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When the accuracies were compared with static GNSS surveys in both coordinate components, computation showed differences in Y and X coordinates up to -0.553 and -2.511 m, respectively. Signal attenuation caused by leaves or branches of trees resulted in low accuracy. The results obtained in this study are consistent with Pirti (2008). In addition to this, Pirti et al. (2010) also obtained similar results. Pirti (2010) states that in their study the variations were about 2-5 cm in the X-Y coordinates and about 3-10 cm in the H coordinate. They indicated that there were significant differences in the horizontal and vertical coordinates at difficult points. The results derived from this study show that with an integrated survey methodology within quite short duration of the survey (approx. 15 min.), measurements with ± 10 cm can be guaranteed under similar conditions.
This paper shows that CORS-RTK (VRS) can be used for forest surveys (obtaining accuracy dm or m level), although a common obstacle, sky blockage, hinders its full effectiveness. However, this problem can be overcome if supplemented by conventional survey techniques. In this study, the CORS-RTK (VRS) required approximately 60 minutes to survey a point (K). The integrated methodology provides accurate coordinate solutions by resection computation method to obtain the coordinates of point (K). The new alternative method of surveying a point took approximately 10-15 minutes in the field. For a point (K under the forest) the horizontal plane coordinates differed up to ± 6 cm. Therefore, it appears that in difficult environments, measurements with ± 10 cm can be guaranteed in all situations by using this new alternative method.
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