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ŠUMARSKI LIST 9-10/2011 str. 26 <-- 26 --> PDF |

V. Račko, M. Saniga, I. Čunderlík: THE IMPACT OF SILVICULTURALTREATMENTS ON THE STRUCTURE ...Šumarski list br. 9–10, CXXXV (2011), 437-448 The diameter of samples and the width of the DZage (CA) of the trunk were counted.The ratio of DZ to and RH were measured.At the same time, the age ofRH was calculated as ratio of DZ width or RH and diathe tree at DBH and at other heights and the cambialmeter of the trunk as a percentage. RESULTS – Resultati The analysis of theTable 1 and Table 2 points outtrees, obtained from the CMT 513, have,at partially that the DBH structure of tree samples for a differentdifferent age,higher parameters of the DBH and volusilviculture technology is different. In case of the CMTmes of the down third of a trunk. Higher parameters of 513, the DBH are statistically significantly bigger thanquantitative production are the result of a considerably CMT514 b. In CMT513, where trees of an upper levelhigher capacity of assimilation apparatus of a crown. are autonomous in growth during practically whole ob-The analysis of production parameters of beech samservation time, creates assumptions of more intensiveples confirmed, despite their partially different age,that diameter growth. Moreover, it is necessary to add toselection structure of a stand creates significantly good this fact partially the factor of age, whereas observedqualitative assumptions for its quantitative and value samples are approximately 10 years older.The sampleproduction. Table 2T-tests of mean values of tree characteristics for investigated CMTs. Tablica 2.T-test srednjih vrijednosti značajki stabala istraživanih sastojina (CMTs) CMTTree agep-valueDBHp-valueCrown lengthp-value OdjeliDob stabalap vrijednostPrsni promjerp vrijednostDuljina krošnjep vrijednost 513109.7±1.5847.9±3.6317.1±4.15 0.0001***0.0494*0.5846ns 514b97.7±3.5143.8±5.3818.3±3.18 Meanvalues(within the same column mean ± standard deviation (SD)) werecalculatedbased onmeasurementstakenin december 2009. Student´st-test(p-value – level of statistical significance, *p < 0.05, **p < 0.01, ***p < 0.001, ns - not statistically significant, p > 0.05). Srednje vrijednosti (u istoj koloni dane su srednje vrijednosti i standardna devijacija) temeljem mjerenja iz prosinca 2009. godine. Student-ov t-test (p-vrijednost – stupanj statistički značajne razlike – ns nije statistički značeno). 3 Table 3Comparisonof crownvolumes C(m) developmentduring the last23 yearsfor investigated CMTs Tablica 3.Usporedba volumena krošanja Ck k (m3) tijekom 23 godine motrenja na istraživanim plohama CMTs CMT Odjeli 19861991199720012009 C k p-value p vrijednost C k p-value p vrijednost C k p-value p vrijednost C k p-value p vrijednost C k p-value p vrijednost 513 514b 297±133 175± 69 0.0432* 391±156 197± 74 0.0328* 582±234 357±188 0.0087** 624±266 386±145 0.0432* 727±401 723±353 0.9812ns Within the same column (mean ± SD).Student´s t-test(p-value – level of statistical significance, *p < 0.05, **p < 0.01, ***p < 0.001, ns (not statistically significant, p > 0.05). U istoj koloni dane su srednje vrijednosti i standardna devijacija. Student-ov t-test (p-vrijednost – stupanj statistički značajne razlike – ns nije statistički značeno). The average crown volumes forindividualCMTs duringthe past23 yearssignificantly differed, withthe exception ofthe lastgrowthperiod2001–2009.The average crown volumes (in theyears1986–2001)inthe CMT513was about 23–35% higher,thanin theCMT 514b (Table 3). The analysis of correlation strength between tree samples DBH and their height for the whole period of observation (23years) is characterized in the Fig. 3a, 3b. While we are assessing this dependency on CMT513 (Fig. 3a), determination coefficient has a significantly higher value, i. e. in case of growth relations between the diameter and the height of sample trees there is a stronger dependency. The analysis of the relationship between the volume of a crown and the DBH of beech sample trees is interesting. In case of the sample trees from the CMT513 the determination coefficient is significantly lower than for sample trees from the CMT514b, which were cultivated by crown thinning with a positive selection (Fig. 4a, 4b). The mentioned fact confirmed that beech sample trees in the stand cultivated by crown (increment) thinning with the support of crop trees take up to 68% impact on diameter growth of a trunk. On the other hand, crown of beech sample trees which are in the upper layer of selection forest in a autonomous position for a long 2 time have determination coefficient R= 0.453, i. e. the capacity of a crown takes only 45% impact on a diame |