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ŠUMARSKI LIST 13/2005 str. 80     <-- 80 -->        PDF

IZLAGANJE NA ZNANSTVENOM SKUPU - PRESENTATION AT THE INTERNATIONAL SYMPOSIUM Šumarski list - SUPLEMENT (2005), 78-89
UDK 630* 372 + 377 +116


ŠUMSKA ŽIČARA LARIX - NJENA ULOGA U PRIRODI BLISKOM
GOSPODARENJU ŠUMAMA I POSEBICE
U SPRJEČAVANJU EROZIJE TLA


LARIX FOREST CABLEWAYS - IMPLEMENT OF NATURE
ORIENTED SILVICULTURE, ESPECIALLY
IN SOIL EROSION CONTROL


Premysl HOREK, Pavel MAUER, Lubomir NOVAK*


SAŽETAK: Moderna kretanja u ekološki orijentiranom europskom šumarstvu
uvode promjene u izboru metoda sječe i ističu kao najvažniji kriterij
brigu za šumski okoliš. Otprilike 80 % štete na tlu, stablima i poniku nastale
tijekom sječe otpada na izvlačenje -transport drva od sastojim do glavne
šumske ceste. Postupci izvlačenja koji vode računa o okolišu, a stoje svakako
zračni transport po žici, predstavljaju ekološku metodu iskorištavanja drva.
Osim toga, šumsko tlo pošteđeno je kompresije i abrazije.


Danas se prednost daje prebornom gospodarenju, a ne obnovi čistim sječama.
Cilj takvog gospodarenja je smanjiti elemente čiste sječe u češkim šumama
i uvesti finije sustave gospodarenja šumama. Preborni sustav je učinkovit
kod prirodne obnove u povoljnim prirodnim uvjetima. Za tu se svrhu na
teškim terenima svih vrsta koristi moderno dizajnirana šumska žičara, koja
općenito vodi računa o okolišu putem zračnog izvlačenja uzetom.


Model radnih postupaka koji uključuje načela ostvarivanja ciljeva prirodne
obnove šumske sastojine korištenjem izvlačenja uzetom s nekoliko tipova
šumskih žičara LARIX, pokazuje se na primjeru dugoročne uspješne prirodne
obnove bukovih sastojina u Šumskom centru Masaryk, Krtiny, Mendelevo
sveučilište poljoprivrede i šumarstva (Masaryk Forest Training Forest
Enterprise Krtiny, Mendel University of Agriculture and Forestry) u Brnu,
koje je provedeno bez oštećivanja stabala ili tla.


K Ij u č n e r ij e č i: prirodi blisko šumarstvo, mehanizacija sječe i privlačenja,
sustavi šumskih žičara LARIX, kontrola erozije tla.


1. UVOD - Introduction
Tri su objektivna razloga što će ubrzati razvoj tehtišta),
što predstavlja najmanje 10 % ukupne šumske
nologija privlačenja žičarom u bivšoj Čehoslovačkoj: površine.


1.
Godine 2000. sječa oblovine prelazila 15 milijuna 2. Postoji oko 90 šumskih žičara različitih tipova za
m , no volumen trupaca privučenih žičarama nije bio koje se zna da trenutno rade, a većina njih je zastariznad
300 tisuća m3, stoje samo 2 % ukupne količijele
konstrukcije. Moderne žičare domaće proizne,
s terenima u nagibu preko 40 % i terenima s nosivodnje
(tip LARIX) postepeno osvajaju lokalno trvim
kapacitetom nepovoljnim za traktore (trese-žište od 1996.
3.
U uvjetima mijenjanja šumskog gospodarenja sve
je veći naglasak na tehnologije prilagođene šumi
* Premysl llorek, Pavel Mauer, Lubomir Noväk
(blage), a privlačenje žičarom je bez ikakve sumnje


Mendelovo sveučilište poljoprivrede i šumarstva, Brno
Pokusno šumsko poduzeće Masarykova šuma u Krtiny jedna od najblažih metoda.




ŠUMARSKI LIST 13/2005 str. 81     <-- 81 -->        PDF

P. Horek, P. Mauer, L. Novak: ŠUMSKA ŽIČARA LAR1X - NJENA ULOGA U PRIRODI BLISKOM ... Šumarski list - SUPLEMENT (2005), 78-89
Promjena uvjeta u češkim šumama uključuje smanjeni
obujam elemenata čiste sječe, zagovaranje blažih
i obzirnijih metoda gospodarenja, tj. prebornom gospodarenju
daje se prednost pred obnovom čistom sječom.
Dozvole li prirodni uvjeti, preborni sustav djeluje zajedno
s prirodnom obnovom. Teški i nagnuti tereni traže
izvlačenje žičarom. Na tim teškim terenima metoda
prirodne obnove šume pomoću žičara obično se više
isplati zbog većih ekoloških i ekonomskih utjecaja
nego stoje to metoda prirodne obnove, budući da sustav
obnove čistom sječom na nagnutim terenima nosi
značajan rizik za šumski okoliš, te je skuplji. Međutim,


to se sprječava uporabom odgovarajućih uzgojnih postupaka
kao što je sječa u prugama (prema prof. Polansky)
i sa šumskom žičarom moderne konstrukcije (vidi
slika 1). Moderna žičara mora biti vrlo mobilna i jednostavna
za sastavljanje. Njena uporaba je djelotvorna
čim se radi o najmanje 50 m drva u jednoj operaciji
sječe. Osim toga, standardna žičara mora biti opremljena
radio kontrolom od mjesta pričvršćivanja tereta u
sastojini, jer je to jedini način kako odabrati radne postupke
s minimalnom štetom za pomladak, razvijeni
mladik i drveće matične sastojine.


2. PRAKTIČNA ISKUSTVA IZ OBRAZOVNOG ŠUMSKOG
PODUZEĆA MASARYK U KRTINY
Practical experience from the Masaryk forest training enterprise at Krtiny
Model radnih postupaka i potrebnih načela za postizanje
ciljeva prirodne obnove sastojina uz uporabu izvlačenja
žičarom LARIX moguće je demonstrirati na
primjeru dugoročne uspješne prirodne obnove bukovih
sastojina u Obrazovnom šumskom poduzeću (OŠP)
Masaryk u Krtiny, Mendelevog sveučilišta za poljoprivredu
i šumarstvo u Brnu. Poduzeće je osnovano prije
81 godinu kao ustanova posebne namjene, služeći
uglavnom Fakultetu za šumarstvo i drvnu tehnologiju
za pedagoške znanstvene i verifikacijske zadatke.


OŠP djeluje na 10300 hektara šume, što tvori neprekinuti
kompleks u neposrednoj vezi sa sjevernim granicama
grada Brna. Šumske sastojine nalaze se na visinama
između 210 m i 575 m. Prosječna godišnja temperatura
je 7,5 °C, srednje godišnje oborine dosežu 610
mm, a tek 360 mm u vrijeme vegetacije. Matična podloga
je granodiorit u zapadnom dijelu Poduzeća, devonski
vapnenac u središnjem, te kulmijanski sivi pješčanik
(gravaks) u istočnom. Topografija je sustavno
prekidana s izrazitim dubokim dolinama rijeke Svitave
i potoka Krtinsky, te brojnim postranim dolinama i valama.
Strmine od preko 34 % čine do jedne četvrtine
područja Poduzeća, što samo po sebi govori o dobrom
razlogu strukovnog interesa za šumske žičare. Raznolikost
prirodnih uvjeta je znatna i neupitna u Češkoj na
tako malom području. Pretežito su tu mješovite sastojine
u kojima su 46 % crnogorične vrste drveća, a 54 %
listače. Glavne vrste drveća su smreka, bor, ariš, bukva
i hrast. Obrazovno šumsko poduzeće u Krtini ima dugu
tradiciju primjene blažih metoda šumskog gospodarenja
specijaliziranog u primjeni prirodne obnove. Metode
blagog šumskog gospodarenja primijenjivane tijekom
dugog vremena uključuju sustav malih sječnih
površina i njihovih oblika obnove s oplodnim sijekom i
rubnom sječom, ali isto tako primjenu načela prebornog
gospodarenja.


Mnogi su slavni šumari ovdje radili, kao Leopold
Grabner-še f Šumskog područja, što je nekada bilo u


vlasništvu obitelji Liechtenstein, koji je 1848-1897. g.
uveo projekt prema kojemu su šume bile tako poredane,
da su svakih deset godina iznova bile obrađivane u pet
elaborata šumsko-gospodarstvenih planova za kontrolni
sustav Saske prema Cotti. Čiste sječe bile su postupno
smanjivane i zamjenjivane blagim oplodnim sječama u
odjelima, tj. prebornim sječama. Jak naglasak štavljenje
na mjere njege, koje su do tog vremena bile zanemarene.


Drugi istaknuti šumar bio je Julius Wiehl, koji je
izradio gospodarski plan modernog koncepta na prijelazu
19. u 20. stoljeće, po kojemu je uveden sustav uravnoteženih
dobnih razreda i gospodarenje prema sastojinama.
Julius Wiehl je namjerno prihvatio oblik oplodne
sječe u malim površinama jednodobnih sastojina. Ta
je metoda značila prirodnu koncepciju kreativne i samoodržive
šume.


Imena šumara što su radili u šumama OŠP u modernoj
povijesti i danas su profesori Konsel, Hasa,
Opletal,Polansky,Dolezal,Vyskot,Tesari
Kantor. Oni su osobno doprinijeli detaljnoj preciznosti
posebne metode gospodarenja bukvom u sustavu
oplodne sječe, koja postupno prelazi u rubni sijek. Ta
se metoda snažno proširila posljednjih deset godina
čak i na teškim terenima, zahvaljujući primjeni žičara
LARIX.


Dobro je gospodarenje bukovim sastojinama u OŠP
također potvrđeno činjenicom, daje OŠP vlasnik certifikata
Woodmark FSC za sirovo i piljeno drvo, dodijeljeno
poduzeću prije sedam godina, a od 2003. posjeduje
i PEFC.


Posebna metoda obnove i njege bukove sastojine
primijenjena u Obrazovnom šumskom poduzeću usmjerena
je na maksimalno korišćenje prirodne obnove i prirasta.
Bukove sastojine obnavljaju se u relativno dugom
(do 40 godina i više) razdoblju. Sa sadašnjim razdobljem
ophodnje od 130 godina, prve se odrasle šume
pojavljuju već u sastojinskoj dobi od 90 godina. Stoga
je potrebno stvoriti uvjete za rast i samooplodnju, te




ŠUMARSKI LIST 13/2005 str. 82     <-- 82 -->        PDF

P. Horek. P. Mauer, L. Novak: ŠUMSKA Ž1ČARA LAR1X - NJENA ULOGA U PRIRODI BLISKOM ... Šumarski list - SUPLFMLNT (2005). 78-89
sljedeću prebornu sječu već pri primjeni posljednjih
mjera njege. Sastojinc koje treba obnoviti moraju se podijeliti
s oko 100-120 m širokim stazama žičare, tj. rubnim
sječama, čija bi širina bila 4-5 m. Treba obratiti pozornost
na načelo u primjeni tih mjera, prema kojemu je
čitava rubna širina posječena tek kada nastupi propisno
izvlačenje žicom, no moguć je tek najuži usjek za omogućavanje
tog zahvata od otprilike tri metra široke žične
staze, koja će se proširiti na traženu širinu rubne sječe
prema Polanskom, tek nakon što se obavi čitav zahvat
sječe. Na taj će se način ukloniti drveće duž linije, koje
bi se vjerojatno oštetilo tijekom izvlačenja.Tada posječeni
rub postaje ishodišna točka za prirodnu obnovu,
koja se pomiče ispod matične sastojine odozdola. Sječa
se obavlja u kontekstu preborne sječe, čiji se intenzitet
smanjuje od rubne linije žičare prema unutrašnjosti sastojine.
Ovaj se preborni zahvat obavlja duž obih strana
staze žičare, a rezultira uklanjanjem drveća uglavnom
velikih promjera s nepravilnim deblima ili krošnjama od
razine glavne sastojine do udaljenosti od žičare između
20 i 30 m. Kvalitetni primjerci sa savršenim krošnjama i
dobrim karakteristikama rasta ostavljaju se u sastojini
za sjeme. Uklanjanjem loše oblikovanih stabala velikih
promjera ostavljamo drveće glavnog i podstojnog sloja
malih promjera, što rezultira povećanjem svjetla na kva


litetnu drvnu masu. Rezultati istraživanja ukazuju da
prirast može u potpunosti nadoknaditi gubitke proizvodnje,
što se često bilježe pri uklanjanju drveća velikog
promjera. Dosljedna i pravovremena selekcija primjeraka
velikih promjera uz smanjeno razdoblje ophodnje
pomažu u sprječavanju razvoja lažnog srca (false heart),
što rezultira velikim ekonomskim gubicima. Pri sječi
načelno ostavljamo podstojno drveće, a to utječe na sastojinsku
mikroklimu za zdrav razvoj mladih stabala. Nakon
što je sastojina postupno posječena i osigurana,
uvode se druge sječe u originalni sustav rubnih sječa,
što postupno dovodi do potpune obnove čitave sastojine.
Opisani sustav gospodarenja bukovom sastojinom
dobar je primjer kvalitetnog sastojinskog gospodarenja.
Postoje brojni takvi primjeri u sastojinama OPŠ Krtiny,
koji potvrđuju pravilnost opisane metode.


S obzirom na tehnička gledišta izvlačenja žičarom
rabljena u gore spomenutim uzgojnim postupcima,
šumske žičare LARIX bile su ekskluzivno primijenjene
u OŠP Krtiny zadnjih 9 godina, a njeni tehnički parametri
i prikladnost odgovaraju prebornom sustavu u
pojedinim prebornim sječama. Sljedeća tehnička rješenja
žičara tipa LAR1X olakšavaju primjenu blagih metoda
izvlačenja u uvjetima prebornog sustava pri pojedinim
prebornim sječama.


3. TEHNIČKE KARAKTERISTIKE ŠUMSKIH ZICARA LARIX
Technical characteristics of Larix forest cableways
Žičarc LARIX 550 i 3T konstruirane su kao priključene
naprave na poljoprivrednom traktoru, gdje se stup
i vitla žičare nose na stražnjoj vezi na tri točke, a bubnjevi
drugog dijela s užadi nose se na prednjoj vezi na
tri točke.


To znači daje težina žičare jednakomjerno raspoređena
na dvije osovine, što čini traktor sa žičarom mobilnim
i na teškom terenu.


LARIX 550 i 3T opremljeni su s pet kablova: zračno
izvlačenje, nosivo uže, podizno uže, uže za otpuštanje,
pomoćno uže.


Sustav beskonačne linije omogućava da se teret za
vrijeme transporta ne koči, a vrlo je jednostavno upravljati
vozilom sa ili bez tereta. Ciljana automatizacija
uvlačenja i izvlačenja tereta je u standardnoj opremi.


Žičare su radio-kontrolirane iz šume.


Slika 1. Rubna sječa prema Polanskom izvedena sa žičarom Slika 2. LARIX 3T u Nacionalnom parku prirode Češka
LARIX 550 u OŠP Krtiny, Republika Čehoslovačka Švicarska, Decin, Republika Čehoslovačka


Figure 1 Strip felling by Polansky made with the LARIX 550 Figure 2 LARIX 3T in National Natural Park Czech Switzerland,
cableway in TFE Krtiny, Czech Republic Decin, Czech Republic


S0




ŠUMARSKI LIST 13/2005 str. 83     <-- 83 -->        PDF

P. Horek. P. Mauer. L. Novak: ŠUMSKA ŽIČARA LARIX N.ILNA ULOGA U PRIRODI BLISKOM ... Šumarski list - SUPLF.MF.NT (2005). 78-89
Model -Model
Snaga motora traktora - Engine power of the tractor
Kapacitet žičare* -Line capacity*
Nosivo uže -Skyline
Beskonačno uže -Endlessline
Podizno uže -Hoistline
Uže za otpuštanje -Slackpulling - Une
Pomoćno uže (PP tekstil) -Strawline (PP-textile)
Izvlačenje / brzina - Line pull /speed
Nosivo uže -Skyline
Beskonačno uže (privlačenje) -Endlessline (haul-in)
Povratno uže (odvlačenje) -Endlessline (haul-back)
Podizno uže -Hoistline
Utovar - maksimalno preporučljivo -Loading -MaxPostran i doseg -Lateral reach
Težina -Weight
Stup s vitlima i užadi - Tower with winches and lines


Recommended


Pohranjivanje bubnjeva s užadi - Storage drums with lines
Visina stupa Tower height
pri radu -in operation
pri izvlačenju -in transport


LARIX 550
45kW+


550 m/ 16 mm
1400 m / 11,2 mm
200 m/11,2 mm
1100 in / 5 mm


40 kN/2,2 ms-´
20 kN/2,2 ms"1
8 kN / 5 ms"´
25 kN 1,5 ms ´
2000 kg
60 m


2450 kg
1200 kg


6,5 m
4m


LARIX 3T
70kW+


600 m / 18 mm
1500 m/ 12.5 mm
200 m/ 12.5 mm
600 m / 8 mm
1200 m/8 mm


50 kN / 3 ms´1
26 kN/ 2.5 ms´1


10 kN/5.3 ms-´
32 kN 1.5 ms´1
3050 kg
70 m


3050 kg
1400 kg


6,5 m
4m


* Postoji mogućnost uporabe kompaktnih žica PYTHON, tadaje transportna udaljenost 800 m.
* There is a possibility to use PYTHON compact lines and then the yarding distance is 800 m
LARIX Hydro -LARIX Hydro


Hidrostatički pokretani žičani sustavi LARIX
hydro konstruirani su za transport trupaca, kako uzbrdo,
tako i nizbrdo. Sustav je nadograđen na kamionu sa
stacionarnim motorom (LARIX Hydro A), ili na
posebnoj prikolici većeg poljoprivrednog traktora s
minimalnom snagom motora oko 100 kW (LARIX Hydro
P).


Između glavnog užeta i bubnja za povrat užeta je
međusustav s obnavljanjem snage kočenja, što omogućava
automatsko upravljanje s komandama za skladištenje
i programiranom izmjenom kolica s teretom i
bez njega. Vrijeme podešavanja je vrlo kratko. Neovisnost
o daljinskom upravljanju - na mjestu istovara je
daljinsko upravljanje, a na mjestu sječe je radio-kontrola.
Tehnički parametri su sljedeći:


Izvlačenje nizbrdo, uzbrdo, ili na ravnim terenima;


Stacionarni motor IVECO AIFO, 4 -eil. turbodiesel


125 KS;


Hidraulika SAUER SUNDSTRAND-DANFOSS,


odvojeni strujni krugovi za svaki bubanj;


Ugradnja na kamion ili prikolicu;


Opremljeno sa nosivim, glavnim, povratnim uze


tom za otpuštanje ipodiznim uzetom;


Hidrostatički pogon daje punu kontrolu užadi;


Spojni sustav (interlock) između glavnog i povrat


nog užeta;


Automatski i programirani pogon vozila s teretom i


bez njega;


Slika 3. LARIX Hydro u Francuskim Alpama, Barcelonnett,
Francuska


Figure 3 LARIX Hydro in the French Alps, Barcelonnett, France


Vrijeme namještanja je vrlo kratko;


Nije potrebna kabina zbog daljinske kontrole.


Metode djelovanja


2-žični sustav (nosivo i glavno uže) izvlačenje uzbrdo
pomoću gravitacijskog vozila Moko-25 s diesel
motorom, pogodnost s ovješenim povlačenjem
niz glavno uže.


3-žični sustav (zračna, glavna i odvlačna žica) nizbrdo,
uzbrdo s motornim kolicima Moko-25.


4-žični sustav (nosivo, glavna, uže za otpuštanje i povratno
uže) nizbrdo, uzbrdo s mehaničkim kolicima
KOS-2.


ŠUMARSKI LIST 13/2005 str. 84     <-- 84 -->        PDF

P. llorek. P. Mauer. L. Novak: ŠUMSKA ŽIĆARA LAR1X NJliNA ULOGA U PRIRODI BLISKOM ... Šumarski list - SUPLEMENT (2005). 78-89
2-žična metoda 3-žična metoda 4-žična metoda


Tehnički podaci za LARIX Hydro


2-line method 3-line method 4-line method


Technical data LARIX Hydro


uzbrdo -uphill uzbrdo, nizbrdo -uphill, downhill
Motor Engine IVECO AIFO, 4-cil. turbo diesel, 95 Kw -4-cyl. turbo diesel, 95 kW
Kapaciteti bubnja -Drum capacities
Nosivo uže 0 18 mm kompakt


700 m 700 m 700 m


Skyline 018 mm compact
Vučno uže 0 10 mm kompakt


750 m 1550 m 750 m


Main line 010 mm compact
Povratno uže 0 10 mm kompakt


— 750 m 1500 m
Back line 0 10mm compact


Uže za otpuštanje 0 6 mm


—-700 m


Slack pulling line 0 6 mm


Podizno uže 0 8 mm polyprop.


1100 m 1100 m 1100 m


Rig up line 0 8 mm polyprop.
Sidrena užad 0 18 mm - Guy lines 0 18 mm 4 x 60 m 4 x 60 m 4 x 60 m
Vučna sila -Pulling capacity
Nosivo uže - konstantni napon


90 kN 90 kN 90 kN


Skyline -constant tension
Vučno uže - Main line 32 kN 32 kN 32 kN
Povratno uže - Haul back line 32 kN 32 kN
Uže za otpuštanje Slack pulling line lOkN
Brzina - Line speed varijabla -variable 0-7 m.s - 1
Visina stupa - Tower height 9 m


4 žični sustav s ovješenom žicom
„ .. „ . 4 line system with slack pulling line


Kolica-Carriage . „ ...


*,^,,^ -- 2-1 3-zicm sustav s motorom


MOKO-25 „


2 and 3 line system with engine
, _ , elektronska kontrola kabla -electronic cable control


Kontrola-Control ........ . . ,. ,,-,,,-,
daljinska radio-kontrola s mjesta utovara remote radio control from the loading place
Ukupna težina bez traktora - without carrier 8600 kg


Total weight s prikolicom — with trailer 11200 kg


Kolica MOKO-25 - Carriage MOKO-25
Kolica su namijenjena žičarama opremljenim no- uličnu crpku. Motor pokreće opremu za ovješeno izsivim,
vučnom, povratnim, ili samo nosivim i nosivom vlačenje niz glavno uže, te također hidraulični sustav
užadi. Kolica MOKO-25 ima ugrađen dicscl motor od za sidrenje kolica na nosivo uže, te za osiguranje tereta


5.5 kW (Lombardini), komandnu radio-stanicu i hidra- na željenu poziciju ispod nosivog užeta.


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P. Horek, P. Mauer, L. Novak: ŠUMSKA ŽIČARA LAR1X - NJENA ULOGA U PRIRODI BLISKOM Šumarski list SUPLFMLNT (2005), 78-89
Slika 4. Kolica MOKO-25 u Orlicke hory, Destna, Republika
Čehoslovačka


Figure 4 Carriage MOKO-25 in Orlicke hory, Destna, Czech


Republic
snaga motorautovar maks.
- snaga otpuštauporaba dizcl- težinanja 4,2 kN
skog ulja na 8 sati
5,5 kW
2500 kg
maks. 2 1
560 kg
Kolica KOS-2 Carriage
KOS -2


Kolica su mehanička. Namijenjena su žičarama
opremljenim nosivim uzetom (promjera od 16 mm do
20 mm), vučnim kablom (10-13 mm), povratnim uzetom
(10-13) i uzetom za otpuštanje (5-6 mm). Kolica
KOS pružaju ovješeno povlačenje kraja vučnog užeta
od kolica pomoću pomoćnog kabla.


maksimalni utovar 3000 kg


- težina 245 kg
4. ZAKLJUČAK
Zašto dati prednost sječi sa zračnim izvlačenjem?
Otprilike 80 % oštećenja tla, drveća i mlade šume
tijekom postupka sječe otpada na zahvat izvlačenja prijevoz
trupaca iz sastojine do glavne šumske ceste.
Zahvat izvlačenja prilagođen okolišu stoga predstavlja
ekološku metodu sječe.
Metode okolišno usklađenog izvlačenja trupaca iz
šumske sastojine smanjuje ili eliminira vuču trupaca
po površini šumskog tla, kao što su sustavi polupodignutog
ili zračnog izvlačenja. Ostale metode što u tehničkom
smislu dolaze u obzir uključuju helikoptersku
izvlačenje, koje je krajnje skupo, jer ima ogromnu potrošnju
energije, a zračno izvlačenje je oko 2 do 3 puta
jeftinije, a može se primijeniti bez bitnih vremenskih
ograničenja, istovremeno je bitno manje bučno, ne
ometa niti izaziva stres kod divljači, ptica ili ljudi.


Slika 5. Kolica KOS u Parku prirode Cerdanya, La Molina.
Španjolska


Figure 5 Carriage KOS in Cerdanya Natural Park, La Molina,
Spain


Slika 6. LARIX 3T + MOKO-25 u OŠP Krtiny, Republika
Čehoslovačka


Figure 6 LARIX3T+ MOKO-25 in TFE Krtiny, Czech Republic


- Conclusion
Osim smanjenih zahtjeva u smislu gustoće mreže
šumskih puteva (u slučaju zračnog izvlačenja cestovni
je razmak 800 - 1000 m, a u slučaju izvlačenja traktorom,
taj razmak je 100 m), sustav šumskih zračnih žica
i njihovo djelovanje ne uzrokuje nikakvo oštećenje
šumskog tla kompresijom ili abrazijom, kao što se često
vidi pri uporabi tehnologija s kotačima (traktor) u
šumskim sastojinama. Povećana erozija tla prometom
zbog transmisije sila iz guma vozila na tlo, te posljedičnih
dugoročnih oštećenja šumskog tla jednostavno
se ne pojavljuje u slučaju uporabe šumskih žičara.


Nažalost, općenito je mišljenje šumara da su šumske
žičare primijenjivc samo u planinskim regijama.
To nijc sasvim istina u današnje vrijeme, jer šumske se
žičare mogu rabiti s obzirom na njihov višestruki karakter,
ne samo na svim terenima žičara u planinskim i




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P. Horck. P. Mauer, L. Novak: ŠUMSKA ŽIČARA LARIX NJENA ULOGA U PRIRODI BLISKOM Šumarski list - SUPLEMENT (2005). 78-89
gorskim krajevima, nego isto tako i u ravnicama, gdje
tereni mogu biti nepristupačni za vozila na kotače ili
prugu (traktore) zbog pojave velikih močvara, tresctišta,
pustopoljina, procjepa, usjeka, stijena, ili su dane
šumske sastojine pogođene katastrofalnim poplavama.
Uzmemo li u obzir sve negativne utjecaje i kriterije
uporabe traktora na padinama, te ih povežemo sa stvarnim
kapacitetom nosivosti tla, udjel terena sa žičarom
može se nadalje povećavati zbog okolišnih gledišta te s
obirom na zaštitu tla. Na taj će način tehnologija šumske
žičare često predstavljati jedino realistično rješenje
za ekološki prilagođeno izvlačenje i tehnologiju prijevoza
trupaca.


Obrazovno šumsko poduzeće Sume Masaryk u Krtiny
u sklopu Sveučilišta za poljoprivredu i šumarstvo
Mendel u Brnu održava dugu tradiciju primjene blažih


LITERATURADolezal, B., J. Truhlar: Analysis of forest management
systems used at the Training Forest Enterprise
Krtiny. Vol. I - III. (in Czech) University
of Agriculture in Brno, Brno, 1990: p. 858
Truhlar, J.: Silviculture in biological conception, (in
Czech) Training Forest Enterprise of Masaryk
Forest at Krtiny, Mendel Univ. of Agriculture
and Forestry Brno, Krtiny, 1996: p. 117 + attachments
N o v ä k, L.: Development and manufacture of skyline
cableways in the Training Forest Enterprise of
Masaryk Forest, Krtiny (in Czech). Proceedings


gospodarskih metoda u šumskim sastojinama uporabom
prirodne obnove. Takva visoka svrstanost je moguća
ne samo na temelju procjena načinjenih s obzirom
na šume pod konkretnim proizvodnim uvjetima,
nego i s obzirom na dug život šumskih sastojina i složeno
vrednovanje njihove povijesti. Nije zanemareno
niti stajalište odlučnih zahvata u šumu kao što su tehnologije
izvlačenja i vlake, što uključuje uporabu šumskih
strojeva, pristupačnost transportu, zaštitu šume,
provedbu prava lova, a jednako tako i stajalište samog
šumskog gospodarenja.


Nedavno praktično iskustvo pokazuje da su žičare
LARIX dobro pomagalo u ekološkom i potrajnom šumskom
gospodarenju zahvaljujući njihovim podesnim
tehničkim parametrima.


-
References
from International Seminar on the Use of LARIX
skyline cableway in sheltcrwood system of
forest management, Masaryk Forest Training
Forest Enterprise Krtiny, Mendel Univ. of Agriculture
and Forestry Brno. Krtiny, 2000: p. 9
Horek, P.: LARIX forest cableways in conditions of
sheltcrwood system /in Czech/. Proceedings
from international conference "Logistics in
technical production of wood in the Carpathians",
Technical University Zvolen, Zvolen
2002, pp. 73-79.




ŠUMARSKI LIST 13/2005 str. 87     <-- 87 -->        PDF

PRESENTATION AT THE INTERNATIONAL SYMPOSIUM
Šumarski list SUPLF.MhNT (2005), 78-89


LARIX FOREST CABLEWAYS - IMPLEMENT OF NATURE
ORIENTED SILVICULTURE, ESPECIALLY
IN SOIL EROSION CONTROL


Premysl HOREK, Pavel MAUER, Lubomir NOVAK*


ABSTRA CT: The present trend of ecologically oriented European forestry
changes conditions for the selection of logging operations with the criterion
of friendliness to forest environment becoming main parameter. Approximately
80 % of damage to soil, standing trees and advance growth in the course
of logging process fall to the operation of skidding-timber transportation
from the stand to main forest road. Environment-friendly skidding operation,
which skyline yarding undoubtedly is, therefore represents an ecologocical
method of timber harvesting. Last but not least, forest soils are not disturbed
by compression and abrasion.


Selection under shelterwood system is now given preference over clearcut
regeneration logging in order to reduce the size of clearcut elements in Czech
forests and to force in finer systems of forest management. Shelterwood system
works with natural regeneration under favourable natural conditions and
the modern design of the forest cableway is used for this purpose in difficult
terrains of all kinds for generally environment-friendly skyline skidding.


Model work procedures including the principles necessary to achieve the
objectives of the forest stand natural regeneration with the use of skyline logging
by several types of LARIX forest cableway systems can be demonstrated
on the example of a long-term successful natural regeneration of beech
stands at the Masaryk Forest Training Forest Enterprise Krtiny, Mendel University
of Agriculture and Forestry in Brno, carried out with no damage to the
standing trees or soil.


Key words: environment-friendly forestry, mechanization of logging
and skidding operations, Larix forest cableway systems, soil erosion control.


1. INTRODUCTION
There arc 3 objective reasons in the Czech Republic 2. There arc about 90 forest cableways of different tythat
are going to accelerate the development of cable-pes known to be in operation at the present time and
way skidding technologies. The reasons are as follows: most of them are of obsolete design. Modern cable


ways of domestic production (type LARIX) gradu


1.
In 2000, the fellings of rough timber first got over
ally begin to win the local market since 1996.
15 mil. m3 but the volume of timber skidded by cableways
did not exceed 300 thousand m3. The latter 3. The changing conditions of forest management put
is only 2 % of the total with the terrains of gradients an ever greater emphasis on forest-friendly (mild)
over 40 % and terrains with unsuitable carrying calogging
technologies and there is no doubt that the
pacity for tractors (peatlands) representing at least cableway timber skidding is one of the mildest met10
% of the total forest area. hods.


The changing conditions of Czech forests include


* Premysl Horek, Pavel Maucr, Lubomir Novak
the shrinking size of clear-felling elements, advocation
Mendel University of Agriculture and Forestry in Brno


of milder and more forest-friendly methods of mana


Training Forest Enterprise Masaryk Forest at Krtiny
C´Z 679 05 Krtiny 175, Czech Republic gement, i.e. that the shelterwood selection is winning




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P. Horek. P. Mauer. L. Novak: LARIX KORBST CABLEWAYS - IMPLEMENT OP THE NATURE ORIENTED ... Šumarski list - SUPLEMENT (2005), 78-89
preference over the regeneration clear fellings. If the
natural conditions allow, the shclterwood system can
work with natural regeneration. Difficult and sloping
terrains make use of cableway skidding. In these difficult
terrains, the method of natural forest regeneration
by means of cableways usually pays back with greater
ecological and economic effects than the method of artificial
regeneration since the clear-felling system on
steep slopes brings considerable risks for the forest environment
and is more costly. However, this can be
prevented by using suitable silvicultural procedures


2. PRACTICAL EXPERIENCE
such as strip felling (by Prof. Polansky) with the forest
cableway of modern design (sec Photo 1). A modern
cableway must be highly mobile and quick-to-assemble;
its use is efficient as soon as a single logging measure
would engage at least about 50 m3 timber. Also, a
standard cableway must be equipped with radio control
right from the place of load fastening in the stand since
this is the only way how to choose work procedures
with the minimum damage to self-seeding, advance
growth and standing trees of the parent stand.


FROM THE MASARYK FOREST


TRAINING ENTERPRISE AT KRTINY


Model working procedures and necessary principles
to reach the objectives of natural regeneration of
stands with using LARIX cableway skidding can be
demonstrated on the example of a long-term successful
natural regeneration of beech stands at the Training Forest
Enterprise Masaryk Forest at Krtiny (TFE Krtiny)
of Mendel University of Agriculture and Forestry in
Brno. The Enterprise was founded 81 years ago as a
special-purpose facility serving mainly the Faculty of
Forestry and Wood Technology to ensure paedagogic,
research and verification tasks.


TFE operates 10.300 hectares of forests which form
a continuous complex immediately linking with the northern
limits of the town of Brno. The forest stands are situated
at altitudes ranging from 210 to 575 m. Average
annual temperature is 7.5 °C, mean annual precipitations
amount to 610 mm and to merely 360 mm during
the growing season. Parent rock is granodiorite in the
western part of the Enterprise, Devonian limestone in
the central part, and Culmian grawacks in the eastern
part. The topography is heavily broken with conspicuous
deep valleys of the Svitava River and Krtinsky Brook
with numerous side valleys and glens. Slopes with gradients
over 34 % take up a quarter of the Enterprise area,
the fact which itself is a good reason to be professionally
interested in forest cableways. Diversity of natural
conditions is considerable and irrcpeatable in the Czech
Republic on such a small area. Prevailing are mixed
stands in which 46 % falls to coniferous tree species and
54 % to broadleaves. Main tree species are spruce, pine,
larch, beech and oak. The Training Forest Enterprise at
Krtiny has a long tradition in the application of milder
methods of forest management specialized in the use of
natural regeneration. The mild forest management methods
applied over a long time include the system of
small felling areas and its forms of shelterwood regeneration
and regeneration by border felling but also the application
of selection forest management principles.


There were many famous foresters working here
such as Leopold Grabner - boss of Forest District run


ning forests formerly owned by the family of Liechtenstein,
who introduced a project in 1848 1897 according
to which the forests were aligned and after each
ten years repeatedly treated in five elaborates of forest
management plans to the Saxonian area control system
by Cotta. Clear-fellings were gradually reduced and
mild compartment shclterwood fellings, i.e. selection
felling introduced. A great emphasis was put on all tending
measures which were neglected up to that time.


Another outstanding forester was Julius Wiehl who
worked out a management plan of modern concept at
the turn of the 19lh and 20th centuries, in which a system
of balanced age classes and management by stands
was introduced. Julius Wiehl intentionally adopted a
shelterwood form of the small-scale management of
even-aged stands. The method augured a natural conception
of the forest that would be steadily creative and
sustainable.


The names of foresters working with the TFE forests
in the modern history and today are those of professors
Konsel,Hasa,Opletal,Polansky,Dolczal,
Vyskot, Tesar and Kantor who personally
contributed to the detailed precision of a special
method of beech management in shelterwood system,


i.e. regeneration of beech stands by group shelterwood
felling which gradually melts into border cutting. The
method markedly expanded in the last ten years even in
difficult terrains thanks to the application of the LARIX
cableways.
Good management of beech stands at the Training
Forest Enterprise is also be documented by the fact that
TFE is a holder of the Woodmark FSC Certificate for
raw and sawn timber, awarded to the facility seven
years ago and since 2003 is a holder of PEFC too.


The special method of beech stand regeneration and
tending applied at the Training Forest Enterprise aims at
a maximum utilization of natural regeneration and
increment from the release. The beech stands arc regenerated
at a relatively long (up to 40 years and more)




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P. Horek, P. Mauer, L. Novak: LARIX FOREST CABLEWAYS - IMPLEMENT OF THE NATURE OR1KNTED ... Šumarski list SUPLHMENT (2005), 78-89
regeneration period. The present rotation period being
130 years, the first advance growths emerge as early as
at the stand age of 90 years. Therefore, it is necessary
that conditions are created for the rise of self-seedings
and subsequent shelterwood felling already at implementing
the last tending measure. The to-be regenerated
stands are to be divided by approximately 100 - 120 m
by inserting cableway routes, i.e. strip clear-fellings
whose width would be 4 to 5 m. There is a principle to
be observed at the measure implementation that the entire
strip width is not cut before the proper cableway
timber skidding takes place but it is only the narrowest
slit possible to enable the operation of an about 3 m wide
cableway which is going to be widened to the required
width of the strip felling by Polansky only after the
entire logging operation was accomplished. This is how
trees along the line can be removed, which were possibly
scratched while serving as fenders at skidding. Then
the felled strip-cut becomes a starting point for the natural
regeneration which shifts under the parent stand
from below. The logging is made in the context with
shelterwood felling the intensity of which is decreasing
from the cableway line edge into the stand inside. This
shelterwood treatment is made along the both sides of
the cableway route and results in the removal of mainly
large-diameter trees with ill-shaped stems or crowns
from the main stand level up to the distance of 20 - 30 m
from cableway reach. Qualitative individuals with perfect
crowns and good growing characteristics are left in
the stand for seed. By selecting the ill-shaped large-diameter
trees, we release main-level and sub-dominant


trees of smaller diameters, which respond to the release
with increased light increment on qualitative mass. Research
results indicate that the increment can fully compensate
production losses often recorded at the selection
of large-diameter trees. The consistent and timely selection
of large-diameter individuals together with the reduced
rotation period help to prevent the development
of false heart which can result in great economic losses.
At logging, we principally save the sub-dominant trees
which influence the stand microclimate for the sound
development of advance growths. After the stand has
been gradually felled and ensured, there are other fellings
inserted into the original system of strip fellings,
which gradually results in complete rgeneration of the
whole stand. The described system of beech stand management
is a good example of qualitative increment
management and there is a number of these examples in
the stands of TFE Krtiny, which can document correctness
of the above described method.


As to the technical aspects of cableway skidding
employed at the above mentioned silvicultural procedures,
it is the LARIX forest cableways which have
been exclusively used at the TFE Krtiny over the last 9
years, whose technical parameters and suitability correspond
the shelterwood system in individual selection
fellings. The following technical solutions of the LARIX
type cableways facilitate the application of mild
timber skidding methods in the conditions shelterwood
system in individual selection fellings.


3. TECHNICAL CHARACTERISTICS OF
LARIX FOREST


LARIX cableways produce the Czech firm Training
Forest Enterprise at Krtiny. The characteristic and parameters
of modern cableways LARIX and also carriages
are mentioned below.


LARIX 550 and LARIX 3T


The LARIX 550 and 3T cableways are designed as
trailed implements on agricultural tractor where the
tower and winches of the cableway are carried on the
rear three-point linkage, and another part drums with
running lines are carried on the front three-point linkage.


This means that the cableway´s weight is evenly
distributed onto the two axles, which makes the tractor
with the cableway mobile also in the difficult terrain.


The LARIX 550 and 3T is equipped with 5 cables:
skyline, running line, hoist line, slack- pulling line and
straw line.


The system with endless line make possible that
load during transport does not to be braked and there is


CABLEWAYS


very simple to direct the carriage with or without the
load, targeted automation of in hauling or out hauling
carriage is in standard equipment.


Cableways are radio-controlled right from the forest.


LARIX Hydro


Hydrostatic driven cable systems LARIX Hydro
are designed for timber transport, uphill as well as
downhill. The cable system is built either on a truck
with stationary motor (LARIX Hydro A) or on the special
trailer to a bigger agricultural tractor with minimum
engine power about 100 kW (LARIX Hydro P).


Between mainline and haulback line drum is an interlock
system with recuperation of braking power
what enables target automatic with storage commands
and programmed speed change of carriage with or without
the load. The set-up time is very short. Independence
of remote control - at landing place cable remote
control, at logging place radio control. Technical parameters
are as follow:




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P. Horek, P. Mauer, L. Novak: LAR1X FOREST CABLEWAYS IMPLEMENT OK THE NATURE ORIENTED Šumarski lisl - SUPLEMENT (2005). 78-89
Yarding downhill, uphill or on the flat grounds.


Stationary engine IVECO AIFO, 4 cyl. turbodiesel
125 hp
Hydraulics SAUER SUNDSTRAND- DANFOSS,


separate circuits for each drum
Built in either on a truck or trailer
Equipped with skyline, main line, haul back line,


slack pulling line, rig up line
The hydrostatic drive gives full control of the lines
Interlock system between main and haul backline
Automatic and programmable drive of carriage


with and without load


-
The set-up time is very short
No cabin is needed because of remote control
The operational methods


2 line system (sky and main line) uphill yarding by
means of gravity carriage Moko-25 with diesel engine,
comfort by slack pulling down the main line


3 line system (sky, main, and haul back line) downhill,
uphill with engine carriage Moko-25


4 line system (sky, main, haul back and slack pulling
line)downhill, uphill with mechanical carriage
KOS-2
Carriage MOKO-25


The carriage is intended for the cablcways equipped
with skyline, main line, haul-back line or only with


skyline and main line. The MOKO-25 carriage has a
built-in diesel engine of 5,5 kW (Lombardini), a command
radio station and a hydraulic pump. The motor
drives the equipment for slack pulling down the main
line and also the hydraulic system for anchoring the
carriage to skyline and to secure the load at wanted po


sition under skyline.
engine power- loading max.
power of slack pulling- consumption of diesel oil
per 8 hours- weight
5, 5 kW
2 500 kg
4, 2 kN
max. 2 1
560 kg
Carriage KOS -2


The carriage is mechanical. It is intended for the cableways
equipped by the skyline (of the diameter from
16 mm to 20 mm), mainline cable (10-13 mm), haul-
back line (10-13) and slack pulling line (5-6 mm). The
KOS carriage provides the slack pulling (dropped
down) the end of the main line from the carriage by
means of the auxiliary cable.


-
loading max. 3000 kg
-
weight 245 kg
4. CONCLUSION
Why to give preference to skyline logging?
Approximately 80 % of damage to soil, standing
trees and advance growth in the course of logging process
fall to the operation of skidding - timber transportation
from the stand to main forest road. Environment-
friendly skidding operation therefore represents an
ecologocical method of timber harvesting.


Methods of environment-friendly timber haulage
from the forest stand reduce or eliminate timber dragging
over the forest soil surface such as semisuspension
and air timber haulage systems. Other methods coming
technically into consideration include helicopter
skidding which is extremely costly and skyline logging
which is about 2 to 3 times cheaper since the helicopter
system is highly energy-consuming and can be applied
without any substantial weather limitations, being at
the same time markedly less noisy, not disturbing or
stressing wildlife, birds or people.


In addition to reduced requirements on forest road
network density (with road spacing in the case of skyline
logging to be 800 - 1000 m, in tractor skidding


100 m), the system of forest skylines and its operation
does not cause any damage to forest soil by compression
or abrasion as commonly seen when using wheeled
(tractor) skidding technologies in forest stands.
Increased soil erosion by traffic due to the transmission
of forces from the vehicle tyre onto the soil and consequent
long-term damage to forest soils simply do not
occur in the case of using the forest skylines.


Unfortunately, a generally prevailing opinion of foresters
considers the forest skylines to be applicable
only in mountain regions. This is not entirely true at the
present time as the forest skyline cablcways can be
used with respect to their versatile character not only in
all cableway terrains in montane and piedmont regions
but also in plains where the terrain may be inaccessible
to wheeled or tracked vehicles (tractors) due to the
occurrence of extensive bogs, peatlands, moors, boulders,
gullies, moraine incisions, or the forest stands in
question were affected by disastrous floods. If we take
into account all negative impacts and criteria of using
tractors on slopes putting them into relation also with
actual soil carrying capacity, the share of skyline ter




ŠUMARSKI LIST 13/2005 str. 91     <-- 91 -->        PDF

P. Horek. P. Maucr. L. Novak: LARIX FOREST CABLEWAYS IMPLEMENT OF
rains may further increase due to environmental and
soil-control aspects. This is how the technology of forest
skyline cableways can often represent the only realistic
solution of environment-friendly logging and
timber transport technology.


The Training Forest Enterprise Masaryk Forest at
Krtiny of the Mendel University of Agriculture and Forestry
in Brno maintains a long tradition in the application
of milder management methods in forest stands
with using natural regeneration. The statement and
high rating is made possible not only on the basis of assessments
made from the viewpoint of growing forests


IIIK NATURU ORIENTED ... Šumarski list SUI´LhMENT (200?), 78-89


in conrete production conditions but also with respect
to the long life of the forest stands and complex evaluation
of their history. Neither neglected is the viewpoint
of decisive operations in the forest such as logging and
skidding technologies including employed forest machines,
transport accessibility, forest protection, execution
of hunting rights and as a matter of course also the
viewpoint of forest management itself.


The recent practical experience indicates that the
cableways LARIX are a good helping hand in ecological
and sustainable forest management thanks to their
suitable technical parameters.




ŠUMARSKI LIST 13/2005 str. 92     <-- 92 -->        PDF

J. Gračan: BIOLOŠKA SANACIJA EROZIJE TLA Šumarski list SUPLF.MKNT (2005). W
2. Skupina referata:
BIOLOŠKA SANACIJA EROZIJE TLA


Skupu predsjedava: Dr. Joso Gračan


Referati ove skupine bave se pretežito pošumljavanjem površina u kojima su erozija i bujice već
učinili svoje. Tu se pretežito istražuju načini pošumljavanja golih površina s eventualnim ostacima nekadašnje
šumske vegetacije, a nekada i bez ikakvih njezinih tragova uz rijetku pojavu najotpornijih biljnih
vrsta. Održano je 6 referata 5 su održali znanstvenici iz Hrvatske ijedan iz Slovačke.


O stručno izvrsno zamišljenoj i vrlo uspjeloj kombiniranoj sanaciji erozije i bujica Senjske drage za


početoj u 18. stotjeću govorio je Ivančević. Ta sanacija erozije i bujica, ali i vodozaštite pripada zasigur


no prema učinkovitosti u najuspješniji projekt takve vrste u Sredozemlju.


Gračan i dr. izložili su rezultate istraživanja biološke sanacije u Lici i Istri koje su postavili šumari ge


netičari. Perić i dr. obradili su načine pošumljavanja površinskih kopova i deponija nastalih prilikom iz


gradnje autoceste Zagreb-Split u području Dalmacije dok Durbešić i Milković referiraju o uspjesima


biološke sanacije Svilaje započete 1960. godine.


Cavlović, Oršanić i Božić ukazali su na loše stanje protuerozijske, ali i ostalih općekorisnih funkcija
u privatnim šumama Zagrebačke županije zbog njihove slabe stabilnosti i strukture, dok je Kucbel istraživao
u planinskim šumama Niskih Tatri u Slovačkoj te ukazao na potrebu održavanja stabilne i prirodno
obnovljene sastojine u kategoriji zaštite.


2´"´ group of papers:


BIOLOGICAL RECOVERY OF SOIL EROSION


Chaired by: Joso Gračan, PhD


The papers in this group treat afforestation of areas already degraded by erosions and torrents.
Investigations mainly deal with methods of afforesting hare areas containing some or no remnants of
former forest vegetation, or some rare hut highly resistant plant species. Six papers were presented in
all: five by Croatian scientists and 1 by a Slovakian scientist.


Ivančević discussed the expertly planned and successfully executed combined regulation of erosion
and torrents in Senjska Draga, which began in the 18"´ century. In terms of efficiency, this erosion and
torrent regulation, as well as water protection activities, definitely rank among the most successful projects
of this kind in the Mediterranean.


Gračan et al. presented the results of research on biological recovery in Lika and Istria undertaken
by forest geneticists. Perić et al. dealt with methods of afforesting surface mines and landfills resulting
from the construction of the Zagreb-Split motorway in Dalmatia, whereas Durbešić and Milković
reported on the successful biological restoration ofSvilaja, begun in 1960.


Cavlović, Oršanić and Božić warned of the unsatisfactory condition of the anti-erosive and other
non-commercial forest functions in private forests in Zagreb County arising from their poor stability and
structure. Kucbel carried out research in montane forests of Nizke Tatre in Slovakia and stressed the
need to maintain stable and naturally regenerated stands in the protection category.