Accuracy of topographical instruments and Unmanned Aerial Systems for mapping and surveying environmental projects.

For the implementation of environmental technical projects, such as the urban forest management, a key element is the topographical and cartographic mapping of the area. Topographical instruments are based on digital, aerial or satellite information’s that can be used for producing topographical maps. This research aims to highlight that UAVs in combination with low-cost survey methods, produce topographical mapping with accepted accuracy for the implementation of environmental projects, how we can survey a road network in order to produce digital topographic maps and also how the implementation of four different ways of measuring can help us to accomplish it. The methods for executing topographic projects differ in quality, accuracy, time and cost. The results of surveying with a total station, a binary satellite positioning system, a handheld satellite positioning system and an unmanned aerial system were compared based on the accuracy of the results. Estimation of measurement error combined by the time required and the cost of each instrument and associated software for data processing were estimated. The results obtained prove that low-cost methods give sufficient and acceptable accuracy; especially the Unmanned Aerial Systems, are capable of being used for the design and implementation of forest urbanization studies.