INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 2, No 3, 2012

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1 INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 2, No 3, 2012 Copyright 2010 All rights reserved Integrated Publishing services Research article ISSN Anthropogenic impact on Landuse/Landcover in Dudhganga Watershed of Kashmir Valley, India Department of Geography, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi , India ABSTRACT Land use and land cover is an important component in understanding the interactions of the human activities with the environment and thus it is necessary to monitor and simulate changes. In this paper an attempt has been made to study the changes in land use and land cover in Dudhganga watershed over the span of twenty years ( ). The study has been done through remote sensing approach using two time series data. The findings revealed that the study area experienced drastic change in land use / land cover during the last two decades. The study area is characterized with the decrease in agricultural area and forest and tremendous increase in settlement all due to increasing population. The study suggested that if the present trend continues it would lead to severe degradation of natural resources of the watershed. Therefore, proper land use planning for effective management strategies and policies for the rational land use is essential for a sustainable development of Dudhganga watershed. Key Words: Anthropogenic, Landuse/Landcover, Remote Sensing, GIS, Dudhganga watershed. 1. Introduction Land use and land cover (LULC) change is a major issue of global environmental change and therefore land use/ land cover mapping is essential component where in other parameters are integrated on the requirement basis to drive various developmental index for land resource management. The land cover reflects the biophysical state of the earth s surface and immediate subsurface, thus embracing the soil material, vegetation, and water (Turner et al. 1995). Land use is a more complicated term; it has been defined in terms of syndromes of human activities such as agriculture, forestry and building construction that alter land surface processes including biogeochemistry, hydrology and biodiversity. Accelerated conversion of forest land, due to rapid urbanization and other allied activities like intensive agricultural practices, over-exploitation of resources and other anthropogenic activities have resulted to changes in land-use and land cover pattern. Significant land-use/land cover changes have been reported during the last century both on spatial and temporal scale, mainly due to economic development and population growth (Mitch and Gosselink, 1993, Sarmah et al, 2011). Anthropogenic changes in land use and land cover are being increasingly recognized as a critical factors influencing global land use change (Nagendra et al, 2003). The change in any form of land use is largely related either with the external forces or the natural increase in the population of the region concerned (Bisht and Kothyari, 2001). Land use/land cover change results mainly due to population pressure which leads to intense land use without proper management practices. As population increases more and more land is used for both Submitted on February 2012 published on February

2 construction purpose and agriculture. Over population makes people move towards sensitive areas like highlands or to live near their agricultural land. In such areas land use for agricultural and settlement purposes without considering the slope and erodibility leads to severe erosion and related problems. Application of remotely sensed data made possible to study the changes in land use/land cover in less time, at low cost and with better accuracy (Kachhwaha,1985) and Geographical Information System (GIS) provided suitable platform for data analysis, update and retrieval (Chilar, 2000). Various methods have been proposed and used to detect changes in land use/ land cover using remote sensing data such as image differencing, vegetation index differencing, selective principal components analysis, direct multi-date classification, univariate image differencing, image rationing, change vector analysis and post-classification and so on (Mas, J. F, 1999; Yang, X.; Lo, C.P, 2002). Among these methods, postclassification was a common-used method for detecting land use change and also was used in various areas successfully (Singh, A, 1989). In this paper an attempt has been made to analyze land use/land cover change in Dudhganga watershed due to human interference. 2. Study area Dudhganga catchment of Kashmir valley (Figure 1), located in the northern part of India between to N and to E, covers an area of 660 km 2. The area supports a varied topography exhibiting altitudinal extremes of 1610 to 4700 m above mean sea level. Figure 1: Location of the study area 893

3 The area consists of the lofty Pir-Panjal and flat-topped karewas as foothills and plains. The Pir-Panjal mountain range covers the Kashmir valley on the south and southwest, separating it from the Chenab valley and the Jammu region. The karewa formation is a unique physiographic feature of this area. These are lacustrine deposits of the Pleistocene age composed of clays, sands, and silts. The soils in the area are generally of three types, viz., loamy soil, karewa soil and poorly developed mountain soil (Raza et al, 1978). Climate of the area is temperate type with warm summers and cold winters. The mean annual temperature is 20 0 C. Average annual rainfall in the area is 669 mm and maximum precipitation occurs during March to April when westerly winds strike the northern face of the Pir-Panjal Mountains. The geology of the area is quite diverse ranging from Archean to Recent; Pir- Panjal represents rocks of a wide range in age. The commonest of the rocks present in the area are Panjal traps, karewa and alluvium. Drainage of the area is quite significant as most of the drainage flows into river Jhelum. Dudhganga is the important tributaries of river Jhelum which originates near Tatakuti Mountain. 3. Materials and Method The Survey of India (SOI 1975) topographic maps 43 K/9 and 43 K/13 with a scale of 1:50,000 of the area were first scanned and then registered using Erdas Imagine software. The study involved detecting changes in the LULC for which, multi-date satellite images were used that included two sets of Landsat-TM images dated 24 Oct 1991 and 29 Oct The different steps involved are: 3.1 Image Registration An important step before the generation of the land use/land cover maps happens to be the registration of the satellite images with respect to the map coordinates. Therefore, image to image registration of the two selected images was carried with the help of base map coordinates. 3.2 Image Enhancement The raw images lack image contrast that makes the feature identification difficult. These images, therefore, require enhancement using one or a combination of more then one methods of enhancement. The linear contrast stretching and band to band ratioing enhancement were applied to the images for increasing the interpretability. 3.3 Image classification The digital image classification helped in the identifying, delineating and mapping of the land use/land cover into a number of classes. The classes identified include Build up, Agricultural land, Wasteland, Forest, Plantation, Pasture land, Water bodies, Marshy land, Scrub land, Snow and Boulder bed. The image classification was performed using maximum likelihood classifier decision rule of supervisor classification method. 3.4 Land use/ Land cover change detection Land use/ Land cover changes were determined using post classification change detection method and the land use/ land cover statistics derived from data sets Landsat TM (1991) and Landsat TM (2010) was computed and compared for quantification of change. 894

4 4. Results and discussion 4.1 Land use and land cover change The Dudhganga watershed was classified using supervised classification technique into 11 Landuse/Landcover classes. The composition and distribution of land use/land cover types of images included (1) built up (2) wasteland (3) plantation (4) agriculture land (5) pasture land (6) scrubland (7) marshy land (8) forest land (9) boulder bed (10) snow and (11) water bodies. Land use/land cover maps show the spatial and temporal variation in the area. The findings reveal that there was a drastic and rapid increase in built up area and decrease in agricultural land and forest area. There have quantitative changes in the upper part of Dudhganga watershed where the reckless cutting of forest has been done for wood required in housing and furniture as a consequence of urbanization in lower regions. The inner change of land use is reflected by comparing the statistics of spatial data with that of quantitative change. The analysis of spatial change indicates that the expansion of urban settlement is taking place at the cost of prime agricultural land in the study area. The area under agriculture has decreased from 23.5 per cent in 1991 to 18.5 per cent in 2010, thus registering a decrease of 20 per cent (Figure 2 and Table 1). The study further indicates that built up area has increased from 3.74 per cent in 1991 to 11.4 per cent in 2010 registering an increase of 205 per cent and indicating the land conversion and pressure on natural resources of the watershed.. In span of 20 years the percentage of plantation area has increased from 17.8 per cent in 1991 to 19.4 per cent in 2010 and thus accounting for nearly 9 percent increase. With the increase in population, marshy land, wasteland and water bodies have been transformed into built up area particularly in the lower reaches of Dudhganga Watershed. One of the striking findings of the study is that the area under scrub land has decreased from percent in 1991 to per cent in 2010 and thus, experiences a decrease of 22 percent. Similar trend was observed in the case of boulder bed, forest cover and waste land. The area under boulder bed, forest and wasteland has declined by 27 percent, 10 percent and 11 per cent respectively. The result has been a rapid rise in population. Environmental degradation and migration have been the obvious consequences. Table 1: Land use/land cover change in Dudhganga watershed Classes Area in 1991 (Hectares) Percentage Area in 2010 (Hectares) Percentage Change Detection in (Hectares) Built up Agriculture Pasture Boulder bed Water Marshy Land Scrubland Forest Plantation Wasteland Snow Source: Computed by Authors Percentage Change 895

5 Figure 2: Landuse/Landcover map of Dudhganga watershed 896

6 Figure 3: Land use of Dudhganga in 1991 Figure 4: Land use of Dudhganga in Driving forces Population growth has been observed as the main factor affecting land use/land cover in Dudhganga Watershed. The population is continuously increasing, especially in northern part where Srinagar city is adjacent to it. Rapid population growth from 1981 to 2011 has enormously affected the Landuse/Landcover of the study area. The total population of Dudhganga increased from in 1981 to in 2001 and thus registering a growth rate of 6.5 per cent. Table 2 reveals that the watershed has been transformed from rural to urban character. In 1981 the percentage of rural population was 64 per cent and which came down to 25.7 per cent in 2011, where as the percentage of urban population in 1981 was 35.5 per cent which goes up 74.2 per cent in In 2001, the villages namely Baghi-Mehtab, Shankerpora, Machwa, Kralpora, Dharambagh, Handalbagh, Gopalpora, Wathora, Narakara, Woocha, Humhama, Khanshaib, Badgam, Galwanpora, have attained the urban character (Census of India, 2001). As the population increased, the need of living area increased. Consequently, large agricultural fields were converted into built up area (Figure 5). On the other hand more land is required for agriculture to feed the increasing population; it is here that loss of prime agricultural land is felt here. Year Total Populatio n Table 2: Demographic characteristics of the Watershed Urban Populatio n Rural Population % of Urban Population % of Rural Population * Source: Census of India 1981, 2001 and authors estimation*. Density of Population 897

7 Figure 5: Changing character of villages to urban areas in watershed Figure 6: Changing nature of landscape due to population growth This has resulted into reckless cutting of forest and thus instability of ecosystem of the region. The study has recorded a significant increase in residential area to accommodate the city s rapidly growing population. This increase in the residential area was more pronounced in the unplanned colonies. However, some planned areas have also been developed during this time 898

8 span such as Bemina and Hyderpora. There has been rapid transformation of agricultural area into residential areas. Urban expansion of city has destroyed about 3241 hectares of fertile agricultural land between 1991and The pasture land declined significantly because of rural expansion as well as agricultural encroachment with increasing land values. The expansion of urban area is not keeping pace with the increasing population. This implies that the density of population is continuously increasing. This tremendous increase of urban population is due to large scale permanent migration of high income group of people from the adjacent districts. The present city limits can not be expanded due to presence of Zabbarwan Mountains in the east. At present delineated Srinagar area is experiencing rapid and extensive development of residences outside the city municipal boundary especially in Dudhganga watersheds in haphazard manner (Figure 5). In Dudhganga watershed urbanization as a process is relatively a recent phenomenon mostly due to immigration. Consequently, rapid change in land use is observed and the watershed is being converted into dense settlement. With the increase in demographic pressure on agricultural land, scrub land has been brought into agriculture with intensification of already existing agricultural land. Similarly, the forest of the land is also going to be converted either into settlement or agricultural land in future. 5. Conclusion To sum up, the land use/ land cover of Dudhganga watershed has undergone drastic change during as a consequence of natural increase in population, heavy influx of migration from rural to urban areas and demand for settlements. The productive agricultural land is being transformed in settlement area due to increasing demand of population. The area under forest is decreasing mainly due to demand of wood for housing and furniture. The study revealed that the high income in urban areas and low income in rural areas acted as the pull and push factors of migration to the watershed. It was also found that rich people from rural areas are migrating to the lower part of the watershed adjacent to Srinagar city to fulfill the aspiration of urban life. The study suggested that the settlement area should not be allowed to increase at the expense of prime agricultural land and land use policy should be strictly followed. Remote sensing and GIS can be potential tools for monitoring the further degradation of natural resources of the watershed and for aiding land use policy options. However, nothing can be achieved unless and until we check the population growth. 6. References 1. Bisht B.S and Kothyari B.P., (2001), Land cover change analysis of Garur Ganga Watershed using GIS/ remote sensing technique, Indian Journal of Remote Sensing, 29(3), pp Chilar J., (2000), Land cover mapping of large areas from satellites: status and research priorities, International Journal of Remote Sensing, 21(67), pp Kachhwala T.S, (1985), Temporal monitoring of forest land for change detection and forest cover mapping through satellite remote sensing, Proceedings of the 6th Asian Conference on Remote Sensing, Hyderabad, pp Mas J.F., (1999), Monitoring land cover changes: a comparison of change detection techniques, International Journal of Remote Sensing, 20(1), pp

9 5. Mitch Gosselink., (1993), Landscape ecological planning through a multi-scale characterization of pattern: studies in Western Ghats, South India, Environment monitoring Assessment, pp Nagendra H, Southworth J, Tucker C., (2003), Accessibility as a determinant of landscape transformation in Western Honduras: linking pattern and process, Landscape Ecology, 18, pp Raza M, Ahmad A, Mohammad A., (1978), The valley of Kashmir: a geographical interpretation. Vikas Publishing House, Pvt. Ltd, New Delhi. 8. Sarmah P.K, Mipun B.S, Basumatary A.K, Talukdar B.K and Prasad S., (2011), Land cover change dynamics and future implication analysis in Rajiv Gandhi Orang National Park of Assam, using multi-temporal satellite data. Geospatial World Forum, Hyderabad, India, pp Singh A., (1989), Digital change detection technique using remote sensed data, International Journal of Remote Sensing, 4, pp Turner T. J, George I.M., Snowden S.L, Yusaf R and Hasinger G., (1995), Calibration corrections applied to individual PSPC events, MPE/OGIP Calibration memo CAL/ROS/95-010, NASA, Goddard Space Flight Center, Greenbelt, MD Yang X. and Lo C.P., (2002), Using a time series of satellite imagery to detect land use and land cover changes in the Atlanta, Georgia Metropolitan Area, International Journal of Remote Sensing, 23, pp