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K. Godina: RAZVOJ STRUKTURNIH ELEMENATA U MJEŠOVITIM SASTOJINAMA HRASTA ... Šumarski list br. 7–8, CXXXIII (2009), 407-416 tion of pendunculate oak, narrow ash and black alder distinguishes itself by even more intense extraction of the main tree species, so there are a great number of suppressed yet perspective (+-) and dry (-) penduculate oak trees (picture 5). After simulated harvest, the growth of mean tree was projected according to the tree species. Simultaneously with the vitality evaluation, the competition among neighbouring dominant trees was being determined, and the influence on lower perspective trees, primarily of the main species, was evaluated. The simulated harvest gave the advantage to pendunculate oak and the predominant and dominant trees of the secondary species were mainly removed. The structure of the stand did not involve dry (-) and too suppressed trees (-+), which, with the previously mentioned, gives the total simulated harvest (picture 6 and 7). This was the way the main stand was gained. A growth projections of the mean tree was performed for the main stand according to the tree species, and the structural elements were determined in this way after five years. The growth projection for a single subassociation was gained from samples of circumference and tree heights after total simulated harvest that could more represented the regularly managed stands. The height growth models during a period of time, for each of the three researched subassociations, are gained by equalizing of tree heights samples according to the modified Mihajlov function (formula 1) in aplication programme Statistica 6.0. The same way were obtained circumference growth models. A portion of the explained variability (R 2 ) is the largest in height growth models after total simulated harvest, and it is considerably lower in circumference growth models before the simulated harvest. Variability (S.D.) increases with the age increase, and there is a greater circumference variability in relation to the heights. The current diameter and height increment of the pendunculate oak is the biggest in subassociation with common hornbeam, while it is considerably lower and roughly equal in correlation within the remaining subassociations. The competition of the main stand trees is mostly manifested through the height increment in purpose of conquering the local area for undisturbed crown development. For all tree species in research stands, the height increment is mainly bigger, while the diameter increment is lower in relation to the yield table (picture 13–15). The basal areas and volume projections of researched mixed stands for the three age groups after the simulated harvest are considerably different in relation to the mensuration stand (picture 10–12). The differences in relation to the mensuration stand appear due to equalization of data by Mihajlov’s growth function, because the biggest amount of the diameter and height growth are realised within the first age group. Then, the volume of died and unqualitative trees, since they were not adequately and in time cut, increases mainly successively in relation to the first age group (table 2). Different volume projections reflect on the current volume increment, which is considered as accumulated iVt(a) and productive iVt(p). The accumulated current volume increment is the volume difference of the main stand at the end and at the beginning of the period (picture 16). The accumulated increment is under a strong influence of harvest, and it can be positive, negative or equal to zero. For pendunculate oak as the main species, a positive amount accumulates, while secondary species can also have negative amounts of the accumulated increment. The production current volume increment is an volume increase of the main stand until the next harvest. The productive increment depends mainly on structural elements of the mean tree and regards to prominent vertical structure of the mixed stand, on the number of trees and on giving the advantage to the main tree species for the undisturbed development. The productive current volume increment for all mixed stands is considerably bigger in relation to the yield tables (Špiranec, 1975), and in the second age group, the subassociations of the pendunculate oak and narrow ash are even bigger by 182 % (picture 17). This points to a very high development potential of young unmanaged mixed stands, which decreases with an increase in age as a consequence of mortality, falling off increments and harvest. There is a question of how to preserve the developmental potential in mixed stands. Silviculture interventions should be done in time in order to enable trees supstitutions from lower to higher layers and, on the basis of a spatial structure, an optimal diameter and height increment for the trees of the main stand. 416
IZVORNI I ZNANSTVENI ČLANCI – ORIGINAL SCIENTIFIC PAPERS UDK 630* 188 (001) Šumarski list br. 7–8, CXXXIII (2009), 417-423 ŠUME BUKVE S TRSTOLIKOM MILAVOM – As. Calamagrosti arundinaceae-Fagetum (Ht. 1950) Cerovečki ass. nov. NA PLANINAMA ZAPADNE HRVATSKE BEECH FORESTS AND MILAVA – As. Calamagrosti arundinaceae-Fagetum (Ht. 1950) Cerovečki ass. nov. OF THE MOUNTAIN OF WEST CROATIA Zdravko CEROVEČKI* SAŽETAK: Na graničnom području kopnenih i primorskih bukovih šuma, razvijaju se u smislu I. Horvata (1962) šume bukve s travom milavom (Calamagrostis arundinacea) koje smo opisali kao as. Calamagrosti arundinaceae-Fagetum (Ht. 1950) Cerovečki. ass. nov. Asocijacija je razlučena na dvije subasocijacije, termofilniju caricetosum albae i mezofilniju abietetosum albae. Subasocijacija s bijelim šašem obuhvaća čiste bukove šume, koje na Obruču nalazimo u fizionomskom pogledu kao dva različita tipa. Jednom pripadaju normalno razvijene visoko vrijedne gospodarske šume, koje obrašćuju znatne površine istraživanog područja, te šume bukve kržljavog izgleda, ograničene na produženu zaravan podno litice sjeveroistočno od najvišeg vrha Obruča. Potonji tip razvio se prema našem mišljenju utjecajem osebujnih klimatskih pri lika i karakterističnom orografijom masiva. Općenito uzevši područje Obru ča, Paklena, Crnog vrha i Sljemena osebujno je s obzirom na klimatske po jave i fitogeografsku pripadnost. Šume bukve i trstolike milave nastanjuju na spomenutom području umjereno nagnute padine i zaravni povrh rendzina na vapnencu ili srednje dubokih i dubokih tala između blokova stijena. Šume as. Calamagrosti arundinaceae-Fagetum podredili smo svezi Aremonio-Fagion, redu Fagetalia sylvaticae i razredu Querco-Fagetea. Ključne riječi: Vegetacija Hrvatske, bukove šume, as. Calamagrosti arundinaceae-Fagetum. Obična bukva (Fagus sylvatica) na području zapadne Hrvatske zauzima velike šumske komplekse, te je u šumsko-gospodarskom smislu jedna od najvažnijih vrsta drveća. Ima najveću ekološku amplitudu od svih naših šumskih vrsta. Nalazimo ju u vertikalnom smislu od granice primorskih termofilnih šuma do gornje granice šumske vegetacije najviših vrhova dinarskih planina. Na tom prostoru stvara veći broj asocijacija. Zna tan broj zajednica još nije detaljnije proučen, a neke su poznate samo na razini imena kao npr. šuma bukve i trstolike milave. Najstarija istraživanja bukovih i bukovo-jelovih šuma zapadne Hrvatske potječu od I. Horvata (1950, 1951, 1962, 1963) te I. Horvata i dr. (1974). * Zdravko Cerovečki, dipl. ing. šum., Zrinskog i Frankopana 18, 49000 Krapina, E-mail: unadrvo@yahoo.com UVOD – Introduction Kao što je poznato I. Horvat (1962) raščlanio je bukove šume dinarskog područja Hrvatske (Fagetum croaticum australe Ht. 1938) u vertikalnom smislu u četiri skupa: a. Skup primorske bukove šume – As. Fagetum croaticum seslerietosum autumnalis (Ht. 1950) b. Skup bukovih i bukovo jelovih šuma s milavom – As. Fagetum croaticum calamagrostetosum (Ht. 1950) c. Skup bukovo-jelovih šuma – As. Fagetum croaticum abietetosum (Ht. 1938) d. Skup subalpskih šuma bukve – As. Fagetum croaticum subalpinum (Ht. 1938) Bukove i bukovo jelove šume s travom milavom (As. Fagetum croaticum calamagrostetosum Ht. 1950), I.Horvat prvi puta spominje god. 1962, te navodi, da 417
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ŠUMARSKI LIST HRVATSKO ŠUMARSKO D
Page 3 and 4: UDK 630* (05):»54-02«/061.2 ISSN
Page 5 and 6: SADRŽAJ - CONTENTS IZVORNI ZNANSTV
Page 7 and 8: IZVORNI I ZNANSTVENI ČLANCI - ORIG
Page 9 and 10: M. Vedriš, A. Jazbec, M. Frntić,
Page 21 and 22: D. Matošević, M. Pernek, T. Dubra
Page 31 and 32: T. Dubravac, S. Dekanić: STRUKTURA
Page 47 and 48: K. Godina: RAZVOJ STRUKTURNIH ELEME
Page 53: K. Godina: RAZVOJ STRUKTURNIH ELEME
Page 57 and 58: Z. Cerovečki: ŠUME BUKVE S TRSTOL
Page 63 and 64: STRUČNI ČLANCI - PROFESSIONAL PAP
Page 65 and 66: R. Pašičko, D. Kajba, J. Domac: K
Page 77 and 78: STRUČNI ČLANCI - PROFESSIONAL PAP
Page 79 and 80: D. Grgurević: SUKULENTE (MESNATICE
Page 85 and 86: ZAŠTITA PRIRODE - NATURE PROTECTIO
Page 87 and 88: Korak po korak, nakon pola sata lag
Page 89 and 90: u datom povijesnom razdoblju, bez b
Page 91 and 92: đana ima o lovcima negativnu predo
Page 93 and 94: Split (31,2 %). Najniže vrijednost
Page 95 and 96: 3. Poštovani gospodine Jan Kickert
Page 97 and 98: IZ ŠUMARSTVA BOSNE I HERCEGOVINE F
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Page 101 and 102: Dana 1. travnja 2009. god. zate - k
Page 103 and 104: UPU TE AU TO RI MA - INSTRUCTIONS F
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