Tuulekahjustused viljakates kuusikutes
Laen...
Kuupäev
2018
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Tuulekahjustused võivad tekitada metsaomanikele suurt majanduslikku kahju. Kuusikute
tuulekahjustuse riski peetakse kõrgeks võrreldes teiste Eestis esinevate puuliikidega. Kõige
probleemsemateks peetakse kuuskede tuulekahjustusi viljakal maal asuvate lageraiega avatud
metsaservades. Antud bakalaureusetöö eesmärgiks oli uurida selliseid kuusikuid, mis lääne või
edela poolt jäid lageraie tõttu avatuks, kuna Eestis on valitsevad tuuled nendest ilmakaartest.
Töö koostamiseks koguti välitööde käigus andmed kümnest kuusikust, kus igal alal hinnati puistu
koosseisu, tagavara ja puistu tuulekahjustusi transektidel metsa servas ning puistu keskel.
Töö tulemused näitavad, et kahjustatud puude osakaal oli suurem metsa servaaladel, kuid erinevus
oli väike ning statistiliselt mitteoluline. Eelnevate uurimustööde põhjal oli alust arvata, et
kõrvaloleva avatud ala suurus mõjutab oluliselt tuulekahjustuste ulatust, kuid antud uurimustöö
põhjal see välja ei tulnud – puudekahjustuste osakaal ei sõltunud avatusest. Hüpoteesiks oli, et
kuused on tuule poolt rohkem kahjustatud kui teised puuliigid. Pigem oli kahjustatud puude
osakaal suurem hoopis muude puuliikide hulgas, kuigi statistiliselt mitteolulisena. Lamapuidu
kogus ei erinenud metsaservas ja -keskel olevatel transektidel, kuid oli siiski pisut suurem
metsaservades. Kõige rohkem leidus seal üle 10 cm diameetriga lamapuitu, mille kõduaste oli 1
või 2. Metsa keskel olevatel transektidel leidus ka kõige rohkem üle 10 cm diameetriga lamapuitu,
kuid puit oli rohkem lagunenud (kõduaste 3-5). Lamapuidu kogust mõjutas kõige rohkem hiljuti
surnud puude arv.
Töö järeldusi võis mõjutada ka küllalt väikene valim, seega järgnevates uurimustöödes võiks
suurendada valimi suurust ning mõõdetava ala pindala.
Wind damage causes major economic losses to forest owners. The risk of wind damage in spruce forest is considered to be higher compared to other tree spieces. In productive spruce forest the most wind damage occurs on newly clear-cut edges. The goal of the bachelor’s thesis was to examine areas where west and south-west sides were open due to clear-cutting because west and south-west winds are most common in Estonia. Data for this bachelor’s thesis was collected from 10 different spurce forests where forest composition, tagavara and wind damage at the edge of the forest and inside the forest were evaluated. The results of this bachelor’s thesis show that the proportion of wind damaged trees was higher at the edges of the forest, but the difference was small and statistically insignificant. Based on previous studies, there was reason to believe that the size of open area next to test areas had significant impact on the extent of wind damages, but this was not confirmed by this research. The proportion of wind damaged trees did not depend on openness. Hypothesis, that said spruces are more damaged by the wind than other tree spieces was not confirmed, because other tree spieces were more damaged by the wind, although it was not statistically insignificant. There was little bit more down timber at the edge of the forest, but it did not differ much from transects from inside the forest. The most of down timber were over 10 cm diameter, which glare level was 1 or 2. Down timber what was found in the middle of the forest also had a diameter over 10 cm but glare level was higher (3-5). The amount of down timber was affected by the number of recently deceased trees. Subsequent studies could increase the number and area of test areas. There should be this kind of studies in the future in order to obtain even more accurate and reliable results.
Wind damage causes major economic losses to forest owners. The risk of wind damage in spruce forest is considered to be higher compared to other tree spieces. In productive spruce forest the most wind damage occurs on newly clear-cut edges. The goal of the bachelor’s thesis was to examine areas where west and south-west sides were open due to clear-cutting because west and south-west winds are most common in Estonia. Data for this bachelor’s thesis was collected from 10 different spurce forests where forest composition, tagavara and wind damage at the edge of the forest and inside the forest were evaluated. The results of this bachelor’s thesis show that the proportion of wind damaged trees was higher at the edges of the forest, but the difference was small and statistically insignificant. Based on previous studies, there was reason to believe that the size of open area next to test areas had significant impact on the extent of wind damages, but this was not confirmed by this research. The proportion of wind damaged trees did not depend on openness. Hypothesis, that said spruces are more damaged by the wind than other tree spieces was not confirmed, because other tree spieces were more damaged by the wind, although it was not statistically insignificant. There was little bit more down timber at the edge of the forest, but it did not differ much from transects from inside the forest. The most of down timber were over 10 cm diameter, which glare level was 1 or 2. Down timber what was found in the middle of the forest also had a diameter over 10 cm but glare level was higher (3-5). The amount of down timber was affected by the number of recently deceased trees. Subsequent studies could increase the number and area of test areas. There should be this kind of studies in the future in order to obtain even more accurate and reliable results.
Kirjeldus
Bakalaureusetöö
Metsanduse õppekaval
Märksõnad
bakalaureusetööd, tormikahjustused, tuulemurrud, kuusikud