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Understanding Lidar for Resource Management
2. RESOURCES 2.1. LIDAR IN LARGE SCALE MAPPING LiDAR is extensively used for the large scale mapping projects, which in turn takes its employment from the national level planning maps and maps for the military applications, with the integrated use of space borne IFSAR technology, along with the cartography. With the advent of the LiDAR in the development of maps the new generation map development cycle is reduced i.e. much precise, user-friendly maps in a very short development and design periods are made available. The absolute accuracy of the elevation data achieved is 15 cm however a relative accuracy of less than 5 cm or below can be achieved which is dependent on operating parameters such as flight altitude etc. The elevation data is generated at 1000s of points per second, which is far greater than traditional ground survey methods. With these high sampling rates, it is possible to rapidly complete a large topographic survey and generate DTMs with a grid spacing of 1 m or less. LiDAR data using fixed-wing aircraft flying at higher altitudes which is very essential to meet accuracies required for large-scale contour mapping LiDAR data filtered to a bare-Earth DTM can be used for aerial triangulation. The orthophoto is very useful for 3-D modeling of bridges, highway ramps, etc. Because LiDAR points are collected randomly and at an angle, points may appear atop and below bridges. This causes a feature such as a bridge to appear distorted on a digital orthophoto. With proper break-line placement, obstructions are rectified and appears geographically correct and aesthetically pleasing. 2.2. FOREST MANAGEMENT LiDAR remote sensing is a breakthrough technology for forestry applications. New LiDAR data sets provide precise measurements of various forest parameters like canopy height, sub canopy topography, and the vertical distribution of intercepted surfaces between the canopy top and the ground. Other forest structural characteristics, such as aboveground biomass, are modeled or inferred from these direct measurements Ecologists and wildlife managers are using the data to assist in applying information to better characterize, model and manage habitats and associated natural resources.  Application of LiDAR in telecommunication is going to boom in the near future. Telecommunication companies rely on accurate and detailed data sets this industry needs a spatially accurate of least one meter x, y and z to ensure proper planning. Because of its flexibility, accuracy and timeliness, these industries have started acquiring LiDAR-generated building contour renderings for the accurate geo-referenced dataset. These data are being used to evaluate radio frequency, wave interference and traffic capability.  A relatively new technology, airborne LiDAR, is gaining widespread use in seismic acquisition. Applications of LiDAR products to land seismic acquisition operations include the following:
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