5613035

Abstract
Satellite remote sensing data have been proven useful in assessing the natural resources and in monitoring the changes. Results that were obtained from the integrating of remote sensing and geographic information system have been used by policy makers to plan more effectively in natural resources management .The natural resources assessment of Phuket island was performed by using the integration of visual and digital analysis of Landsat -TM data, recorded in 1987, 1990, 1992 and 1995. Based on the 1 : 50,000 topographic map, the three dimensional image of Phuket island was performed. Furthermore, using the method of overlaying, the natural resources change analysis during 1987, 1990, 1992 and !995 was carried 4 out on SPANS -GIS. decreasing natural resources and increasing others land use patterns were identified, located and evaluated at various dates.

It was revealed that during 8 years ( 1987- 1995 ) the mangrove forest has been deteriorated about 4 sq .kIn. or about 19 % caused by urban expansion, on shore mining, solid waste disposal area and particularly coastal aquaculture: shrimp farming. It was found that shrimp farming c increases from .0.50 sq.. to 10 sq.km., rubber. plantation was also converted to shrimp farming and most of the ex-tln mining areas were t transformed to golf courses or resorts.

Introduction
Phuket is the largest island of Thailand, located in the tropical zone , between 7 deg. 28 min .and 8 deg. 13 min. N of the west coast of the southern part of Thailand in the Andaman Sea. The main island itself has an area of about 539 sq.km. and total area of the province, including ,nearly 30 small islets is about 543 sq.km.. Phuket is divided into 3 districts namely Muang, Thalang and Kathu and about 55 % is undulating -rolling topography and 36 % is mountainous areas which mostly located in the south ( Figure 1 ). Land use of Phuket can be classified into 4 categories: agricultural land, forested land, urbanized area and others which cover 44.07 %, 7 %, 2.72 % and 45.58 % respectively.

Figure 1 Phuket island from Landsat- TM band 4 recorded on March 20, 1995
With its luxuriant natural resources such as magnificent long white beaches, mangrove forest and others attractive scenery , Phuket is better known as a tourist paradise. It is a premier tourist destination in the region which average 500,000 visitors per year. As a consequence of the politic, economic .and social pressures in the last decade, the natural resources of Phuket are subject to destruction or over exploitation for mainly tourism development. It thus has been realized that monitoring of natural resources is essential for sustainable development planning. This could be effectively done via remote sensing technique and its development as applied to land use changes study.

Application of Remote Sensing and GIS to Land Use Change
Visual interpretation of Landsat -TM bands 4-5-3/R-G-B, recorded in -1787, 1990, 1992 and 1995 was carried out incooperate with collected ground truth information. While supervised classification of Landsat - TM, recorded in 1995 was performed. Classified results were digitized to SP ANS -GIS .Using the method of overlaying, the natural resources change analysis during 1987, 1990, 1992 and 1995 was conducted. So, decreasing natural resources and increasing others land use were identified, located and evaluated at various dates. Furthermore, based on the contour line of the 1 : 50,000 topographic map, the three dimentional image of Landsat -TM recorded in 1995 of Phuket island was produced.

Results
From the satellite images, land use of Phuket can be classified into 4 main categories ( Figure 2 ) as follows: 1) built -up area: urban area, industrial area, habour, air port, golf courses, resort and waste solid disposal area. 2) forested land: inland forest, forest plantation, mangrove forest, swamp forest and degraded forest. 3) agricultural land: paddy field, rubber plantation, coconut plantation and mixed orchard and shrimp farming, and 4) miscellaneous: ex -tin mining area, beaches, mudflat and water body.

Figure 2 Present Land use Map of Phuket
It was revealed that during 8 years ( 1987 -1995 ) mangrove forest has been deteriorated about 4 sq.krn. or about 19 % caused by shrimp farming, urban expansion, tourism development and tin mining. Table 1 shows the results of mangrove forest and shrimp farming area change of Phuket during 1897 to 1995. It was found that mangrove forest decreased from 21.55 sq.krn. to 17.50 sq.krn. The increasing of shrimp farming during 1987 -1990 -1992 -1995 were 0.46 sq.krn., 1.52 sq.krn., 2.42 sq.krn. and 10.35 respectively. It can be concluded that forested land, rubber plantation, coconut and mixed orchard and paddy land will be decreased and transformed to be urbanized area for the tourism deveopment.

Table 1 Changes of mangrove forest and shrimp farming from 1987 - 1995. (unit : rai, 1 sq.km.=625 rai).

Land Use	Year 1987	Year 1990	Year 1992	Year 1995
Mangrove forest	13,468	12,287	11,400	10,918
Shrimp farming	288	950	1,513	6,469

Conclusion
The study reveals that the multi-dates satellite images analysis yields an exellent result of natural resources and land use change. The Landsat - TM bands 4- 5- 3/ R -G- B, recorded during January through April, diffirentiates more classes of land use pattern than other combination. The preliminary results of the study can be used as a tool for natural resources management focusing on mangrove forest conservation and protection.

Reference

Department of Land Development. 1991. Land Use Planning of Phuket. Bangkok ( Thai Version ). 94 p.
Office of Environmental Policy and Planning. 1995. Provincial State of the Coast Phuket. Bangkok ( Thai Version ).
Royal Forest Department. 1994. Forestry Statistices of Thailand. Bangkok. 130 p.