Aegjärkse ja häilraie mõjud alustaimestikule ja looduslikule uuendusele JS276-8 ja CO036-5 katsealadel
Laen...
Kuupäev
2021
Kättesaadav alates
08.09.2021
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Lageraie suhtes on ühiskondlik seisukoht sageli kriitiline. Seetõttu soovitatakse kasutada metsade uuendamisel rohkem alternatiivseid raieviise, näiteks turberaieid. Käesoleva bakalaureusetöö eesmärgiks on analüüsida kahe turberaieviisi – aegjärkse ja häilraie - mõjusid metsa alustaimestikule ja loodusliku uuenduse tekkele. Töös iseloomustatakse kahe katseala andmete põhjal, millised muutused toimuvad aegjärkse ja häilraie järel puhma-rohu- ja samblarinde liigirikkuses ning liigilises kooseisus. Samuti hinnatakse, kas kahel turberaieviisil on alustaimestikule sarnane või erinev mõju. Lisaks hinnatakse männi ja kase uuenduse teket.
Töö jaoks vajalikud andmed koguti alustaimestiku püsiprooviruutudelt JS276-8 ja CO036-5 katsealadelt 7-8 aastat pärast raiet. Välitööde käigus tehti ka iga püsiprooviruudu keskel puhma-rohurinde kohalt poolsfäärifotod, mida kasutati valgustingimuste kirjeldamiseks. Kogutud andmeid võrreldi juhendaja poolt enne raiet kogutud andmetega.
Tulemustest selgus, et raie-järgsed muutused alustaimestikus olid mõlema raieviisi korral enamasti sarnased. Raieviisil ei olnud mõju soontaime- ja samblaliikide keskmisele liigirikkusele prooviruutudel, samblarinde üldkatvusele ja kaseuuenduse arvukusele. Küll aga oli raieviisil mõju männiuuenduse arvukusele, mis oli arvukam aegjärkse raie korral. Lisaks tekkis häilu sees olevates püsiprooviruutudes oluliselt rohkem kaseuuendust, võrreldes häilust väljas olevate ruutudega. Kokkuvõtvalt võib öelda, et aegjärkne ja häilraie ei tekita suuri muutusi alustaimestikus.
The social opinion is often critical towards clear-cutting. Therefore, the wider use of alternative logging methods, such as shelterwood, is recommended for reforestation. The aim of this bachelor’s thesis is to analyse the effects of two shelterwood methods – regular shelterwood and gap felling – on the understorey vegetation and formation of natural regeneration. The paper relies on data collected from two experimental areas. The thesis describes the changes in the species richness and composition of vascular plants and bryophytes. It is also assessed whether the two shelterwood cutting methods have similar or different effects on the understorey vegetation. The formation of pine and birch regeneration is assessed as well. Data were collected from permanent vegetation plots in experimental areas JS276-8 and CO036-5 7-8 years after felling. Hemispherical photographs were also taken in the middle of each plot above the vascular plant layer. Photographs were used to describe the light conditions. Data were compared with pre-harvest data collected by the supervisor. The results showed that post-cutting changes in the understorey were mostly similar for two shelterwood methods. The effects of felling method on the average species richness of vascular plants and bryophytes in the vegetation plots, the total coverage of bryophytes and the abundance of birch regeneration were not significant. However, the felling method affected the number of pine regeneration, which was more numerous in the case of regular shelterwood felling. In addition, there were significantly more birch seedlings in the vegetation plots inside the gaps than in the plots outside the gaps. In summary, regular shelterwood and gap felling do not cause major changes in the understorey vegetation.
The social opinion is often critical towards clear-cutting. Therefore, the wider use of alternative logging methods, such as shelterwood, is recommended for reforestation. The aim of this bachelor’s thesis is to analyse the effects of two shelterwood methods – regular shelterwood and gap felling – on the understorey vegetation and formation of natural regeneration. The paper relies on data collected from two experimental areas. The thesis describes the changes in the species richness and composition of vascular plants and bryophytes. It is also assessed whether the two shelterwood cutting methods have similar or different effects on the understorey vegetation. The formation of pine and birch regeneration is assessed as well. Data were collected from permanent vegetation plots in experimental areas JS276-8 and CO036-5 7-8 years after felling. Hemispherical photographs were also taken in the middle of each plot above the vascular plant layer. Photographs were used to describe the light conditions. Data were compared with pre-harvest data collected by the supervisor. The results showed that post-cutting changes in the understorey were mostly similar for two shelterwood methods. The effects of felling method on the average species richness of vascular plants and bryophytes in the vegetation plots, the total coverage of bryophytes and the abundance of birch regeneration were not significant. However, the felling method affected the number of pine regeneration, which was more numerous in the case of regular shelterwood felling. In addition, there were significantly more birch seedlings in the vegetation plots inside the gaps than in the plots outside the gaps. In summary, regular shelterwood and gap felling do not cause major changes in the understorey vegetation.
Kirjeldus
Bakalaureusetöö
Metsanduse õppekaval
Märksõnad
bakalaureusetööd, turberaie, soontaimed, samblad, mänd