Puude varisevood kuusikute ja männikute metsaökosüsteemides
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Kuupäev
2017
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Metsa ökosüsteemides sisaldub umbes pool maismaa süsinikuvarust. Peamiselt
vähenevad kliimamuutused süsiniku sidumise tulemusel puitsesse biomassi ja
metsamulda.
Antud bakalaureusetöö keskendub metsa varisevoo uurimisele okaspuupuistute
metsaökosüsteemides. Töö põhineb 6 männi (Pinus sylvestris) ja 2 kuuse (Picea abies)
puistu metsavarise vaatlusandmetel. Puistud asuvad Lõuna- Eestis: Tartu- ja Põlvamaal.
Bakalaureusetöö eesmärgiks on kirjeldada männi ja kuuse puistute variseproduktsiooni
ning varise sesoonset dünaamikat erineva vanustega puistutes.
Varise langemise intensiivsuses eristus selgelt kaks kulminatsiooni – kevad-suvine ning
sügisene. Talvel jäi varise langemine miinimumi. Antud töös käsitletud okaspuupuistutes
moodustasid metsavarise okkad, oksad ja muu varis. Töö käigus selgus, et varise
fraktsionaalne koostis ja produktsioon erinevad puistutes vanuse ja peapuuliigi poolest.
Samuti avaldas varisele mõju ka eelmisel aastal läbi viidud harvendusraie. Aastane
varisehulk jäi 17- kuni 66-aastastes männikutes vahemikku 2.4-4.7 t/ha, 30- kuni 61-
aastastes kuusikutes 1.2-4.5 t/ha.
Approximately half of the carbon stock is located in forest ecosystems. Climate changes are mainly mitigated by sequestrating carbon fluxes into woody biomass and forest soils. The study is based on litterfall observations in four different Scots pine (Pinus sylvestris) and two Norway spruce (Picea abies) stands between ages of 17-66 and 30- 61 years, respectively. Stands are located in southern part of Estonia, Tartu and Põlva county. The aim of this thesis was to describe and analyze litter production and litterfall dynamics in different coniferous forest ecosystems. The intensity of litterfall differed clearly in two maximums – in spring-summer and autumn period. The litter consisted of following fractions: needles, branches and litter of other origin. The results showed that the fractional composition of litter and its production differ by stand age and main tree species. Also the process of forest thinning affected tree litter. The yearly amount of litter in Scots pine stands varied between 2.4 and 4.7 tons per hectare. And the number for Norway spruce stand was in the range of 1.2 and 4.5.
Approximately half of the carbon stock is located in forest ecosystems. Climate changes are mainly mitigated by sequestrating carbon fluxes into woody biomass and forest soils. The study is based on litterfall observations in four different Scots pine (Pinus sylvestris) and two Norway spruce (Picea abies) stands between ages of 17-66 and 30- 61 years, respectively. Stands are located in southern part of Estonia, Tartu and Põlva county. The aim of this thesis was to describe and analyze litter production and litterfall dynamics in different coniferous forest ecosystems. The intensity of litterfall differed clearly in two maximums – in spring-summer and autumn period. The litter consisted of following fractions: needles, branches and litter of other origin. The results showed that the fractional composition of litter and its production differ by stand age and main tree species. Also the process of forest thinning affected tree litter. The yearly amount of litter in Scots pine stands varied between 2.4 and 4.7 tons per hectare. And the number for Norway spruce stand was in the range of 1.2 and 4.5.
Kirjeldus
Bakalaureusetöö
Loodusvarade kasutamise ja kaitse erialal
Märksõnad
bakalaureusetööd, süsinikuringe, okaspuud, puistud, ökosüsteemid, harvendusraie