Geospatial Democracy
Er.R.Malliga M.E. (Ph.D) HOD/Architecture Er.B.Vimala B.E. HOD/Civil Er.P.Arun Prasath B.E Lecturer/Civil Periyar Centenary Polytechnic College, Periyar Nagar, Vallam – Thanjavur-613403 Tel: 04362-266253, Fax: 04362-266317 Email: pcgpoly@sancharnet.in
Introduction Geomatics pertains to the technology of creating the character and structure of spatial and non-spatial information, their methods of acquisition, analog and digital capture, organization, classification and qualification, analysis, management, display and dissemination, as well as the infrastructure necessary for the optimal use of the information. Applications of Geomatics are mainly oriented to the real-world problems of management of natural and man-made environment and of the objects related to it. Geomatics Technology encompasses broad range of disciplines, which include
Geomatics in India In India, the overall context of Geomatics is still in its infancy, but is fast becoming a major element of the resources management and decision making sector. Much of the efforts in Geomatics and its allied fields are concentrated amongst a limited number of government agencies and a smaller number of the private sector agencies. Some of the agencies that are involved in the field Geomatics are as follows:
Development of Mapping and Surveying Methods Traditional Method Traditional survey includes the measurement of distances by tape, stadia, angles by compass, mapping by plane table survey, leveling by auto level, angle measurement by theodolite, distance measurement by EDM (Electronic Distance Measurement ) and the most recent one TS (Total station), which is a combination of theodolite and EDM. But surveys by these traditional methods are labour intensive and time consuming. With time, there has been a need of integrating these data and maps to the GIS, which is again time consuming and labour intensive. Aerial Photography This technique is relatively more accurate and quick. One can generate 1:4000 or even larger scale maps using a 1:20,000 photograph with modern digital photogrammetry techniques. However, due to security issues, in India this techniques is not that popular and is not available to everyone. Satellite Remote Sensing The recent advances in space technology have the potential of identifying the sub-meters of an object on the ground. Hence in rural mapping the high-resolutions images like IRS – PAN with the resolution of 5.8 meter is being used to identify the rural road network and update the boundary information. Similarly the launching of IKONOS data with the 1mt spatial resolution and 4mt multispectral data is widely used in mapping even a small hut in a village level. However, the high cost of the IKONOS images (US $30 per sq km, and a minimum of 49 sq km) has deters most of the users Global Positioning System(GPS) Lately GPS has become the de-facto standard in mapping. The removal of S/A and availability of low cost hand-held GPS has promoted the use of GPS for low cost mapping. The accuracy of the derived positions varies from few ‘mm’ to several meters. Manufacturers also have started innovating and coming up with miniature GPS (Satyapraksh, 2002 ). With the availability of coast guard beacons, all over the coast, the differential corrections are available to the users, all over world, for free. Another innovation is the integration of GPSs with mobile devices, like PDAs (Personal Digital Assistants). The developments in the field of data collecting devices and miniaturization of GPS receivers has led to the use of GPS and data loggers for common mapping practices for collection of data for GIS. Laser Range Finder These are devices, which tries to overcome the disadvantages, GPS has. GPS may not work in highly dense area or with more than 20-30% canopy. However, there are GPS available, which works even in more than 30% canopy. The advantages with the laser range finders and data loggers are that they are hardware and operating system independent. However, at present, they have not made their presence felt due to cost factor, but with time, they will be available at a fraction of cost to its present cost, and it will be widely used for mapping for GIS projects. Remote Sensing Remote Sensing is a method of obtaining information about an object on the Earth surface with the help of sensor which records reflected electromagnetic energy from the objects without being in contact. Various objects are thus identified with the help of variation in the reflected electromagnetic energy from them. It is a methodology used to study form a distance the physical and chemicals characteristics of objects. Human sight, smell, and hearing are examples of rudimentary forms of Remote Sensing Necessity With growing population and rising standards of living, pressure on natural resources has been increasing day by day. Therefore, it becomes necessary to manage the available resources effectively and economically. It requires periodic preparation of accurate inventories of natural resources both renewable and non-renewable. This can be achieved through remote sensing very efficiently sine it provides multispectral-multitemporal data useful for resources inventory, monitoring and their management. Scope Remote sensing is being used to collect information about agriculture, forestry, geography, archeology, weather and climate, geology, marine environment, hydrology, water resources management and assessment, engineering etc. It has vast applications is exploration of natural resources, analysis of Lardure and Land cover, information about environments, natural hazard studies such as earthquake, land slide, land subsidone flood etc. Geographic Information System Definition Geographic Information System (GIS) is defined as a system that allows the user to question and manipulate various layers of spatial data. The system is designed to answer questions and explore relationships between spatial data; spatial and non-spatial data. The data described above represents real-world entities including both spatial (georeferenced) and quantitative attributes of these entities. GIS provides the necessary set of tools required for gaining the appropriate insights into the places and processes that drive our environment and society. By combining data from a variety of different sources such as databases, satellites imageries, and data derived from any other type of sensor or human observation, and presenting it in the form of a map a GIS provides the means of finding hidden patterns and trends that would have remained undetected using conventional means of looking at data. Components of GIS The Geographic Information System consists of the following components namely:
To the splitters, the needs of GIS are so unique as to require special programming, special hard ware, special course to introduce the fundamental concepts, special training – infact, everything that we identity with the GIS professional, or the spatially Aware professional. Highway Planning through Remote Sensing and GIS An effective system of transport is essential for economic prosperity and industrial development of any country. In a vast developing country like ours, the goal of industrial development can only be achieved through and efficient transportation system, which covers every corner of the country. Such a system is to be well planned, properly located, well – constructed and properly maintained. All these require several stages of analysis and evaluation of numerous factors. Data collection and analysis of these factors to pursue the complex interaction between man, machine, environment, time developments in the computational technology the process of data collection and analysis has become faster and cheaper. Smart System to Track Movement of Vechicles A system has been developed by OTC Digital mapping services Sdn Bhd that provide ‘ Smart ‘ locations to track the movement of a vehicle with today’s advanced ICT . It has been designed with V Guard Smart recovery System which is expected to provide an added security feature for vehicles in the event of a break – in or theft .The entire system’s hardware and software was designed in Malaysia. The company, based in Penang, developed the system using the Global System for Mobile Communications (GSM) and GPS technologies. The V Guard enables users to enhance their cars’ security. Targeting the higher- end private vehicle market, the system allows signals to be sent and received via satellites through mobile phones and computers. Users will be alerted of any unauthorized activities by SMS or through notification and can locate their vehicles with OTC’S digital mapping facility. Costal Remote Sensing and Wetland Mapping It is an established fact that nations with seacoasts have thrived well. Majority of the population lives along the coastal zones because of the multivarious advantages of being there. Apart from the advantages, there are the inevitable hazards like cyclones, tornados, inundation etc., which are also encountered along the coastal zones. A nation should have adequate information on its natural resources as well as the interrelated aspects of its activities for decision- making. This includes information about the coastal resources, their extent and the condition of wetland. The coastlines of the world, over 440, 000 km in length, represent both a dynamic natural environment and an important context in which a diverse range of human activities, as well as geomorphological and biological processes, interact. Owing to the increasing pressures on coastal areas in the form of recreation, pollution and mineral extraction, the need for integrated coastal zone management (CZM) is increasingly evident. one of the prime pre-requisites of coastal zone management is information on existing wetland conditions and changes that may have occurred in these conditions through time and space, such as degradation in coastal vegetation, inundation and increase in salt affected area etc. Decision makers and planners at all levels require information on the coastal zone to formulate policy for future development plans for conservation. India has a coastline, which is approximately 7500 km long and is sinuous in character. From east to west, the coast experiences different types of seasonal encounters. Management of the Indian coast can be viewed with respect to a number of problems and perspectives. The major issues, which require immediate attention in the context of CZM in the India, have been grouped in three areas as follows.
Remote Sensing for Groundwater Mapping Groundwater targeting still remains a Herculean task in many parts of the world as the subsurface conditions are heterogeneous in hard rock areas which cover more than 70-80% of the global surface systematic groundwater exploration was taken up in Indian in the early 50’s and was initially confined to resource evaluation in the unconsolidated or semi consolidated formation, the activity got extended to the hard rock regions about 20 years later, the techniques of surveys and actual drilling. In Tamilnadu, have already utilized more than 95% of the existing surface water and hence, are concentrating on Groundwater road. But the sporadic production and utilization of groundwater is as old as the human race. There are already more than 1.1 million wells in Tamilnadu extracting about 7 m.a. Cft. of groundwater. Recently, however, scientific large-scale development of groundwater has assumed growing importance in the economic and social development of India owing to advances in technology making possible such a development as well as the increasing demand for groundwater for meeting the increased water requirement. Generally the groundwater potential is more in sedimentary areas than in crystalline areas. The techniques have been well developed for sedimentary areas, while the procedure is complex in crystalline areas. Unfortunately, more than 75% of the area in Tamilnadu is underlain by crystalline areas and the rainfall also is much less in these areas when compared to that of sedimentary areas. The groundwater utilization also in more in crystallizes areas, and water table is going down every year because of groundwater mining in certain areas. All the above factors stand in the way of clear schemes in certain crystalline areas based on rapid groundwater survey. As a result, man started putting what all the available efforts possible right from the good-old dowsing techniques to the most modern remote sensing techniques. Remote Sensing for Soil Mapping and Classification Soils are one of the important natural resources for the survival of mankind, plants and animals. There is an intimate relation between soil, water and plants. The study of relationship between soil and water is the key factor, which determines the utilization of soil as a resource. Information on soil is required for various programmes, such as agricultural development, soil conservation, and reclamation of land, watershed, and management and Land use planning. Different soil classes respond differently in visible region of electromagnetic spectrum, depending on the physical and chemical constituents such as soil color, texture, moisture content, mineral content etc. For agricultural purposes, the precise knowledge of the characteristics, extent and location of different kinds of soil is require. Soil and its irrigation play a leading role in meeting the increased food production requirements. Irrigation places special demands on conservation and management of soil and water. The basic information required for soil conservation and land management can only be obtained through a detailed soil survey inventory. Conclusion GIS began as a highly specialized application of information technology, with its own hardware devices for input and output, its own data structures, and its own algorithms for data processing. Through time more and more aspects of GIS have become mainstream, and more and more standard approaches have been adopted to replace earlier specialized ones, taking advantage of the economies of scale inherent in the mainstream. However there are many reasons for treating geographic information as special, and for educating specialists in GIS concepts, principles, and use. |