INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 7, No 1, 2016

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1 INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 7, No 1, 2016 Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN Land use land cover mapping using Geo-informatics of Kodagu District, Karnataka Megokedono Vakha, Nagaraju M, Asha Manjari K.G Department of Studies in Earth Science, University of Mysore, Manasagangotri, Mysuru adonovakha@gmail.com ABSTRACT In the present day land usage has been dominated by man and thus the land use land cover reflects greatly the interaction between man and its environment. This paper deals with the mapping of land use land cover with the help of Geoinformatics. Thus with GIS software it has led to delineation of seven classes of land use land cover. They are built-up, agricultural land, forest, wasteland, water bodies, grassland or grazing land and others. Through the prepared map, it has been noticed that the westernmost part and eastern most part are covered with forest. The built up, agricultural land, wasteland, water bodies majority lies in the central part of the study area which is mainly the valley portion. Several water bodies such as streams, rivers are also found to be present in the forest land. Statistical calculation show that % of land has been classed as land in use whereas 0.71% are categorized as wasteland as per the usage of land retrieve from the map which has estimated the habitat extend, loss and gains of land. This scenario revealed that not much land is been exploiting or wasted. However the wastelands need to be considered and the best possible solutions can be implemented in order that maximum usage can be guaranteed. It is anticipated that this limited information will be used for conservation or management of land planning issues and can also be used for landslide studies as anthropogenic causes. Keywords: Land use Land cover, Geoinformatics, mapping 1. Introduction Land is considered as a property and a very useful non- renewable resource available to mankind which once misused can never retain the original form. Land use usually refers to the land penetrated by the activities of man due to urbanization and how land is used by man such as agricultural land, built-up etc. and land cover refers to what covers the surface of the Earth such as water, forest, snow covered, grassland etc. In order to categorize and plan properly, mapping of land use land cover is one of the necessary methods for land evaluation, utilization, planning and management which reflects its need and great significance in the present day world. With the advancement and dynamic change of the world, the land use land cover has also changed rapidly. Therefore, the existing ones need to be replaced and upgraded to bring out the most reliable material. With the study of land usage and its pattern, the cause and its effect on the environment as well as mankind needs to be looked into through scientific studies which is one the important criteria why land use land cover map has been prepared and studied. Land use land cover has been mapped from various sources such as soil survey organizations, topographical maps, statistical data etc.; however, these are useful for specific purposes only and therefore not very reliable. However, with the advent of remote sensing technology, all these shatter problems have been wiped out overcoming all the limitations Submitted on May 2016 published on August

2 faced in the past. This leads to quick and truthful representation of the real world in the best possible manner. Over the years, remote sensing has been used for land use/ land cover mapping of parts of India and across the globe because of its benefits and accuracy. Many studies on land use land cover mapping have been done (Hoolbrook et.al., 1993) (Vimla Singh, 2012) (Jatisankar Bandyopadhyay, 2014) (Wawale Surindar G and Aher Aankush B., 2015) (Ravindra Prawasi et. al., 2015). With this background, the present study is an attempt to understand the land use and land cover mapping using remotely sensed data and associated software GIS to gain knowledge about the distribution of the land patterns, usage and its causes. The effect of human-induced land use changes on slope stability have shown that in populated regions, the impact of humans on the environment contributes significantly to the initiation and reactivation of landslides (e.g., Meusburger and Alewell, 2008; Bruschi et al., 2013). Thus land use land cover map can be even use as an important function for studying landslides, planning, conservation and management of land. 2. Study area The study area is located at the Kodagu district, Western Ghat, South India. It geographically lies between North latitude 11⁰ 56 and 11⁰ 52 and East longitude 75⁰ 22 and 76⁰ 12. It occupies an area of 4,102 square kilometers (1,584 sq. mi). The study area consist of three taluks namely Somwarpet, Vijrapet and Madikeri, headquarter of the district. It is a hilly area where the highest elevation lies to 1,750 meters (5,740 ft.), Tadiandamol peak and lowest elevation up to 900 m (3,000 ft.) above sea-level. The main river in Kodagu is the Kaveri (Cauvery), which originates at Talakaveri, located on the eastern side of the Western Ghats, with its tributaries, drains the greater part of Kodagu. It is well connected by several road networks from Bangalore, Mangalore, Chikmagulur. Mysore etc. The location of the map is shown in figure Geology of the study area The Coorg Block is bound on the north by the Mercara Shear Zone and to the south by the western extension of the Moyar Shear Zone. The area is highly sheared and foliated (Chetty et.al. 2012, Santosh et.al, 2013). The area comprises of the lithounits of Archaean, Palaeoproterozoic and Cenozoic age. The lithounits include biotite gneiss, granite gneiss, garnet-sillimanite-graphite schist, garnet sillimanite kyanite gneiss of Archean age, amphibolite, charnockite and pyroxene granulite of Archean age, granite, basic intrusive (dolerite) and acid intrusive (pegmatites) of Palaeoproterozoic age, laterite of Cenozoic age (GSI, 2006; CGWB,2007). The trending of the rock in the area are NW-SE, N-S (GSI, 2000). The lithology map of the area has been shown in figure 2. The materials collected and used to prepare the above said map are the satellite images (Landsat Etm), boundary shapes, previous literatures and survey of India toposheets of 1:50,000 scale. These are the base maps which are being used to delineate the different land cover and use and finally compiled the desired map out of it. The approach for mapping is done through visual interpretation. The Land use and land cover categorization is done based on the classification scheme developed by National Remote Sensing Agency (NRSA, 1995). The methods to prepare land use land covers go step by step. First of all, acquisition of the required data, loading, merging and georeferencing has been done. Secondly unsupervised 12

3 classification and supervised classification has been done to make it more accurate. Thirdly, identification of features with the help of tone, texture, pattern, shape and association is carried out. Lastly, statistics from the classified outputs has been generated. All these compilations have been done through GIS software. With this, the land use land cover map has been prepared. The table depicting the methodology for classification of land use land cover is given in table 1 Figure 1: Location & DEM map of the Study area map Figure 2: Lithology map of the study area (GSI, 2000). 13

4 3.1 Methodology Land use land cover mapping using Geo-informatics of Kodagu District, Karnataka Table 1: Land use/land covers classification system (NRSA, 1995) Level 1 Level 2 Level 3 1 Built-up land 2 Agricultural land 3 Forest 1.1 Towns/ cities 1.2 Villages 2.1 Crop land 2.2 Fallow 2.3 Plantation 3.1 Evergreen/ Semi evergreen 3.2 Deciduous (Moist & Dry) 3.3 Scrub forest 3.4 Forest blank 3.5 Forest plantations 3.6 Mangroves 4.1 Salt-Affected land 4 Wastelands 4.2 Waterlogged land 4.3 Marshy/ Swampy land 4.4 Gullied/ Ravinous land 4.5 Land with scrubs 4.6 Land without scrubs 4.7 Sandy area (Coastal &Desertic) 4.8 Mining / Industrial Wasteland Barren Rocky / Stony 4.9 Waste/ Sheet Rock Area 5.1 River/ streams 5 Water Bodies 5.2 Canals 5.3 Lake / Reservoirs/ Tanks Others 6.1 Shifting cultivation Grassland/grazing land 6.3 Salt Pans 6.4 Snow Covered/ Glacial Area Kharif Tank irrigated Rabi Kharif + Rabi (Double cropped) Dense Open Dense Open Dense Degraded 14

5 4. Results and discussion Land cover has always been resulted naturally as well as through anthropogenic activities whereas land use has been dominated by the later activity. Figure 3. Satellite imageries of the study area. (Landsat Etm) In the present study, as seen from the methodology, the land use land cover map has been prepared through the visual interpretation of satellite images along with the SOI toposheets integrated with GIS software. The Raw data of the used satellite image has been displayed in figure 3. Through the prepared map, Lu/Lc has given rise to it major classes namely built-up, forest, agricultural land, water bodies, Grassland/ Grazing land, wasteland and others. These are then sub classified into various types. Land use land cover map for individual taluks has also been prepared and classified in the same way. The land use land cover map of the study area is shown in figure 4 and the table of the area of the major classes is also given in table 2 and the land use land cover classification of the study area has been shown in table 3. Pie chart distribution of land use land cover pattern of the study area has also been made and is displayed in figure 5. The respective land use land cover map of each Taluk (Somwarpet, Vijrapet and Madikeri) has also been shown in figure 6a, 6b and 6c respectively and the graphs showing the distribution of land use land cover area of each taluk has been prepares as shown in figure 7. The table showing land use land cover in areas of all the three taluks combined is shown in table 4. 15

6 Figure 4: Land use Land cover map of the study area. Table 2: Table showing Land use Land cover statistics in the area. Land use Land cover Area (sq. km) Agricultural land Built-up land Forest Grassland / Grazing land Others Wastelands Water Bodies The description of each classes of land use and land cover in the area has been given below. 1. Built-up: Built-up refers to the human habitations. They are also called as settlements (village or town/cities) comprising of buildings, transportation (roadways, railways) and industrial area. With the increasing population and economic issues, built-up are growing rapidly. They are mostly located in the central part of the study area and are associated with the agricultural land, water bodies and some wasteland. About km² are made up of built-up out of km² of the total area. Each of the Taluk contains built up not necessarily of the same intensity or area. 2. Agricultural land: The agricultural land is the lands that are under plantations by mankind. They are used for farming, plantations of various crops, trees, for individual as well as commercial usage. 16

7 Figure 5: Pie diagram showing the distribution of land use land cover pattern of the area. It includes Agricultural plantation, Kharif + Rabi (Double crop), Kharif Crop and fallow land. Agricultural plantation had km² area, the crop land km² and fallow lands comprises km². As stated above, they are also found along with settlements water bodies since agriculture needs water and are done by mankind km² areas have come under this category. Thus huge area has been captured under this category. All these mention types are found in all the taluks where Vijrapet taluk comprises the maximum followed by Somwarpet and Mercara. 3. Forest: Forest land comes under the land cover which comprises of trees, vegetation types where they are not much being used but are conserved. However they are also sources of timber for personal uses as well as commercial uses. The overall area of the forest is km². According to the density of forest sub classification such as evergreen/semi evergreen forest, deciduous, scrubs forest blank, forest plantation and mangroves etc. are made. 4. Wasteland: Wasteland refers to the lands which are considered useless or degraded land. These lands are being wasted due to various reasons. They may be due to terrain, lithology and climatic factor or financial constraint or due to ignorance or unavailability of resources that it needs and makes up 0.71% (28.98km ²) of the area. This class includes barren land rocky, stony waste, sheet rock area, land with scrubs, mining and industrial wasteland. However if efforts are made then they can be recycled again to a certain extend and utilized one way or the other which may not necessarily be vegetation. They are seen mostly in Mercara district as seen in the map given in figure 4 and 6a. 5. Water bodies: These are the areas where waters are found to be accumulated or flowing through the streams. The water bodies include tanks, lakes, streams, rivers which are of various sizes. Lakes, tanks are stationary accumulation of water through streams or spring etc. and are also found mostly in the central part. This can somehow reflect that the central part is valley or basin or depression. Thus they have lower elevation than the side parts of the area. The streams or rivers are the natural course of flowing water on the land along 17

8 definite channels. Sometimes they can also be artificial. Here we can see several streams where the central and the most prominent one is Kaveri River which originates from Talakaveri. There are also in the north and south part of the area. They may be perennial or non-perennial according to its sources. The area also notices a Major river (Cauvery) which lies at the equal junction of north and south. The overall area of water bodies is km2. 6. Grassland: This type of pattern comprises of about km² area. 7. Others: These are the areas which are unknown or unnamed. Altogether, they make up km² in area. Agricultural land Built-up land Forest Grassland / Grazing land Others Wastelands Water Bodies Table 3: Classification of land use land cover in detail of study area. land use land cover classification Total No of Area Total area in Sq. Km. Agricultural Plantation Kharif + Rabi (Double Crop) Kharif crop Fallow land Industrial Area Town / Cities Village Degraded Forest Evergreen /Semi-evergreen Forest Forest Plantations Moist & Dry Deciduous Forest open Moist & Dry Deciduous Forest close Scrub Forest Grass land / Grazing land Aquaculture pond Habitation with Vegetation Mixed Vegetation Tree Groves Barren Rocky / Stony Waste / Sheet Rock Area Land with scrub Mining / Industrial Wasteland Lake / Tanks Reservoir River / Stream River Island

9 Table 4: Statistics showing taluk wise area distribution of land use land cover pattern. Virajpete Mercara Somwarpete Kodagu Land use land Total Total cover No Area in No Area in Area in No of No area in classification of Sq. of Sq. Sq. Area of Sq. Area Km. Area Km. Km. Area Km. Agricultural Plantation Kharif + Rabi (Double Crop) Kharif crop Fallow land Industrial Area Town / Cities Village Degraded Forest Evergreen /Semi evergreen Forest Forest Plantations Moist & Dry Deciduous Forest open Moist & Dry Deciduous Forest close Scrub Forest Grass land / Grazing land Aquaculture pond Habitation with Vegetation Mixed Vegetation Tree Groves Barren Rocky / Stony Waste / Sheet Rock Area Land with scrub Mining / Industrial Wasteland Lake / Tanks Reservoir River / Stream River Island

10 Figure 6a: Land use Land cover pattern in Mercara Figure 6b: Land use Land cover pattern in Somwarpet 20

11 Figure 6c: Land use Land cover pattern in Virajpet 5. Conclusion Figure 7: Graph exhibiting the distribution of land use land cover in each Taluk. The observations enumerated above highlights the significance of land use land cover in the area studies.the study area comprises of 23.69sq.km area of built-up, sq.km area of agriculture, sq.km area of forest, 52.21sq.km area of water bodies, sq.km area of grassland, 28.98sq.km area of wasteland and sq.km of unknown or others. This study reveals that for the betterment of the environment and the community at large, forest preservation and conservation should be upfront at the same time utilizing wasteland by recycling it with artificial or natural vegetation (gap filling with fertile soil and transplanting) 21

12 as the first priority or setting up recreation land. Therefore prompt efforts should be taken up aimed at utilizing the degraded land in one way or the other. It is anticipated that this land use land cover map be used by planners, decision makers or any conservation and management parties for proper planning and conservation or management of land in the area. Most important it will definitely show the scenario of landslide occurrence as land usage by mankind (anthropogenic) has paves way for accelerating landslide to a great extent. Thus the road cuttings and excavations activities of man will definitely lead to landslide and hence is a very important criterion in future landslide studies in the area. 6. References 1. Bruschi V M., Bonachea J., Remondo J., Gomez-Arozamena J., Rivas V., Barbieri M., Capocchi S., Soldati M., Cendrero A., (2013), Land Management versus natural factors in land instability: some examples in Northern Spain. Environmental Management, 52(2), pp Chetty T. R. K., Mohanty D.P., Yellappa T., (2012), Mapping of Shear Zones in the Western Ghats, Southwestern part of Dharwar Craton, Journal Geological Society of India, 79, pp CGWB (2007), Ground water information booklet, Kodagu district, Karnataka, South Western region, August. 4. GSI (2006), Geology and Mineral resoures of the State of India Part-VII Karnataka and Goa, No GSI (2000), Bangalore, District Resource Map, Kodagu district, Karnataka. 6. GSI (2000), Mercara Quardrangle map, Karnataka and Kerela. 7. Holbrook J. A and Tudor G.J, (1993), the use of Remote sensing and GIS Methods for Mapping Land Cover Change in Scotland, EARSel Advances in Remote Sensing, 2,(3), pp Jatisankar Bandyopadhyayl, Ismail Mondal and Bisari Roy, (2014), Change detection of land use and land cover and identification of inter-relationship between geomorphology and land use land cover in and around Bakkhali-fraserganj and Henry island, South 24 Parganas, West Bengal, India, International Journal of Remote Sensing & Geoscience, 3(2), pp Meusburger K, Alewell C, (2008), Impacts of anthropogenic and environmental factors on the occurrence of shallow landslides in an alpine catchment, Nat Hazards Earth System Science, 8, NNRMS, (2000),. National (Natural), Resources Information System (NRIS), Node Design and Standards, National Natural Resources Management System (NNRMS), ISRO Headquaters, Bangalore. pp

13 11. NRSA, (1995), Integrated Mission for Sustainable Development Technical Guidelines, National Remote Sensing Agency, Department of Space, Government of India, Hyderabad. 12. Ravindra Prawasi, M.P. Sharma, T. P. Babu, Om Pal, Saroj, Kirti Yadav, R.S.Hooda (2015), Land Use and Land Cover Mapping and Change Detection in Jind District of Haryana Using Multi-Temporal Satellite Data, International Journal of Science Engineering and Technology Research, 4(5), pp Santosh M., Qiong-Yan Yang, Shaji E., Tsunogae T, Ram Mohan M., Satyanarayanan M., (2013), An exotic Mesoarchean microcontinent: The Coorg Block, Southern India, Gondwana Research, xxx-xxx, pp Vimla Singh, Alok Dubey, (2012), Land use Mapping using Remote Sensing and GIS Techniques in Naina-Gorma basin, part of Rewa district, M.P., India, International Journal of Emerging Technology and Advanced Engineering, 2 (11), pp Wawale Surindar G., Aher Aankush B, (2015), Land Use / Land Cover Mapping using Remote Sensing Data in Pravara River Basin, Akole, Maharashtra, India, International Research Journal of Environment Sciences, 4(9), pp