ASPECTS REGARDING THE USE OF QGIS SOFTWARE IN THE DRAWING OF FORESTS MAPS

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1 ASPECTS REGARDING THE USE OF QGIS SOFTWARE IN THE DRAWING OF FORESTS MAPS Anghel JIMON 1 Raul DENUT 1 Dan VIDREAN 1 Florinel BOJA 1 Nicusor BOJA 1* 1 Department of Engineering and Computer Science, Faculty of Economics, Computer Science and Engineering,, Liviu Rebreanu 86, , Arad, Romania Abstract This article improves the current state of forest divisions by using QGIS software to combine forests maps with databases to improve the work of forest engineer's. A GIS is a technical and organizational set of people, hardware, software, algorithms and procedures that provide processing, managing, manipulating, analyzing, modeling and visualizing spatial data to solve complex planning problems and management forest divisions. All data in a GIS has a geographical reference. A GIS is able to display the image of a data in a cartographic format. In a GIS format, two types of information are stored: topographic details and attributes. Keywords: QGIS software, forests maps, database, topographic details INTRODUCTION All data in a GIS has a geographical reference. A GIS is able to display the "image" of a data in a cartographic format. In a GIS format, two types of information are stored: topographic details and attributes. Topographic Details Represent certain "natural" details on the terrestrial surface (eg oceans, rivers, continents, etc.) or certain "man-made" details (eg roads, constructions, parcels, Attributes describe the details in a GIS, for example the attributes of the forest fund can be all the information found in the parcel description sheet. A GIS is a computerized system used to accomplish various functions based on geographical information. The components of the system are: Software for making maps; The database that stores and links the field details and attributes; Tools for the analysis, editing and manipulation of geographic data. Forests of the country, like other real estate, need to be studied in terms of geographic location, their study and representation accurately on plans and maps must be a topical concern both in the private and in the state. The actual planing of the forest areas was done expeditiously, but the methods of planning involved some well-established topo-cadastral techniques. The use of terminals, toponyms, boundary boundaries of plots and sub-plots by painting trees and using a uniform system of conventional signs is the basis of a well-organized arrangement. Current software and hardware, classical devices (total stations) but greatly enhanced with large data storage and processing capabilities, and measurement technology based on RTK (Real Time Kinematic) GPS, orthophotomaps and various captured images, and well-used space processing and well-established standards and techniques can produce impressive results. A last ground of necessity of the topography in the forestry domain whose private property is private is the identification, measurement and land delineation of the real estate that must be fulfilled at the conclusion of the guarding contract between a forest owner and a Forest District moment in which the landing is handed over by the owner to the Forest District. Positioning details of forest fund represents an important activity for the forest management having 7

2 regard to the particular features of the applicative and Studies and research of position in the forestry conditions of working in the forestry sector. fund details of the GPS system, through various Achieve appropriate end-products of current and methods have been made in autumn, winter and spring, future requirements forestry cadastre constitutes a so in the off-season of vegetation in order to eliminate priority objective for the forestry sector, in view of the the influence of the crown on a satellite signal. map currently existing, current and present practical Positioning details of forestry fund by fast static needs. method ensures outcomes involving precision Technical possibilities and logistics base currently satisfactory, having regard to the working conditions of facilitates the promotion of technologies for highprecision the land and the technical possibilities of the positioning of areas occupied by forest technology used 5. vegetation. As a result, the positioning details inside the GNSS technology allows the application of new forestry masive and the selvage is characterised by a methods of work established with some exceptions, high efficiency, in this case, this method draws the respectively the technical conditions of operation. serious attention in order to grant due attention on the For work positioning in forest fund there are a part of the technical rules in force. number of limitations caused by the existence of forest The use of known points adiacent to the area will vegetation in different phases and stages of ensure that the relatively small size of vectors with development and configuration of the land. positive impact on the time of positioning. Although the use of GNSS technology presents a Compared with the total station GPS system for number of significant advantages due to the operating removing detail in the forestry or outside it does not principles and conditions of work that you claim may require the network layout, which gives its indisputable not be used in conditions where the signal emitted by advantage. satellites is altered by different media, especially on Data processing in GPS system using the TTC is land, at the level of surface receivers 1. characterised by high flexibility and interactivity, as a A particular situation working with GNSS result may process your information on separate technology and that pertaining to the land is occupied working sessions, weekdays or unit (block), provided with vegetation forest, giving that the fact that the existence of a sufficient number of connecting folianeous system and canopy stands default points 5. representing a genuine underlying surface (at least The results obtained from the position of forestry during the season of vegetation) is a disruptive fund in the details of the GPS system through various environment for signal emitted by satellites and methods of calculation, studied and analyzed in this reached physical level natural land area 2,3,4,5,6. study, appropriate to extend the current practice 5,8,9. As a result, the use of GNSS technology features within these areas occupied by forest massif is limited. MATERIAL AND METHODS Currently there are still constructive models of GPS receivers that allow measurements to be hostile and Surface surveys are based on the measurement satellite measurements (in close proximity to buildings, and tracing of geometric elements that define the trees, etc.), benefiting from the new position Signal position of points and directions in plan and space. Prediction, making it easier for measurements in Frequently, angles, distances, level differences and less real time even when RTK differential corrections are orientations, slopes, etc. are observed. The tools and received with interruptions 7. methods of work are distinguished by precision and It is found that the positioning of points of detail efficiency, and their choice for certain works is done that is located in the areas occupied by forest according to the field, the precision with which the vegetation, with GNSS technology, fast static method work is to be done and depending on the equipment. can be performed successfully. In the last decades, the topographic equipment has The use of GPS system for positioning the dramatically diversified and perfected through the various details of the forestry fund, although it is not expansion of modern electronics and informatics devoted to such work, ensure appropriate outcomes technologies. from the viewpoints of the precision and accuracy, GPS determinations have produced major under certain conditions 5. changes in geodesy, topography and cartography. GPS Decisive for positioning in GPS system of the (Global Positioning System) is a modern technology various points inside or on the edge of the forest that uses a complex of satellites to help determine the masive vegetation season of vegetation, the structural location of any point on the Earth's surface in a single elements of stands, orography of land and access to the reference system with the help of specific devices. GSM signal. For real-time centimeter accuracy of point coordinates, GPS-GNSS RTK is need to receive 8

3 corrections from land-based stations. This is possible GPS Trimble Geo XT 2008 equipment in hand either by UHF radio from one base (this requires 2 base with a metric precizion that allows raising points of and rover devices), or they use GSM modems to detail with satisfactory precision to forestry sector. The connect to the Internet to receive RTK corrections from component parts as well as the auxiliary elements are permanent fixed stations existing in Many countries shown in Figures 2 and 3. (ROMPOS for Romania). GSM modules work with GSM internet cards from local mobile operators. The condition of the GPS-RTK measurements is that the controller software has implemented the WGS84 coordinate system transcaling algorithm in the national coordinate system of each country (in the case of Romania - Transdat - for the transition and the Stereographic Projection 1970 as a national system). Another condition is that in the area where the measurement is carried out is a GSM data signal strong enough to make the Internet connection, otherwise, for the RTK measurements, at least two devices (base and rover) and the possibility of establishing the connection UHF radio among them. The forest fund covered by the present study Fig. 2. Auxiliary Components of the Trible Geo XT belongs to His Majesty King Michael I and is part of 2008GPS 11 the Săvârşin Royal Forestry District, being located on the territory of Birchiș commune, Arad county and Margina commune, Timiş County. The S8 GNSS Stonex (fig. 1) receiver is a highprecision equipment typically used to raise the outline of the property, using equipment that can be used with higher efficiency indoors. S8 is able to receive both GPS signal frequency and satellite signals from GLONASS and GALILEO, so we have to talk about the GNSS receiver correctly. The S8 general unit includes the GNSS antenna, the GNSS module, the UHF radio, the receiving radio antenna, the GSM / GPRS modem, the Bluetooth device and the battery. S8 is fully integrated, which makes the topographer just start the device for measurements. Fig. 3.Components of Trible Geo XT 2008 GPS RESULTS AND DISCUSSIONS Fig. 1.S8 GNSS Stonex Receiver 10 By GPS measurements, the coordinates of the points used later were calculated as routing heads and orientations, the location of these points being chosen so that the measurements are possible. Precision topographic elevation of buildings with forest vegetation required for the cadastre can not only be done with GPS technology because this type of measurement can only take place in uncovered terrain or where the free horizon can be reached up to 15º without obstacles. Also, the measurement area must have GSM coverage to receive ROMPOS corrections through data transfer. In the case of the study it was necessary to use the rover base system. The base was installed in a 9

4 GSM signal area, and the transmission between the presented the X and Y coordinates of all contour points base and the rover was possible by using an external resulting from the elevations with the GPS. By joining radio. all these points through digitization, an irregular shape For exemplification, we chose a different layout of the polygons was created which represents the unit (u.a. 147A table1 and figure 4) in which we surface of this layout. Tabel 1. Coordinates of the points determined with GPS in the parcel 147 A X Y , , , , , , , , Fig. 4 Drawing edge point in parcel 147 A Between the coordinate points determined with GPS, the route was chosen according to the terrain, aiming at the reciprocity of the visibility between the two stations on the longest distances and raising the points of detail being possible from the fewest stations (Measurement errors increase Along with the number of stations used for routing). In the same way, the surface of the tours of the development units and of a plot within Forest District I Valea Mare was obtained. In an overview of the entire Forest District I Valea Mare one can observe the boundaries of the parcels and related subclasses, resulting from the GPS elevations and those obtained from the elevations with the total station (Figure 5), superimposed over an orthophotoplan. To obtain GIS maps after the plot has been completed in AutoCad, the.dwg file is exported to Qgis to link the digital map to the Forest District I Valea Mare database, which in our case is represented 10 by parcel description a to all the layout units included in this Forest District. QGIS is a user-friendly, open-source Geographic Information System (GIS) under the GNU General Public License. QGIS is an official project of the Open Geospatial Source Foundation (OSGeo). QGIS runs on Linux, Unix, Mac OSX, Windows and Android, supporting numerous vector formats, raster, databases and functionalities. In this example, all information in the description of the parcels is presented through exact code arrangements as well as in the parcel designation sheets; but in the future, all this information in order to make it more accessible to forestry staff in the deck can be decoded and rendered in graphical form. Before a database is associated (fig. 6) and after its association (fig. 7), anforest District I Valea Mare is arranged. For example, we will take the same layout unit (147 A) as well as the area of the whole Forest DistrictI Valea Mare, figure 8.

5 Fig.5 The ParcelingForest District I Valea Mare overlapped an orthophotoplan Fig.6 Parcel 147 A Fig.7 Parcel 147 A associated to a database (parcel description) 11

6 The Qgis software allows you to play areas over 9).To illustrate the usefulness of GIS maps for the classic or top-level orthophotomaps as it is forestry sector, I will continue to present some permanently connected to an on-line graphical extremely useful maps that can be obtained with the database, making access extremely fast.for example, Qgis software (Figure 8-17) Forest District I overlays overlap (Figure 8 and Figure Fig.8 Surfaceof Forest District I Valea Mare Fig.9 Surfaceof Forest District I Valea Mare overlapped an orthophotoplan 12

7 Fig.10 Surface of Forest District I Valea Mare overlapped planes with level curves Fig.11 Forestry work map of Forest District I Valea Mare 13

8 Fig.12 Forestry map of the main species (SP 1) of Forest District I Valea Mare Fig.13 Forestry map by age classes in Forest District I Valea Mare 14

9 Fig.14 Forestry map by consistency categories from Forest Distric I Valea Mare Fig.15 Forestry map by slope categories from Forest Distric I Valea Mare 15

10 Fig.16 Forestry map by minimum altitudecategories from Forest Distric I Valea Mare Fig.17 Forestry map by production classes from Forest Distric I Valea Mare 16

11 CONCLUSIONS The division of the forest fund in the form of property ownership (public and private property) with the implementation of Land Fund Laws, excessive fragmentation of properties, the establishment of the boundaries of these properties, the measurement of real estate for a precise determination of surfaces followed by rigorous representation on plans maps of the studied areas are just some of the reasons for the necessity of a topography in the forestry field. The need for topographical work in retrocessed forests is more acute because current owners can not actually own the property right. Once restituted, these areas were excessive, and more so than the application of the retrocession laws under the pressure of any kind, the lack of situations or evidence, the lack of personnel and the measuring technology at the time have led to the occurrence of multiple problematic cases in which Refers to the exact determination of ownership limits, identification of owners, etc., which results in the need to identify, measure and register a real estate in the cadastral plan and in land registry records. Topographic surveys of forest lands have a certain difficulty with other lands. This difficulty is due to the accessibility of the points of detail both from the point of view of the land and vegetation itself and of the technology and the measurements used. Measurements based on GPS technology have the advantage that they can be done in real time, high point calculation is done automatically, precision determination is high and work productivity is satisfactory. The major drawback of using this technology in the forestry field is that this device must ensure for satellite reception the reception of the satellite signal, ie the provision of horizontal freedom up to 15º without obstacles and the existence of GSM signals enabling the connection to the permanent GPS stations. Therefore, this measurement technology can be used more to destroying support points if they can be configured. REFERENCES Ádám J., Bányai L., Borza T., Busics G., Kenyeres A., Krauter A., Takács B., 2004, Müholdas helymeghatározás, Editura Müegyetemi, Ungaria; Neuner J., Onose D., Cosarca C., Turcanu R., 2002, Utilizarea rationala a metodelor de masurare bazate pe sistemele de pozitionare globala în lucrarile de cadastru, Revista de Geodezie, Cartografie si Cadastru, Lucrari prezentate la Simpozionul National Cadastru-Tehnologii moderne de determinare, înregistrare si evidenta, vol. 11, nr. 1-2, Bucuresti; Neuner J., Savulescu C., Moldoveanu C., 2002, Studiu privind posibilitatea de determinare a coordonatelor în proiectia stereografica 1970 utilizând tehnologia GPS, Revista de Geodezie, Cartografie si Cadastru, Lucrari prezentate la Simpozionul National Cadastru-Tehnologii moderne de determinare, înregistrare si evidenta, vol. 11, nr. 1-2, Bucuresti; Neuner J., 2000, Sisteme de pozitionare globala, Editura Matrix Rom, Bucuresti; Crainic Ghiţă Cristian, Damian Vasilica Laura: Positioning Opportunities of Details From the Forest Fund with GNSS of Hill-Growing Technology with the Method "Fast Static" Analele Universitatii din Oradea, Fascicula Protectia Mediului, XVII, anul 16, p , Crainic, G. C., 2011, Cercetări privind modernizarea lucrărilor topo-geodezice din sectorul forestie, Braşov. Boş, N. 1993, Topografie, Ed. Didactică şi Pedagogică, Bucureşti. Rădulescu, M.T.G., Rădulescu T.G.A.2009, Topografie inginerească, Manual pentru tehnicieni. Dragomir, P., Rus, T., Avramiuc, N., Dumitru, P., Fădur, M., Sorta, V., 2008, Aspecte privind utilizarea ROMPOS în cadastru, Bucureşti. ***Manual de utilizare Receptor S8 GNSS Stonex, Stonex ***Manual de utilizare GPS Trimble Geo XT