Forest type mappign of
Shiwalik hills near Haldiwani, Nainital, district, India through satellite
Remote Sensing Technique Sangeeta
Gupta Remote Sensing Applications Centre, Uttar Pradesh Sector G, Jankipuram, Kursi Road, Lucknow 226 007, India Abstract There is an increasing awareness of environmental conservation and adequate forest management particularly in the areas which are undergoing rapid environmental changes. For this, the planners need up-to-date information which can be obtained through Remote Sensing technique. In the present study author has attempted to prepare a forest cover type map using Landsat TM FCC of 4th May 1989 on 1:62,500 scale. The FCC has been visually interpreted for delineation of forest cover type identified on the basis of tone, texture, pattern and association. The following forest cover type classes could be delineated – 1. Sai (Shorea robusta) Dominated Forest, 2. Miscellaneous Forest, 3. Shisham (Dalbergia Sissoo) Forest, 4. Pine (Pinus roxburghii) Forest, 5. Riverine Forest 6. Sal Plantations, 7. Teak (Tectona grandis) Plantations, 8. Eucalyptus Plantations, 9. Mixed Plantations, 10. Scrubland, 11. Grassland. Introduction : India had once very extensive and rich forests, covering almost the entire surface of the country except for very arid regions of Rajasthan, stretches of saline soils bordering Runn of Kutch, sandy beaches along the coasts and the cold deserts in Himalayas. But now the forest are confined to hilly tracts and poor soils unsuitable for agriculture. The sea-change in the forest in the forest cover of India has brought out by anthropogenic causes such as indiscriminate deforestation, agriculture, grazing, habitation, mining, river valley projects etc. (Unni, 1990). This has raised the urgent need for effective management so that whatever is left could be saved. For effective management of national and regional forest estates, accurate up-to-date and dependable data are required. Information obtainable by satellite Remote Sensing include areas and distribution of forest types, dominant tree species identification and volume estimates for different categories of forests. In India only recently large scale (1:50,000) forest mapping has gained momentum. This kind of study can form a basis for working plan studies and stock mapping by Forest Department as the Forest Department also undertakes such studies on the same scale (Kacchwaha, 1990) Study Area : The area selected for the present study constitutes the part of Shiwalik hills and adjacent Bhabar tract. It is bounded by River Gola on its western side and by lesser Himalaya towards north. The area lies in between 29°18’ to 29°70’ and 79°30’ to 79°46’E longitude. The geological area of the study is 30491.38 sq.m. The study are is shown in fig. 1. Methodology & Data Used: Standard Visual interpretation technique was employed and the satellite imagery was visually interpreted on the basis of differences in tone, texture, pattern, shape, location etc. False Color Composite (FCC) of Landsat – 5 Thematic Mapper (TM) imagery of 1:62,500 scale acquired on 4th May 1989 has been used for interpretation of various forest classes. The Photo-interpretation key was prepared based on ground truth information taken for different classes. For the interpretation of the areas which were inaccessible, the aerial photographs (acquired on 3rd May 1986) were used. Based on these informations a detailed map of the area was prepared. These cover types details were then transferred on base map prepared from survey of India toposheet on 1:50,000 scale using Planvariogrpah. Area under each class was then computed using an electronic Digital Palnimeter. Results The forest of the study area falls in the following forest types of Champion & Seth’s forest classification (champion & Seth, 1968) which is the most widely used forest classification in Indian Context.
A brief description of each class is given below : 1. High Density Shorea rubustin (Sal) Dominated Forest : This type of forest comprises of almost pure stand of Sal. Some other associated species being Lagerstroemia parviflora, Adina cordifolis, Mallotus Philippensis, Syzygium cumini, Cassia fistula, Bauhinia spp etc. The dense undergrowth being mainly for Woodfordia fruticosa, Murraya koenigii, Clerodendron viscosun etc. The density is high and is more then 60%. 2. Medium Density Shroea robusta (Sal) Dominated Forest : The species composition of this category is same as that of the category 1. The density varies from 40-60% depending upon the terrain conditions. 3. High Density Miscellaneous Forest : This type of forest comprises less Shorea robusta (Sal) trees intermixed with other species which are also equally dominating in the area. Some of the other species being Terminialia tomentosa, Adina Cordifolia, Acacia Catechu, Albizzia Procera, Tooan ciliate etc. The density is more than 60%. 4. Medium Density (Shisham) Forest : The species composition is same as category 3. The density varies from 40-60%. 5. Dalbergia sissoo (Shisham) Forest: Shisham Forest are naturally growing on the sand bars of River Goal in almost pure stands. Some associated species being Holoptelea intergrifolia, Ailanthus excelsa, Mallotus phillippensis and dense undergrowth of Murraya Koenigii, Clerodendron viscosum etc. The density varies from 40 – 60%. 6. Pinus roxburghii (Pine) Forest : Pine forest is mostly present in pure stand with almost no undergrowth. It is present mainly on northern steeps slopes and higher ridges. 7. Riverine Forest : This type of forest is present at few places along the streams in waterlogged areas. Due to the presence of evergreen species like Syzygium cumini, Xylosma longifolia, Ficus spp etc. 8. Shorea robusta Plantations : Dense Sal plantation areas could be easily demarcated due to its coarse texture and linear boundary. The area being almost pure Sal plantation lacks stratification and have less undergrowth. 9. Tectona grandis (Teak) Plantations : In this area no natural teak trees are present. Good plantations have been raised at many places in the plains. On the satellite imagery team plantation area is giving bluish grey tone. This is because of water-logging and leafless condition of teak in early May. 10. Eucalyptus grandis (Teak) Plantations Good plantation of Eucalyptus species have been raised. 11. Mixed Plantations Species like Acacia catechu (Khair), Salmalia malabarica (Semal), Dalbergia sissoo (shisham), Tectona Grandis (Teak) etc. have been raised which could be delineated due to its bright red color smooth texture and location. 12. Encroached Forest The forest blank area, fallow land, agriculture land falling within reserve forest boundary has been classified into Encroached Forest. 13. Scrub Land: The species composition is mainly of species like Lantana camara, Cassia tora, Murraya koeingli etc. 14. Grassy Areas : The grasses are present on channel bars of River Gola. 15. Other Classes : Other classes such as agriculture/habitation, exposed rock, streams have also been mapped on the basis of their well known characteristics features. Discussion and Conclusion : The result of this study shows that 23364.8 sq. m of the land is under forest cover which accounts of about 72.62%. But on the other hand 1.4% coached area within Reserve Forest boundary raises an alarming situation. This shows that dense area are cleared by encroachers and used for agriculture purposes leading to degraded fields. The cattle population owned by these encroaches create serious problem of grazing, within the dense forest area. Good plantations of Teak and Eucalyptus have been raised in this area but now the concept of monoculture is not weightage. It is suggested that mixed plantations and that too of the native species of that place should be preferred over pure plantations. Acknowledgement The author expresses her sincere gratitude to Dr. S.K. Shukla, Director, RSAC-UP. Lucknow for all the institutional support for the work. She also extends her thanks to Mr. T.S. Kachhawaha, Head, Forestry Division, RSAC-UP, Lucknow for facilitating this study. References Champion, H.G. and Seth, S.K. 1968 – ‘A revised survey ofn forest types of India’. Manager of Publications, New Delhi. Kachhawaha, T.S., 1990-‘Large Scale Forest / Vegetation Mapping in Rajaji National Park, Uttar Pradesh using Landsat TM and IRS 1A LISS II Satellite data’. project Rep[rot RSAC-UP, Lucknow. Unni, N.V.M., 1990 – ‘Space and Forest Management in India’. In Space and Forest Management, Special Current Event Session, International Astronautical Federation, 41st IAF Congress Dresden, Germany, pp. 47-69.
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