QUANTIFYING DEFORESTATION IN A PERMANENT FOREST RESERVE USING VECTORISED LANDSAT TM

• Published in: Journal of tropical forest science 2003-10, Vol.15 (4), p.570-582
• Main Authors: Jusoff, Kamaruzaman, Setiawan, I.
• Format: Article
• Language: English
• Subjects: Deforestation; Forest reserves; Forest resources; Forestry; Image classification; Landsat; Rubber; Tropical forests; Tropical rain forests
• ISSN: 0128-1283

Vectorising Landsat TM image (127/56 path/row) was carried out in this study to quantify deforestation using integration of remote sensing and geographic information system (GIS) in Permanent Forest Reserve (PFR) of northern Kelantan, Malaysia (latitudes 04° 30' N to 06° 15' N and longitudes 101° 20' E to 102° 40' E). The PFR boundary map in 1989 was digitised to analyse physical factors that affect deforestation. By using minimum distance supervised classification, Landsat TM is an effective tool for distinguishing forested area from non-forested area such as rubber, oil palm and paddy with overall accuracy of about 84.8% and mean accuracy of between 58.3 and 97.7%. The rate of deforestation was about 2.3% per year with 73 236 ha of the PFR in the northern part of Kelantan being converted into non-forested purposes within eight years (1989-1997). The change from forest into mixed crop or rubber within eight years was estimated to be 19 252.1 ha. However, 53 984.1 ha of forest were converted into shrubs, while approximately 1178.5 ha of forest were converted into grassland/open areas. This study implies that RS/GIS technique is a useful tool in quantifying deforestation in PFR. Landsat TM (127/56 jalur/baris) yang divektorkan digunakan dalam kajian ini untuk menilai pelupusan hutan dengan mengintegrasikan penderiaan jauh dan sistem maklumat geografik di Hutan Simpan Kekal (PFR) di utara Kelantan, Malaysia (garis lintang 04° 30' U ke 06° 15' U dan garis bujur 101° 20' T ke 102° 40' T). Peta sempadan PFR berkenaan yang diterbitkan dalam tahun 1989 telah didigitalkan dan digunakan untuk menganalisis ciri-ciri fizikal yang mempengaruhi pelupusan hutan. Landsat TM merupakan alat yang menggunakan klasifikasi seliaan jarak minimum untuk membezakan kawasan hutan daripada kawasan bukan hutan seperti getah, kelapa sawit dan padi dengan ketepatan keseluruhan sebanyak 84.8% dan ketepatan purata antara 58.3% hingga 97.7%. Kadar pelupusan hutan adalah lebih kurang 2.3% setahun dengan 73 236 ha daripada PFR di utara Kelantan ditukar kepada kegunaan bukan hutan dalam masa lapan tahun (1989-1997) dengan anggaran 19 252.1 ha. Bagaimanapun, 53 984.1 ha hutan telah ditukar kepada belukar manakala 1178.5 ha hutan telah ditukar kepada kawasan terbuka atau padang rumput. Kajian ini menunjukkan bahawa teknik penderiaan jauh/sistem maklumat geografik merupakan satu alat yang berguna untuk menilai pelupusan di PFR.