Sažetak Svrha ovog članka detaljno je pojašnjenje problematike funkcionalnog pristupa utvrđivanja dostupnosti šumske površine, odnosno jednoznačnog i ujednačenog utvrđivanja gustoće cesta i relativne otvorenosti promatrane šumske površine koja se najčešće prikazuje na razini gospodarske jedinice. Navedena dva parametra predstavljaju neizostavne čimbenike u kasnijoj fazi planiranja optimalne mreže šumskih prometnica. Kao vodič postupka otvaranja šuma poslužio je važeći Pravilnik o provedbi mjere M04 »Ulaganja u fizičku imovinu«, podmjere 4.3. »Potpora za ulaganja u infrastrukturu vezano uz razvoj, modernizaciju i prilagodbu poljoprivrede i šumarstva«, tipa operacije 4.3.3. »Ulaganje u šumsku infrastrukturu« iz Programa ruralnog razvoja Republike Hrvatske za razdoblje 2014. – 2020. (NN 106/2015, 65/2017, 77/2017 i 84/2018), koji propisuje način izrade Elaborata učinkovitosti mreže šumskih prometnica – primarne šumske prometne infrastrukture. U ovome radu prikazani su korisni alati unutar dva najzastupljenija GIS programska paketa: komercijalnog ArcGIS programa te besplatnog QGIS programa (eng. open source). Detaljno su prikazani i pojašnjeni GIS alati unutar oba programa, a koji mogu pomoći pri izradi Elaborata učinkovitosti mreže šumskih prometnica – primarne šumske prometne infrastrukture. Ovaj stručni rad sadrži korisne informacije za sve koji se bave problematikom utvrđivanja dostupnosti šumske površine, odnosno optimalnog planiranja šumskih cesta, te za utvrđivanje stvarnog stanja gustoće cesta i relativne otvorenosti šuma kojom gospodare.SummaryThe purpose of this paper is a detailed explanation of determining the accessibility of the forest area by calculating road density and the relative forest openness on the examples of two management units. The mentioned two parameters represent indispensable factors in the later phase of planning the optimal forest traffic infrastructure network. As a guide for increasing forest accessibility, a valid Bylaw on measure implementation M04 »Investments in physical assets«, by-measure 4.3 »Grant for investments in development, modernization and customization of agriculture and forestry«, operation type 4.3.3 »Investments in forest infrastructure« from the Program of Rural Development in the Republic of Croatia in the period from 2014 to 2020 (NN 106/15) (NN 106/2015, 65/2017, 77/2017 and 84/2018), which in its appendix No. 1 – Form for the Effectiveness Study of Primary Forest Road Traffic Infrastructure prescribes the preparation of the Effectiveness study of the forest road network. This paper presents valuable tools within the two most common GIS software packages: the commercial ArcGIS program and QGIS, an open-source program. The GIS tools within both programs, which are necessary for preparing the Effectiveness study of the forest road network, are presented and explained in detail. This professional paper contains valuable information for all who deal with the problem of determining the availability of forest area, i.e. the optimal planning of forest road layout, as well as for determining the actual state of road density and the relative openness of the forests
