LAND USE AND LAND COVER CHANGE DETECTION USING REMOTE SENSING AND GIS FROM THOOTHUKUDI TO VEMBAR COAST

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1 LAND USE AND LAND COVER CHANGE DETECTION USING REMOTE SENSING AND GIS FROM THOOTHUKUDI TO VEMBAR COAST R.A.Rejin Nishkalank 1,B.Gurugnanam 2 1,2 Centre for Applied Geology, Gandhigram Rural Institute Deemed University, Dindigul. Abstract - The study area ( E & E Longitudes and N & N Latitudes) Thoothukudi to Vembar, Tamil Nadu, India. Land use and Land coverplays a major role in progressive planning. The present study reveals the changes that occurred in the area for 22 years. To generate the Land use and Land cover map from Satellite (Landsat)ETM+ of geocoded with UTM projection and datum WGS-84, ZoneNorth 44 generated from the total bands 8 on a 1:50,000 scales, was used. Supervised classification andtopographical maps were enhanced for better analysis. A process of integrating remote sensing techniquesand field data to precisely map Land use and Land cover of the study area is undergone. The study also helps in demarcating the sector-wise changes i.e. the major changes happened to the agricultural land which constitutes about 60% in the study area. The changes are severe and rapid due to urbanization and emerging of new industrial complexes. The study gives an overview about the changes to be noted during the planning of further developmental activities in the area. From the study, the area has been subjected to change in the landuse and landcover in all the present features.field observation provides an idea about the existing status andissues of coastal problems. Five major classes were identified and mapped in the study area. These are: Agriculturalland, Salt pans, Barren land, Shrub land and Water bodies. The study observed that cultivated land is dominant inthe area but, it is subjected to a rapid change due to developmental activities. This is followed by salt pans. The study recommends the use of advanced satellite images forfuture Land use and Land cover monitoring studies. Keywords: Thoothukudi, Geology,Land use/land cover, Remote Sensing, GIS, Supervised classification, Agriculture I. INTRODUCTION Coastal zone is a broad transitional area between the land and sea where the waters of the seas meet the land are indeed unique places in our global geography. The shoreline is a boundary line between land and sea. A nation should have adequate information on its natural resources as well as many interrelated aspects of its activities for decision making. Coastal landforms and wetlands are a few of such resources which have acquired importance as they influence various developmental activities along the coastal regions. Land transformation is a major field of anthropogenic transformation with an extensive history dating back to antiquity (Wolman et al., 1987). Almost all of the world s lands are now used and managed at various intensities according to its usage and the needs of the human race (Liu et al., 2002). To assess what effect a particular land transformation and its consequences involves severe issues of forecasting and proper evaluation of the changes (Turner, 1994). The rapid increased of population in the urban areas have resulted in the major changes of the landuse and landcover of a region. This also led to the deterioration of the urban environment (John et al, 2011). Due to synoptic view, map like format and repetitive coverage, satellite remote sensing imagery is a visible source of gathering quality land cover information at local regional and global scales (Foody, 2002; Guo et al., 2009). The present study reveals the landuse and landcover changes that took place in the coastal belt of Thoothukudi to Vembar region of TamilNadu using multi-temporal satellite data. The various changes along the belt that has drastically transformed the landforms along the area have been discussed and the changes noted were All Rights Reserved 150

2 II. STUDY AREA The area extends from ( E & E Longitudes and N & N Latitudes) Thoothukudi to Vembar along the coastal belt of TamilNadu, India. It comprises of atotal length of kilometres. The study area falls under Survey of India (SOI) toposheet numbers, 58 I 1 & 5, 58 K 4 & 8 respectively.the Thoothukudi district was bifurcated from the combined Tirunelveli district on 29 th,october, 1986 (Selvam, 2012), The salient features of the district include its lengthy, curvy and scenic sea coast with enormous palmyrah trees, The district is known for pearl cultivation, with an abundance of pearls being found in the seas offshore, from which the name Pearl City came; the ancient port of Korkai through which trade with Rome happened, The Coral islands of the Gulf of Mannar Marine Biosphere Reserve, The beautiful coastal villages with their sacred temples, churches and mosques. The Tropical climate prevails in the district throughout the year. The rainfall is mainly due to the north east monsoon.the area comprises of Red loamy soil, Lateritic soil, Black soil, Sandy coastal Alluvium and Red Sandy soil. The prominent geomorphic units identified in the district are 1) Fluvial, 2) Marine, 3) Fluvio-marine, 4) Aeolian and 5) Erosional landforms depending on the environment of formation. The district is well connected by two national highways and nine state highways with various rural road networks. III. GEOLOGY The geology of the area is mainly of sedimentary rocks of tertiary to recent age. The remaining area is covered by crystalline rocks. Most of the formations are of Archaean period except few places where Proterozoic age is identified. Most of the area is covered by sandy beaches along the coast, except few places of the estuary. The general stratigraphic succession is the Proterozoic formation at the base succeeded by tertiary formation and Quarternary formations. Rock types such as Charnockites, Quartzite, Granulite, Laterite, Teri sands, Shell limestone, Sandstone are noted along the entire study area. The entire coast is rich in heavy minerals such as Ilmenite and Garnet along the entire shoreline. IV. MATERIALS & METHODS Preparation of the thematic layersforland use and Land cover using Landsat ETM+ datato create the land use land cover map from satellite imagery using supervised classification. The Thoothukudi topomaps (1972) were digitized and the extent of the saltpan, barrenland, Agricultural land, Water bodies and Shrubland were extracted using ArcGIS 10.2 software. The geocodingwith UTM projection, datum WGS-84, Zone North 44 generated from the total bands 8 on a 1:50,000 scales, was used for the present study. The Survey of India toposheet maps 58I 1&5, 58K 4&8 on a scale of 1:50,000 equal to the corresponding imagery were used for the preparation of final thematic maps. From the output obtained, the changes were All Rights Reserved 151

3 Fig.1. Key map of the study area. V.RESULTS & DISCUSSION Figure No.1 1. Land use and Land coverstudies of 1992: The Landuse and Landcover details of the year 1992 was obtained using the Landsat ETM+ data. The supervised classification technique was implemented and the results were tabulated. The area is mostly covered with Agricultural land for about 56 sq.km area, followed by barren land for about 25 sq.km, Shrub land by 22 sq.km, salt pans contributing the economy to a higher rate of the nation about 16 sq.km and the water bodies about 11 sq.km. These were clearly identified through proper field studies. The following table clearly exhibits the details of the landus and landcover of the All Rights Reserved 152

4 accurately. Settlements were noted while field studies, but the tonal difference cannot be noted in the satellite images due to the varying resolution of the satellite images obtained. 2. Land use and Land cover studies of 2001: The landuse landcover details of the year 2001 was identified and demarcated using the satelite image of Landsat ETM+ of Indian Remote Sensing satellite series. The supervised classification technique was used to determine the changes of the study area landuse and landcover. From the studies the area is covered by agriculture land about 40 sq.km, salt pan accounts for about 27 sq.km area, Shrub land for about 25 sq.km area, Barren land for about 20 sq.km area, and water bodies about 18 sq.km area. A rapid change in the area is noted in the rise of the saltpans from 16 sq.kms to 27 sq.kms area. This was due to the water scarcity and less rainfall accounted in the area. The agricultural land was reduced to 40 sq.kms due to intrusion of saltwater in the groundwater watertable. The waterbodies was increased to 18 sq.kms. This is due to the rejuvenation works carried out by the state government to improve the quantity and quality of the water bodies due to encroachment activities. All the changes observed in the satellite image was confirmed through field studies and noted. 3. Land use and Land cover studies of 2009: This studies of landuse and landcover in this period shows typical changes of coverage parameters subjected to change accordingly to the economic crisis of the area. This can be clearly understood in increase of agricultural lands to construction lands at a rapid level. The agricultural land has reduced to 37 sq.km when compared with previous data of The salt pan has increased from 27 sq.km to 36 sq.km that clearly predicts the change in the groundwater table and salt water intrusion due to rapid urbanisation. The barren land area has been reduced to 13 sq.kms which accounts for most of the constructions done, but cannot be predicted in the satellite image, but proved in the field study. The shrubland area has increased to 28sq.kms. The waterbodies are subjected to change and has been again reduced to 15 sq.kms. All the changes were observed in the satellite image and through proper field interpretation. 4. Land use and Land coverstudies of 2014: The high level of change was noticed in the salt pans area as it has a rapid increase in this area with reference to The salt pans covers about 41 sq.kms and has increased by about 5 sq.kms. The agricultural land has been still reducing, but it is at a very slower rate when compared with the previous years. It covers an area about 35 sq.kms. The barren land covers an area of about 15 sq.kms. The waterbodies contributes 17 sq.kms of the study area. The shrubland covers an area of about 23 sq.kms. The changes were noted in the area through proper field All Rights Reserved 153

5 Fig.3. Land use/land cover map for 1992 and 2001

6 \ Fig.3. Land use/land cover map for 2009 and 2014

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9 Sl.No LU/LC 1992 (Area in Sq.Km) 2001 (Area in Sq.Km) 2009 (Area in Sq.Km) 1 Salt pan with sand 2 Agriculture land Barren land Water bodies Shrub land Ocean (Area in Sq.Km) Table 1 Land use and Land cover details Fig.4. Land Use / Land Cover Change ( ) V.CONCLUSION The study helps in identifying the Land use and Land cover details of the area in a detailed manner. The Remote sensing and GIS techniques played a major role in demarcating the changes throughout the area. This also extends an idea about the future perspectives of this study and make changes in the planning methods to get a better coastal zone and attain sustainable development in the area. Moeover, the decrease in the agricultural land has to be taken into account seriously and measures has to be taken to reducee the change of the agricultural lands to construction sites. The factory building sites must be properly designed to reduce the land wastage with proper permits.the increase in barren land too also has to taken into consideration and the root causes must be analysed and proper management measures has to be implemented. The shrubland area are mostly near to the coastland and estuaries. Those lands can be changed with plantations that restrict the force of high waves to reduce the erosion along the coastal villages. The saltpan areas has to be monitored

10 continuously and the measures has to be taken to increase the groundwater table and salt water intrusion. The coastal regulation management rules has to be strictly followed and timely monotoring of the changes has to be noted and actions must be taken by the concerned departments throughout the entire coast from Thoothukudi to Vembar. VI. ACKNOWLEDGEMENT The author s are thankful to the university authorities, Gandhigram Rural Institute Deemed University, Dindigul, TamilNadu for providing necessary facilities to complete this work. REFERENCES 1. Foody G M. Status of land cover classification accuracy assessment. Remote Sensing of Environment, Vol.80, pp , Guo L Y, Wang D L, Qiu J J. Spatio-temporal patterns of land use change along the Bohai Rim in China during Journal of Geographical Sciences, Vol.19, Issue.5, pp , John Prince Soundranayagam, P.Sivasubramanian, N. Chandrasekar, K.S.P. Durairaj, An analysis of land use pattern in the industrial development city using high resolution satellite imagery, Journal of Geographical Sciences,Springer-Verlag 21(1), pp: 79-88, Selvam.S, Use of Remote Sensing and GIS Techniques for Land Use and Land Cover Mapping of Tuticorin Coast,Tamilnadu Universal Journal of Environmental Research and Technology, Eurasian Publication Volume 2, Issue 4, pp , Turner B L, William B Meyer, Changes in Land Use and Land Cover: A Global Perspective. USA, Cambridge University Press, Wolman M G, Fournier F G A, Land Transformation in Agriculture. Chichester, UK: John Wiley and Sons, All Rights Reserved 159