Tag: GIS

Recent Articles-IJGGS

An improved aggregation tool in GIS for hydrologic models with uniform resolution

Author(s)– Kambhammettu BVN.P et.al.,

ABSTRACT
The conventional aggregation tool in geographic information system (GIS) assumes that the aggregated grid resolution to be an integer multiple of the input grid resolution. This assumption is not always practicable, particularly in hydrologic applications, where the model resolution is decided based on number of other factors. A new tool in GIS (modified aggregation tool) is developed in the present study to generate the surface elevations and/or its derived parameters at any desired resolution. Applicability of the presented tool is tested for the Rincon Valley region in southern New Mexico, U.S.A. The 90 m digital elevation model (DEM) of the study area is aggregated and then smoothened to a uniform resolution of 402.3 m for use with the groundwater modelers and managers of the region. Surface elevations derived at model resolution using both conventional and modified aggregation tools are evaluated statistically. Results of the analysis conclude that the elevation data derived from the modified aggregation tool has resulted in minimal loss of spatial information content. The modified aggregation tool is developed such that the output dataset can be readily used by the hydrologists with no processing to the input DEM.

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Recent Articles-IJGGS

Integration of Remote Sensing data and GIS for prediction of land cover map

Author(s)– Samereh Falahatka et.al.,

ABSTRACT
Satellite remote sensing and geographic information system (GIS) have been widely applied in identifying and analyzing land use and land cover change. In this study, aerial photos and MSS, TM and ETM+ images of Isfahan and its environs were used to provide maps of land cover for 1955, 1972, 1990 and 2001. A hybrid method was used for image classification: a combination of supervised and unsupervised classification. Cellular automata filter facilities and Markov model were used together in a CA-Markov model for predicting land cover maps. To study the accuracy of the predicted maps and validation of the CA-Markov model, three methods were used: a calculating agreement and disagreement table, a chi-squared goodness-of-fit test and an error matrix. The results indicate that if land cover change processes are constant, the CA Markov model predicts land cover changes for the following years, for which agreement between predicted maps with actual map is less than 70% in this study area.

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Recent Articles-IJGGS

Land use and Land cover change detection through Remote Sensing & GIS Technology: Case study of Pathankot and Dhar Kalan Tehsils, Punjab

Author(s)– Prabhbir Singh, Kamlesh Khanduri

ABSTRACT
The objective of study is to prepare land use/land cover map for different time periods, analyse the land use changes and evaluate the socio – economic implications of predicted change. Landuse changes have been detected by image processing method in EDRAS imagine9.3, ArcGIS9.3. Monitoring of landuse/landcover changes help to plan development activities such as major schemes and for community requirements. Fifteen year time period of 1991 -2006 shows some major land use changes.  During this period of fifteen years 104.02 sqkm areas has undergone positive changes into Cropped Land and Builtup areas from Forest and Fallow land.  There is a remarkable increase (69.23sq/km) in the area of Crop Land.

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Recent Articles-IJGGS

Time sequential surface change analysis of Talcher-Angul region of Orissa using Remote Sensing  and GIS

Author(s)– Shweta Panwar, Rakesh Kumar Sinha, Gurdeep Singh

ABSTRACT
Angul-Talcher has been emerging as a major industrial centre with intense and large scale coal mining activities. As a consequence, this has been declared as a critically polluted area particularly due to severe land degradation. Land use pattern of Angul Talcher has undergone several changes over the years. Surface and sub surface mining and industrial activities have resulted in considerable changes in the land use pattern. An attempt has been made to study the time series surface changes in Land Use and Land Cover in Talcher-Angul region for the years 1973, 2007 and 2011 covering an area of 5028 sq.kms. Different interpretation techniques such as unsupervised classification, digitization and visual interpretation were used on the satellite image, toposheet and Google Earth image respectively. An immense increment of 22.58% can be seen in wasteland and decrement of 26.44 % in agriculture over a period of 38 years. During 1973 and 2007, major changes took place in wasteland and agriculture however between 2007 and 2011, the forest was the most affected entity with a decrease of 1.4%. This study emphasises the need to hold the agricultural lands and forests from the growing mining and industrial interference.

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Recent Articles-IJES

Groundwater quality and its suitability to agriculture – GIS based case study of Chhatna block, Bankura district, West Bengal, India
Author(s)- Nag.S.K, Poulomi Ghosh

ABSTRACT

Water pollution is a major challenge amongst all other types of pollution. A number of factors like geology, soil, effluents, sewage disposal and other environmental conditions in which the water happens to stay or move and interact are responsible for this. The study has been made to find out the status of groundwater quality and its suitability in regards to irrigation purpose. A total number of 23 water samples from borewells have been collected for pre-monsoon 2009 and post-monsoon 2009 from Chhatna block, Bankura district, West Bengal, India. Water quality data used in the present study include Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Hardness (TH), Soluble Sodium Percentage (SSP), Residual Sodium Bi-carbonate (RSBC/RSC) and Sodium Adsorption Ratio (SAR). From the results of analysis, it is revealed that the values of Sodium Adsorption Ratio indicate that, ground water of the area falls under the category of low sodium hazard. So, there is neither salinity nor toxicity problem of irrigation water, and hence the ground water can safely be used for long-term irrigation.

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Recent Articles-IJGGS

Stream dynamics change analysis using Remote Sensing and GIS techniques

Author(s)– Suryavanshi Shakti et.al.,

ABSTRACT
In the present investigation, an effort has been made to study the stream dynamics of the Chambal River using Remote Sensing and Geographical Information System techniques. To determine the changes in flow dynamics, meandering and Entrenchment Ratio (ER) of the Chambal river satellite data of MSS (1972), TM (1990) and ETM+ (2000) has been used. In this study, the bankfull width of the river was obtained by digitizing the MSS, TM and ETM+ satellite imaginaries. The central flow lines of the river in all three years were digitized and compared to find out flow dynamics, meandering and Entrenchment Ratio (ER). The origin of the river was considered from the Rana Pratap Sagar dam. The river dynamics changes at forest land, ravineous land and the places where it joins river Yamuna. The river Chambal has been found to be meander continuously towards the right during past 28 years at a distance of 140 km away from the origin. The maximum and minimum width of the river Chambal was found to be 1698 and 227.23 m at a distance of 300 and 150 km respectively. The maximum ER was found to be 3.5 at a distance of 350 km away from the origin. The study revealed that RS and GIS techniques are useful to find out the stream dynamics of the river.

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Recent Articles-IJGGS

Micro watershed characterization and prioritization using Geomatics technology for natural resources management

Author(s)– Binay Kumar, Uday Kumar

ABSTRACT
Management of watershed encompasses various activities from watershed delineation to monitoring. The suitability of land for development is not only based on a set of physical parameters (geography/terrain, soils, slopes, forest, geology etc.) of the land but also very much on the economic factors. The cumulative effect of these factors determine the degree of suitability and also helps in further categorization of land into different priority orders for development. Sanjai river watershed is located in the central west part of the Subernarekha basin under Kolhan Division of Jharkhand. The study area is totally rain-fed and availability of water for drinking and domestic use is a big problem. The natural recharge process in the area is very poor due to hard compact granite terrain. The response of a watershed to different hydrological processes and its behaviour depends upon various physiographic, hydrogeological and geomorphological parameters. The characterization of a watershed provides an idea about its behaviour. The various parameter characteristics of a watershed behave in more or less perceptible manner. Watershed prioritization is the ranking of different micro-watersheds of a watershed according to the order in which they have to be taken up for development.  Holistic integrated planning, involving remote sensing and GIS has been found to be effective in planning for regional development based on watershed approach. Saaty’s analytic hierarchy process is a most widely accepted method for scaling the weights of parameters by constructing a pair wise comparison matrix of parameters where entries indicate the strength with which one element dominates over another vis-à-vis the relative criterion. The pair-wise comparison of parameters results into the “importance matrix” which is based on a scale of importance intensities A Composite Suitability Index (CSI) has been calculated for each composite unit by multiplying weightages with rank of each parameter and summing up the values of all the parameters. Categorization of the CSI is achieved by ranging the CSI into classes, where each range indicates the amount of limitation acceptable for each class.

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