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Soljenje cest vpliva na kemijske lastnosti tal in posledično na fiziološke parametre in rast rastlin v obcestnem prostoru. Vpliv soljenja smo preučevali na območju Pokljuke (Triglavski narodni park), kjer smo izbrali vzorčna mesta, ki so ob intenzivno soljenem cestnem odseku in referenčno mesto brez tega vpliva. Meritve rasti rastlin in fizioloških parametrov smo opravili na smreki (Picea abies). V letih 2009 in 2010 smo izmerili naslednje parametre: fotokemično učinkovitost FS II, vodni potencial, transpiracijo, vsebnost klorofila a in b ter kationov (Na+, K+, Ca2+ in Mg2+) v iglicah. Na teh vzorčnih mestih smo odvzeli vzorce tal in snega. Analizirali smo kemijske parametre in sicer, električno prevodnost, vsebnost bazičnih kationov, oziroma kationsko izmenjalno kapaciteto (Ca2+, Mg2+, K+, Na+). Analize so pokazale bistveno večje vsebnosti Na+ v snegu ter v tleh v spomladanskem obdobju. Statistično značilne razlike med soljenimi in nesoljenimi rastišči so se pokazale v ksilemskem vodnem potencialu, kot tudi v biomasi poganjkov. Za vzorčno mesto V1s, kjer so tla plitvejša, smo pri večjem številu fizioloških parametrov izračunali statistično značilne razlike z referenčnim rastiščem (V6ns), saj so razmere tam za rast smreke manj ugodne, vpliv soljenja pa se zaradi manjše kapacitete tal za vodo prej odrazi. V letu 2013, po zimi, ko je bilo porabljeno največ soli, je bila prirast rastlin statistično značilno manjša na obeh soljenih lokacijah, v primerjavi z nesoljeno. Application of de-icing salt affects the chemical properties of the soil, and consequently the growth and physiology of the plants in the road-side areas. Effects of de-icing salt applied for road maintenance was studied in the area of Pokljuka (Triglav National Park), where a reference site without the impact and two sites exposed to intensive use of de-icing salt were selected. Plant growth rate and selected physiological parameters were measured on Norway spruce (Picea abies). The following parameters were measured in the years 2009 and 2010: photochemical efficiency of photosystem II (PS II), water potential, transpiration, the content of chlorophyll a and b and the cations (Na+, K+, Ca2+ and Mg2+) in the needles. In these sites, soil and snow samples were taken for further analyses, where the chemical parameters, namely, the electrical conductivity, and the cation exchange capacity (Ca2+, Mg2+, K+, Na+) were measured. Analyses showed significantly higher levels of Na+ in the snow and in the soil in the spring samples. Statistically significant differences between salted and unsalted sites were calculated in case of plant water potential, as well as in the biomass of shoots. In the site V1s, where the soil is shallower, most of physiological parameters showed statistically significant differences in comparison with the reference site (V6ns). Most probably, due to less favourable growth conditions and lower water capacity of those soils, the effects of de-icing salt are more pronounced. In the year 2013, after the winter, when the highest amount of salt was applied, the growth of plants was significantly lower at both salted sites, in comparison with the unsalted, reference site.

V diplomski nalogi je analizirano priraščanje smreke (Picea abies) glede na starost, utesnjenost krošenj in rastne razmere na območju Pokljuke in Jelovice. V ta namen je bilo postavljenih 18 ploskev. Na vsakem izmed analiziranih dreves je bil odvzet izvrtek na prsni višini (1,3 m od tal), in sicer za prirastek v zadnjih 30 letih. Petim dominantnim drevesom na vsaki ploskvi pa je bil odvzet izvrtek do stržena. Rezultati so pokazali, da med razvojnimi fazami pri debelinskem prirastku praktično ni razlik in da se tudi odrasla smreka (debeljaki) odziva na redčenje s povečanim prirastkom. Za nobeno razvojno fazo kot tudi za vse smreke strehe sestoja nismo ugotovili razlik v debelinskem prirastku pri različni utesnjenosti. Prav tako so rezultati pokazali, da tekoči volumenski prirastek sestoja upada linearno glede na sklep sestoja in da se s starostjo odzivnost temeljničnega prirastka glede na jakost konkurence celo povečuje. This undergraduate thesis analyses the increment of Norway spruce (Picea abies) depending on age, canopy density and growth conditions in the Pokljuka and Jelovica area. In order to do this we set up 18 research plots. Each of the analysed trees was bored at breast height (1.3 m from the ground) to analyse the growth in the last 30 years. Five dominant trees per plot, on the other hand, had a sample taken to the pith. The results showed that there are hardly any differences between the developmental phase regarding diameter increment and that adult spruces (mature tree stands) respond to thinning by increasing growth, as well. There were no differences in the diameter increment for varying degrees of crown density in any of the developmental phases or for the whole stand canopy population. The results also demonstrated that the current increment in the volume of the stands decreases linearly depending on the density of the tree canopy stand and that the responsiveness of the basal area increment on the degree of competition from other trees actually increases with age.

Primerjali smo različne volumenske funkcije za ocenjevanje volumnov dreves. S pomočjo sekcijskih meritev (Newtonova metoda) smo izračunali prave ocene volumnov dreves 88 posekanih smrek na Pokljuki. Te smo uporabili za izdelavo regionalnih trovhodnih volumenskih funkcij, (dvovhodnih) deblovnic in tarif. Standardna napaka ocene povprečne vrednosti volumna drevesa je najmanjša pri trovhodnih volumenskih funkcijah (5,0 %), nato pri deblovnicah (11,7 %) in največja pri tarifah (15,1 %). Zanesljivost in uporabnost izdelanih regionalnih ter drugih volumenskih funkcij smo preverili na dveh hektarskih raziskovalnih ploskvah. Ugotovili smo, da s prirejenimi nemškimi deblovnicami smrekam določimo previsoke volumne. Ker volumne iz teh deblovnic uporabljamo tudi pri določanju prirejenih tarif na Slovenskem, je s takim postopkom določen tarifni razred z vsaj za 5 % previsokimi volumni dreves. Various volume functions used for tree volume estimations were compared by the authors. Using section measurements (Newtonʼs method), they calculated the real tree volumes of 88 felled spruce trees on the Pokljuka plateau. The real tree volumes were used to form regional three-entry volume functions, (two-entry) volume tables, and tariff functions. The standard error of the average tree volume estimation is the lowest for three-entry volume functions (5.0%), then for volume tables (11.7%), and the highest for tariffs (15.1%). The reliability and applicability of the developed regional and other volume functions was verified on two one-hectare research plots. It was established that by applying the adapted German volume tables, the measured spruce volumes were too high. As the volumes measured in this manner are used when determining the adapted tariffs in Slovenia, this procedure results in a tariff class of at least 5% too high tree volumes.

Leta 2007 smo ponovno izmerili drevesa na dveh raziskovalnih ploskvah na Pokljuki, ki so jih postavili v začetku petdesetih let prejšnjega stoletja. Vsakemu drevesu smo izmerili prsni premer in ocenili razvojno težnjo, vitalnost, dolžino krošnje, poškodbe ter osutost krošenj. Na ploskvah smo izmerili tudi količino odmrlega lesa. Lesna zaloga na ploskvah je višja za 1/5 od povprečja v rastiščnogojitvenih razredih subalpinska smrekovja in smrekovja mrazišč v prisojnih legah. Na ploskvi 40 je zgradba sestoja enomernain se ni spremenila od prvega merjenja. Zgradba sestoja na ploskvi 70 se je v zadnjih petdesetih letih spremenila iz raznomerne v enomerno. Poškodbe vplivajo na vitalnost dreves. Mehanske poškodbe, osutost in dolžina krošnje močno vplivajo na debelinski prirastek. In 2007 we have repeated the measurement of trees on two research plots on Pokljuka, which were established in early fifthies of the previous century. We have measured diameters of trees and assessed their development tendency, tree vitality, crown lenght, crown defoliation and damages. On research plots we have also measured the quantity of dead wood. Growing stock on plots is 20 % higher than the average in the same forest management class in the Pokljuka forest management unit. On a research plot number 40 the composition of the stand remains uniform since the first measurement. The composition of the stand on a research plot number 70 has changed from uneven-aged to uniform. Damages on trees are effecting vitality. Damages, defoliation and crown lenght have an influence on the intensity of the diameter increment.

Leta 2007 smo ponovili meritve na dveh raziskovalnih ploskvah na Pokljuki, obeploskvi sta veliki 1 ha, v razvojni fazi starejšega debeljaka. Na podlagi podatkov o zaporednih merjenjih dreves smo ocenili razvoj gozdnih sestojev na obeh ploskvah. Izmerili smo premere in višine dreves ter ocenili njihove kakovostne znake. Lesne zaloge so visoke, na prvi ploskvi znaša 794,6 m3/ha, na drugi pa 825,7 m3/ha. Zgradba sestoja je v zadnjih petdesetih letih ostala enomerna. Na obeh ploskvah najbolj priraščajo najdebelejša drevesa, in sicer okrog 3 mm na leto. Poškodbe vplivajo na vitalnost dreves. Osutost, socialni položaj ter dolžina krošnje vplivajo na debelinski prirastek. Stopnje osutostise po slojih razlikujejo. Povprečna osutost pri jelki je 5 % manjša kot pri smreki. In 2007 we repeated the measurements on two research plots on Pokljuka plateau, both measuring 1 ha, in the timber-phase of development. Based on thedata of successive tree measurements, we assessed the forest stand development on both plots. We measured the diameters and heights of the trees and evaluated their quality features. The growing stock is high, amounting to 794,6 m3/ha on the first plot and 825,7 m3/ha on the second. During the last 50 years, the structure of the stand remained even-aged. On both plots, the trees with the largest diameter have the highest increment, namely about 3 mm per year. Damages affect the tree vitality. Defoliation, social position and crown length affect the diameter increments. The degree of defoliation varies according to layers. The average defoliation of fir is 5% lower than that of spruce.

V mesecu juniju leta 2008 smo na dveh raziskovalnih ploskvah na Pokljuki izvedli izmero dreves, da bi dopolnili analizo razvoja sestojev na ploskvah. Vsem drevesom na dveh raziskovalnih ploskvah smo izmerili premer, kakovostne znake, naključno izbranim pa tudi višino. Prva merjenja na dveh ploskvah so bila izvedena v letih 1949 in 1963. Raziskovalni ploskvi sta bili veliki 1 ha in 0,8 ha in pripadata razvojni fazi starejšega in mlajšega smrekovega debeljaka. Lesna zaloga je visoka, na prvi raziskovalni ploskvi znaša 737,8 m3/ha, na drugi pa 1028,6 m3/ha. Zgradba sestojev se v zadnjih desetletjih ni spremenila in ostaja enomerna. Osutost iglic in dolžina krošnje dreves vplivata na debelinski prirastek. Glavni nosilec prirastka so najdebelejša drevesa. Glede na sloj, ki ga drevesa zasedajo, se spreminja dolžina krošenj, stopnja osutosti in vitalnost. Na vitalnost dreves pa vplivajo tudi poškodbe debla. In June 2008 we have carried out the measurements on two research plots on Pokljuka in order to complement the analysis of the forest stand development on research plots. We have measured diameters of trees, their quality signs and on for randomly chosen trees also the height. The first measurements on these two plots were carried out in years 1949 and 1963. The size of each plot was 1 and 0,8 hectares. They belong to the older and younger spruce largetimber stand stage of development. The growing stock is on a high level: on the first research plot it amounts to 737,8 m3/ha and on the second one 823,1 m3/ha. The composition of the stands did not change in the last 50 years, it still remains even-aged and uniform forest structure. As expected the defoliation and lenght of crown have had an influence on the intensity ofthe diameter increment. The main carriers of the diameter increment are the thickest trees. The lenght of crown, the degree of defoliation and vitality differ according to social status.Vitality of trees has also been effected by the damages.