INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 2, No 4, 2012

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1 INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 2, No 4, 2012 Copyright 2010 All rights reserved Integrated Publishing services Research article ISSN Monitoring of urban Land Use/Land cover (LULC) changes in parts of greater Visakhapatnam municipal corporation (GVMC) and surrounding areas, A.P Using Remote Sensing and GIS Techniques Anil N.C 1, Jagannadha Rao.M 2, Jai Sankar.G 1, Greeshma Gireesh.A.G 1, Sailaja.U 2, Shravan Kumar.A 1 1- Department of Geo-Engineering, Andhra University, Visakhapatnam. 2- Delta Studies Institute, Andhra University, Visakhapatnam nathianil@gmail.com ABSTRACT Urban areas are changing due to various human activities, natural conditions and developmental activities. According to the user requirements, updating of land use maps are required to various departments and hence information of land use/land cover in the form of maps and statistical data are very vital for spatial planning, management and proper utilization of land. In this paper an attempt is made to study the changes of land use and land cover between two data sets with a span of 12 years of Greater Visakhapatnam Municipal Corporation (GVMC) and surroundings areas. The study has been done through Remote Sensing and GIS approach using SOI topo sheets, and IRS LISS-III 1998, IRS LISS-III 2010 satellite data. The present study has brought to light that the land use/land cover classes like built-up land has increased from 15.38% to 27.71% during with a net increase of 12.33%, industrial area has increased from 6.48% to 8.32% with a net increase of 1.84% during the years and also area under plantations has increased from 10.42% to 10.87% during with a net increase of 0.45%. But some classes like forest area have decreased from 27.95% to 18.34% with a net decrease of 9.61% during the years And it was found that harbour area has remained unchanged during which can be considered as a positive trend. The reasons for this increase and decrease have been discussed. Another important outcome of this study is the trend of illegal construction activity on the hill slopes of the study area. This aspect is taken up as on a priority bases in this study. The results indicate that during the study period ( ). The hill slope occupation has been increased significantly from 1.88% (11.72sq.km) to 5.57% (34.65sq.km) indicating enormous rate at which the hill slopes are being occupied. This is an alarming indication for the GVMC to take immediate and necessary steps. So in order to monitor the land use/land cover pattern, proper land use planning is essential for a sustainable development. This is especially needed for the situation of hill slope occupation, otherwise this will have severe environmental impacts on natural drainage, slope vegetation, groundwater recharge besides resulting slope collapse. However the land use/land cover data of other classes during the study period ( ) indicated certain changes which may not indicate significant environmental impact, however these trends need to be closely monitored for any complications that may arise in future, especially with regard to hill slope occupation. Keywords: Land use/land cover, Change Analysis, Remote Sensing techniques. 1. Introduction Land use change is the modification in the purpose and usage of the land, which is not necessarily only the change in land cover but also changes in intensity and management Submitted on March 2012 published on May

2 (Verburg, et al, 2000). The land use/land cover pattern of a region is an outcome of natural and socio economic factors and their utilization by man in time and space. Information about land use change is necessary to update land cover maps and for effective management and planning of the resources for sustainable development (Alphan 2003). Urban land cover types and their areal distribution are fundamental data required for a wide range of studies in the physical and social sciences, as well as by municipalities for land planning purpose (Stefanov, 2001). Over the years, remote sensing has been used for land use/land cover mapping in different parts of India (Gautam and Narayanan, 1983: Sharma et al., 1984: Jain, 1992; Brahabhatt et al., 2000). Accurate and up-to-date land cover change information is necessary to understand and to assess the environmental consequences of such changes (Giri et al, 2005). Remote Sensing and Geographic Information System (GIS) have been combined to detect and control urban encroachments in a way which is easier and faster than the traditional methods of surveying the urban environment (Da Costa, 1999). The present study has been taken up in order to understand the changes that have taken place in land use/land cover of Greater Visakhapatnam Municipal Corporation (GVMC) and surrounding areas. The rapid industrialization and urbanization of Visakhapatnam the present study area (GVMC) resulted increased migration of people from surrounding rural areas and causing serious competition for residential zones. In recent times the city is facing the problem of unauthorized occupation of all available hill slopes in Visakhapatnam urban and industrial areas, some of the slopes occupied are at Hunumantuvaka, Venkojipalem, Seetamadhara, Tatichetalpalem, Kailasapuram, Kancharalapalem, Endada, Pottnamallayyapalem, Marripalem, Madhavadhara, Aganampudi, Kannuru, Jonnala, Yarada etc. In this study this aspect is also given priority and within 12 years period the trend of slope occupation is brought out. It is believed that this aggressive human activity might have influenced on the land use/land cover patterns resulting possible impact on the environment. With this background this work is taken up. 2. Study Area The study area is located in and around of Greater Visakhapatnam Municipal Corporation, Andhra Pradesh. The area covered in this investigation is about sq.km, Visakhapatnam District is one of the North Coastal districts of Andhra Pradesh and it lies between ' and ' N latitude and ' and ' E longitude (Fig: 1). It is bounded on North side partly by Orissa state and partly by Vizianagram district, towards South by East Godavari district, towards West by Orissa state and towards East by Bay of Bengal. 3. Objectives The aim of this study is to produce a land use/land cover map of Greater Visakhapatnam Municipal Co-operation and surrounding areas in order to detect the changes that have taken place and to find out the hill slopes occupied particularly in the same over a given period using the method of change detection. This work has been undertaken with the following specific objectives. 1. To create a land use / land cover classification scheme. 2. To determine the trend, nature, rate, location and magnitude of land use / land cover change during the study period. 3. To understand the pattern of illegal occupation of slopes. 965

3 4. Data Used Figure 1: Location map of the study area For monitoring the land changes in land use/land cover, LISS-III digital data of 10 th May 1998 and LISS-III digital data of 22 nd March 2010 have been used. The Survey of India (SOI) topographical maps of the series 65-O/1, 65-0/2&3, 65-0/5, 65-0/6 at the scale 1:50000 were used along with other collateral data. 4.1 Methodology & Data Processing The studies of monitoring urban land use/land cover were identified with the help of topographic map prepared in 1977 and compared this topographic map with satellite images. For the purpose of study of land use/land cover ARC GIS 9.2 and ERDAS IMAGINE 9.1 have been used. 966

4 Figure 3: Pictorial representation of areas occupied by LULC during The different LU/LC classes that have been identified are airport, built-up land, commercial area, forest areas, harbor, industrial area, plantations, water bodies, beach sand, salt pans, fallow lands, scrub lands, recreational areas, degraded forest etc, for both the data sets by using standard classification methodology which is in vogue. Later Change Detection methodology was done for both the images to find out the changes that have taken place in the study area by using ERDAS IMAGINE 9.1. The feature classes were identified based on the visual interpretation of the satellite imagery coupled with filed checks. These datasets were digitized and analyzed to obtain land use/land cover statistics for the areas under each of these categories for both the years. An attempt is made to study the trend of hill slope occupation for residential construction. To understand this trend the area of hill slope occupation during 1998 and during 2010 has been computed by fixing the polygons and there by the area is determined on different hill slopes using GIS software. The increase in the area under slope occupation between has been brought out. Pre processing is done by scanning and digitization of Survey of India Toposheets at 1:50,000 scale to serve as the base map, later geo-referencing has been undertaken. Processing is involved applications of various GIS techniques and advanced digital image processing techniques including manipulation, edge enhancement, and image registered. The images were geometrically rectified and registered to the same projection in order to lay them over each other. Later 967

5 these imageries were classified to find out different land use/land cover categories for the data sets. 5. Results and Discussion Figure 2: Land use/ Land cover during the study period After Geo-referencing the satellite data were processed in ARC GIS 9.2 and by visual interpretation the classes were identified and they were ditiziged as shape files to produce a detailed land use/land cover map for both the digital data sets of the study area (Fig: 2) and also attribute information is obtained (Table. 1), i.e. the area and percentage occupied by different classes for both the data sets of the study area. Based on this the changes that have taken place between the two data sets have been brought out and presented in pictorial representation (Fig: 3).The different LU/LC categories that have been identified are airport, built-up land, forest areas, harbor, industrial area, plantations, water bodies, beach sand, salt pans, fallow lands, scrub lands, recreational areas, and water logged area, for both the data 968

6 sets by using standard classification methodology which is in vogue. The details have been discussed below. Table 1: Attribute data of Supervised Classification Sl.No Feature Class Area Occupied (sq.km) % Of Area area Occupied Occupied (sq.km) % Of area Occupied Net Change 1. Airport Beach sand Built up land Fallow land Forest area Harbour Industrial area Plantation Recreational area Salt pans Scrub land Water body Water logged area Total area The attribute data of land use/land cover from the study area between years 1998 and year 2010 with regard to various features indicated significant changes in feature classes(figure 4). The data indicates that the airport area has increased from 1.09% in the year 1998 to 1.2% in 2010 with a net increase of 0.11%. The reason is due to increased air traffic caused the expansion of Airport and its facilities, resulted this increase. It is to be noted that the location of the airport and its facilities are situated in the marshy area, which is environmentally a sensitive zone. In fact the obstruction of natural drainage by the airport construction caused severe drainage problems earlier. Such problems may be repeated again. The area under beach sand has decreased from 0.44% in the year 1998 to 0.41% in the year 2010 with a net decrease of 0.03%. This can be attributed to be due to two reasons, because of natural beach erosion and other one is due to occupation of beaches for construction activity. Earlier study (Rao and Naidu, 1989) indicated that the beach erosion in this part of the coast is due to the construction of outer harbour, which has caused the disturbances of natural erosion and accretion cycle of sand deposition in the beach. The area under built-up land has shown an increase from 15.38% in the year 1998 to 27.71% in the year 2010 with a net increase of 12.33%. This is the natural consequence of increased urbanization and resulted construction activity in terms of residential areas, commercial establishments including educational institutions, hospitals, storage facilities etc at the places 969

7 like R.T.C.Complex, Dwarakanagar, Akayyapalem, NAD, Gajuwaka, Seetammadhara, Seetammapeta, Isakotota, Maddipalem, M.V.P.Colony, Kancharapalem, Gopalapatnam, Kommadi, Narva, P.M.Palem etc. The area under forest cover has decreased from 27.95% in the year 1998 to 18.34% in the year 2010 with a net decrease of 9.61%. The reason for this is because of rapid industrialization and urbanization. The ecosystem is being disturbed and as a results the forest area is being decreased and also due to urbanization the people are cutting the forest cover and occupying these areas to meet their residential requirements. The feature class under harbor area has shown no change during the study period. However it is observed that within the harbor area considerably surface destruction and pollution is clearly shown on an increasing trend. This is because of the fact the moment of heavy vehicular traffic carrying commodities like iron ore, sulphur and other chemicals, the entire area is physically changed from the original land scape. This need to be considered and proper action may be taken to re-establish the original landscape of the area. The area under industrial area has increased from 6.48% in the year 1998 to 8.32% in the year 2010 with a net increase of 1.84% this shows a considerable increase in industrialization, however the effects of the industrialization on the environment need to be continuously monitored to establish the possible damage if any. The area under plantation has increased from 10.42% in the year 1998 to 10.87% in the year 2010 with a net increase of 0.45%. The reason for this increase is because of the increased awareness on the environment among the people as well as among the local authorities including industries. This resulted the continuous plantation in various parts of the city. Industries like Visakhapatnam Steel Plant have taken a policy to maintain its premises with forest cover on par with, the recommended environmental requirements. A number of private and non-governmental organizations are also involved in active plantation of trees. This is one of the positive signs. The class under recreational area has increased from 1.63% in the year 1998 to 1.75% in the year 2010 with a net increase of 0.12%. The reason for this increase may be due to the development of parks, sites for recreation, places of leisure etc by GVMC as well as by Visakhapatnam Urban Development Authority (VUDA) and some private agencies. This is in responses to the demand from people who or more keen to enjoy during weekends and holidays, and prefer to spend their time outdoors. The area under salt pans have decreased from 2.68% in the year 1998 to 2.11% in the year 2010 with a net decrease of 0.57%.The reason for this decrease can be due to the conversion of salt pans area into various small and medium scale industries which are being established at a rapid pace in the study area. The area under scrub land has decreased from 19.60% in the year 1998 to 17.76% in the year 2010 with a net decrease of 1.84%, the reason for this is due to rapid industrialization and urbanization the people of GVMC are forced to occupy the scrub lands resulting the decrease of these areas. The feature class under water bodies has decreased from 1.49% in the year 1998 to 1.31% in the year 2010 with a net decrease of 0.18% which is considered as a negative trend. The reason for this can be attributed to the enormous increase of the cost of the land because of which the water bodies have been illegally occupied and converted into residential plots etc. 970

8 This trend is very commonly seen in different parts of the study area, which is a dangerous trend. The area under water logged area which is not found during the year 1998 but where as in the year 2010 it was found occupying 3.60% in the year This is because of the fact that the natural drainage network of the study area like natural drains, streams, water channels etc have been either occupied or destroyed, because of the industrial and urban construction activity resulting the rain water to stagnate in low laying areas. This is one of the serious environmental impacts observed in the study area in recent times. In fact the Airport had to be closed for considerable period recently due flooding, this aspect need to be monitored closely. Figure 4: Percentage distribution of LULC during years Detailed Study on Slopes The study area is facing one of the significant and alarming situations by the way of illegal construction activity on the slopes of the hilly regions in the areas like Hunuamantuvaka, Mudhravada, Kailas hill, Gajuwaka, etc. This is a complex problem of social and political implications, where by homeless people are forcibly occupying hill slopes and making constructions like huts, thatched houses, concrete slabed houses etc. This is causing the destructions of natural slope morphology including natural drainage, soil cover, slope vegetation and slope stability. A number of incidents have occurred resulting slope collapse causing fatal accidents and loss of human lives. In this investigation an attempt is made to see the pattern of illegal constructions on hill slopes, for this purpose output maps have been prepared showing the occupation along the hill slopes during the year It is very clear that in the year 1998 an area of sq km was under the slope occupation, where as 971

9 in the year 2010 the occupation has increased to sq km with a net increase of 22.93% (Fig: 5) which is considered as a negative trend. The hill slope areas which were occupied during the year 1998 are at the places of Marikavalasa, Bakkanapalem, Potinamallayyapalem, Togaruvu, Mudasarlova, Hunuamantuvaka, Venkojipalem, Seetamadhara, Tatichetlapalem, Kailasapuram, Kancharalapalem, Simhachalam, Kottavuru, Navsenabagh, Gajuwaka, Gontinivanipalem, Chinna Gantiyada, Marripalem, Gonnavanipalem, Kaniti, Yarada etc and during the year 2010 hill slopes occupied at the places like Paradesipalem, Marikavalasa, Bottavanipalem, Knmmadi, Bakkanapalem, Revallapalem, Pottnamallayyapalem, Endada, Totagaruvvu, Arilova, Mudasarlova, Santapalem, Dharapalem, Adivaram, Simhachalam, Pendurti, Pulagalipalem, Purushottapuram, Venkojeipalem, Isakatota, Seetammadhara, Tatichetlapalem, Kancharapalem, Kailasapuram, Marripalem, Madavadhara, Murali Nagar, Gopalapatnam, Satyavanipalem, Talarvanipalem, Aganampudi, Kannuru, Satram, Jonnala, Yarada etc. Table: 2 gives us the details of hill slopes occupied in the study area during in square kilometers. It is to be noted that the occupation of slopes is being taken places in the new areas as well. The areas such as Madhavadhara, Seethammadhara, Murali Nagar, Gajuwaka, etc have shown increasing trend of illegal occupation of slopes. If this trend continues the GVMC and surrounding areas may face a serious threat of 100% slope occupation resulting unforeseen environmental catastrophes including depleting ground waters, flooding of roads, slope collapse, reduced slope vegetation cover and many other socio and economic problems including human loss. Hence immediate action need to be taken by the government authorities to stop further occupation of hill slopes in future. Figure 5: Slopes occupied during the year 1998 and

10 Table 3: Slopes Occupied During the period Sl.No Place Name Lat/Lon Values Slope occupied during 1998 (Sq.Km) 1. Chinna Gantyada 83 11'26.59 E /17 40'40.86 N 2. Devi konda 83 06'22.53 E /17 34'02.16 N 3. Jonnala konda 83 12'49.16 E /17 35'37.29 N 4. Kailasa konda 83 16'27.41 E /17 45'21.95 N 5. Kambala konda 83 18'26.44 E /17 46'50.92 N 6. Kannuru konda 83 62'29.96 E /17 41'48.79 N 7. Narva reserved 83 09'26.76 E forest /17 44'10.67 N 8. Aganampudi 83 07'49.60 E konda /17 41'24.61 N 9. Bottavanipalem 83 21'53.65 E Konda /17 49'55.28 N 10. Marripalem Konda 83 07'15.33 E /17 42'28.77 N 11. Pata Gajuwaka 83 12'14.38 E konda /17 41'17.23 N 12. Pendurti konda 83 12'15.38 E /17 48'17.67 N 13. Porupalem konda 83 12'24.63 E /17 46'09.93 N 14. Pedda Gantyada 83 12'32.72 E konda /17 40'39.95 N 15. Pola konda 83 06'28.61 E /17 33'31.50 N 16. Simachalam konda 83 14'21.64 E /17 45'33.41 N 17. Yarada konda 83 14'58.70 E /17 39'57.96 N 5.2 Conclusions Slope occupied during 2010 (Sq.Km) Total Area (Sq.Km) The study clearly established that the satellite remote sensing coupled with tools like image processing and GIS can be a powerful tool for mapping and evaluation of land use/land cover changes of a given area. The similar study was carried out in the study area comprising of Greater Visakhapatnam Municipal Corporation and surroundings areas ( ' and ' N 973

11 latitude and ' and ' E longitude) brought out significant land use/land cover changes. Some significant observations of the changes and trends of LULC in the study area need to be monitored closely these include the occupation of natural water bodies, natural drainage which may cause water logging in certain areas. This is already causing serious problems at some of the places. The decrease in vegetation cover and forest cover may be an aspect of serious concern and the planners and policy makers need to take necessary steps for conserving forest cover. The beach and coastal erosion by man made reasons should be closely monitored and necessary scientific steps must be taken to stop to stop the beach erosion to avoid further environmental complications. The most serious threat observed in this study area during the study period is the occupation of hill slopes at an enormous phase posing serious environmental impact in the form of distruction of the natural slope morphology including natural drainage, soil cover, slope vegetation and slope stability. The possible impacts include the depletion of groundwater, water logging in low laying areas, gradual collapse of hill slopes resulting loss of human life and property. If this continuous the natural land scape which is considered as most beautiful in this city, will be lost forever. 6. References 1. Alphan, H., (2003), Land use changes and urbanization in Adana, Turkey, Land degradation and Development, 14, pp Brahabhatt, V.S., Dalwadi, G.B., Chhabra, S.B., Ray, S.S., & Dadhwal, V.K., (2000), Landuse/land cover changes mapping in Mahi canal command area, Gujarat, using multi-temporal satellite data, Journal of Indian Society of Remote Sensing, 28(4), pp Gautam, N.C., & Narayanan, L.R.A., (1983), Landsat MSS data for land use/land cover inventory and mapping: A case study of Andhra Pradesh, Journal of Indian Society of Remote Sensing, 11(3), pp Giri, C., Zhu, Z., & Reed, B., (2005), Comparative analyses of the Global land Cover 2000 and MODIS land cover data sets, Remote Sensing of Environment, 94, pp Rao, M.J., & Naidu, G.B., (1989), A note on erosional tendency at the Visakhapatnam beach Environment, Indian journal of environmental protection, 9(11), pp Sharma, K.R., Jain, S.C., & Garg, R.K, (1984), Monitoring land use and land cover changes using landsat imager, Journal of Indian Society of Remote Sensing,12(2), pp

12 7. Stefanov, W.L., Ramsey, M.S., Christensen, P.R., (2001), Monitoring Urban Land Cover Change: An expert system approach to Land Cover Classification of semiarid to arid urban centers, Remote Sensing of Environment, 77, pp Verburg, P.h., Chen, Y., Soepboer, W., & Veldkamp, A., (2000), GIS-based modeling of human-environment interactions for natural resources management:, Applications in Asia. In Proceedings of the 4 th International Conference on Integrating GIS and Environmental Modelling (GIS/EM4): Problems, Prospects and Research Needs, Canada 2000, Da Costa, S.M.F., Cintra J.P., (1999), Environmental Analysis of Metropolitan Areas in Brazil, ISPRS Journal of Photogrammetry & Remote Sensing, 54, pp