DIGITALNA ARHIVA ŠUMARSKOG LISTA
prilagođeno pretraživanje po punom tekstu
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. |
ŠUMARSKI LIST 13/2005 str. 85 <-- 85 --> PDF |
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 |
ŠUMARSKI LIST 13/2005 str. 86 <-- 86 --> PDF |
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 |
ŠUMARSKI LIST 13/2005 str. 88 <-- 88 --> PDF |
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) |
ŠUMARSKI LIST 13/2005 str. 89 <-- 89 --> PDF |
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: |
ŠUMARSKI LIST 13/2005 str. 90 <-- 90 --> PDF |
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. |