Aegjärkse raie mõju männikute alustaimestikule
Laen...
Kuupäev
2023
Kättesaadav alates
05.09.2023
Autorid
Kaja, Karel
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Järjest rohkem tekitab ühiskonnale muret laialdane lageraie teostamine metsades. Heaks
alternatiivseks lahenduseks küpsete metsade majandamisel on teiste turberaieviiside
kõrval aegjärkne raie. Käesoleva bakalaureusetöö eesmärgiks on uurida aegjärkse raie
mõju männikute alustaimestikule. Töös uuritakse seitsme katseala inventeerimisandmete
põhjal muutusi, mis toimuvad peale aegjärkset raiet puhma-rohurinde ja samblarinde
liigirikkuses ning liigilises koosseisus. Lisaks tehti välitööde käigus igal püsiprooviruudul
puhma-rohurinde kohalt poolsfäärifoto, mida kasutati valgustingimuste hindamiseks.
Andmed koguti ühtekokku 96-lt püsiprooviruudult 9-10. aastal pärast raie algust. Kogutud
andmeid võrreldi juhendaja poolt enne raiet, 1 aasta peale raiet ja 3-4 aastat peale raiet
kogutud andmetega.
Töö tulemustest selgus, et raiega põhjustatud häiringu ja valgustingimuste muutuse tõttu
osad liigid taanduvad ning juurde lisanduvad valguslembesed pioneerliigid, kuid ca 10
aastat peale raiet on soontaimede ja sammaltaimede arv suurem kui enne raie algust.
Lisandunud oli 22 soontaimeliiki ja 4 sammaltaimeliiki, ent samblarinde üldkatvus
vähenes oluliselt. Lisaks selgus, et aegjärkse raiega metsa majandamine sobib harilikule
mustikale ja harilikule pohlale. Muutused pooleli olevate ja lõpetatud raiealade
taimestikus olid üldiselt sarnased, kuigi lõpetatud alade liigiline koosseis erines oluliselt
pooleli aladest. Kokkuvõtvalt võib öelda, et aegjärkne raie on säästev raieviis, mis sobib
palumetsades hästi alternatiiviks lageraiele, säilitades looduslikku mitmekesisust ja
liigirikkust.
Society is more and more concerned about widespread clear-cutting (CC) in forests. A good alternative for the management of mature forests is regular shelterwood (SW) together with other SW cutting methods. The aim of this thesis is to study the effects of regular SW on the understorey vegetation. The study relies on data collected from seven experimental areas and describes the changes in the species richness and composition of vascular plants and bryophytes. Hemispherical photographs were also taken on each plot above the vascular plant layer to describe the light conditions. Data were collected from 96 permanent vegetation plots 9-10 years after the beginning of harvest. Data were compared with pre-harvest, 1 year after felling and 3-4 years after felling data collected by the supervisor. The results showed that due to the disturbance caused by felling and the change in light conditions, some species retreated and light-demanding pioneer species appeared. Therefore, around 10 years after felling the number of vascular plants and bryophytes was higher than pre-harvest. 22 vascular plant species and 4 bryophyte species had added, but the overall coverage of the bryophyte layer had decreased significantly. In addition, it turned out that forest management with regular SW is suitable for bilberry and cowberry. Changes in vegetation characteristics between felling areas with completed or uncompleted SW cycle were in general similar, although compositional differences were evident. In summary, regular SW is a sustainable harvesting method that offers a good alternative to CC in dry boreal forests, preserves biodiversity and species richness.
Society is more and more concerned about widespread clear-cutting (CC) in forests. A good alternative for the management of mature forests is regular shelterwood (SW) together with other SW cutting methods. The aim of this thesis is to study the effects of regular SW on the understorey vegetation. The study relies on data collected from seven experimental areas and describes the changes in the species richness and composition of vascular plants and bryophytes. Hemispherical photographs were also taken on each plot above the vascular plant layer to describe the light conditions. Data were collected from 96 permanent vegetation plots 9-10 years after the beginning of harvest. Data were compared with pre-harvest, 1 year after felling and 3-4 years after felling data collected by the supervisor. The results showed that due to the disturbance caused by felling and the change in light conditions, some species retreated and light-demanding pioneer species appeared. Therefore, around 10 years after felling the number of vascular plants and bryophytes was higher than pre-harvest. 22 vascular plant species and 4 bryophyte species had added, but the overall coverage of the bryophyte layer had decreased significantly. In addition, it turned out that forest management with regular SW is suitable for bilberry and cowberry. Changes in vegetation characteristics between felling areas with completed or uncompleted SW cycle were in general similar, although compositional differences were evident. In summary, regular SW is a sustainable harvesting method that offers a good alternative to CC in dry boreal forests, preserves biodiversity and species richness.
Kirjeldus
Bakalaureusetöö
Metsanduse õppekaval
Märksõnad
bakalaureusetööd, aegjärkne raie, alustaimestik, soontaimed, sammaltaimed, palumetsad