Puuliigi osakaalu mõju puistu süsiniku sidumisele keskealises kuusekase segametsas
Laen...
Kuupäev
2016
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Käesoleva töö eesmärgiks oli hinnata 30. aastase jänesekapsa kasvukohatüübis kasvava
kuuse-kase segametsa puistu maapealse osa biomassi produktsiooni ja selles akumuleerunud
süsiniku kogust.
Puistu maapealse osa biomassi ja produktsiooni leidmiseks kasutati mudelpuude meetodit
(Bormann & Gordon 1984, Lõhmus et al. 1996).
Uuritud kuuse-kase segapuistu maapealse osa biomassid olid 163,6 ja 145,9 t ha-1 (kuivaines)
vastavalt suuremale või väiksemale kuuse osakaalule puistu koosseisus. Puistu keskmine
aastane tüvemassi produktsioon ei sõltunud kuuse osakaalust puistus ja varieerus vahemikus
3,8...3,9 t ha-1 (kuivaines). Küll oli aga erinev kogu maapealses biomassis seotud süsiniku
kogus, vastavalt 10,6 ja 8,2 t ha-1 suurema ja väiksema kuuse osakaaluga aladel. Keskealises
kuuse-kase segapuistus (30 a.) jõudis maapealse varisega mulda aastas süsinikku 1,02 t ha -1
ja 1,3 t ha -1
, vastavalt suurema ja väiksema kuuse osakaaluga aladel. Saadud tulemuste põhjal
võivad kuuse-kase segapuistud jänesekapsa kasvukohatüübis olla väga produktiivsed, ületades
Eestis kasutusel olevate kuuse ja kase kasvukäigutabelite vastavaid väärtusi. Saadud
tulemused täiendavad seniseid teadmisi taoliste puistute arengust ja kasvukäigust ning on
kasutatavad puistute kasvu modelleerimisel.
Kuuse enamusega puistu seob süsinikku rohkem, kuigi puistute tagavarad on samad.
Arvestades mullahingamisest tulenevat keskmist süsiniku emissiooni (Kukumägi et al. 2011)
on viljakas kasvukohatüübis kasvavad kuuse-kase segapuistud süsinikku akumuleerivad
ökosüsteemid.
The aim of this study was to estimate above-ground biomass and productivity as well as the amount of accumulated carbon in 30-year-old Norway spruce and Silver birch mixed stands in Oxalis site type. The above-ground biomass and production of the stand was estimated by using dimension analysis (model tree method) (Bormann and Gordon 1984; Lõhmus et al. 1996). The above-ground biomasses of the 30-year-old Norway spruce and Silver birch mixed stands growing on fertile site were 163.6 and 145.9 t ha-1 in larger or smaller spruce share, respectively. Main annual production of stem mass was similar in both studied stand varied between 3.8 and 3.9 t ha-1 . Carbon storage in above-ground biomass was different in stands with larger and smaller share of spruce proportion being 10.6 and 8.2 t ha- 1 , respectively. The annual C flux into the soil via litter fall was 1.02 t ha -1 and 1.3 t ha -1 in stands with smaller and larger spruce proportion, respectively. Norway spruce and Silver birch mixed stands are functioning as carbon sink ecosystem. In middle-aged spruce birch mixed stand (30-year-old) 1.02 ha-1 and 1.3 t ha -1 of carbon reached soil through litter in stands with bigger and smaller percentage of spruce accordingly. Based on these results, stands of silver birch are very productive growing in Oxalis site type and Silver birch may exceed the respective values presented in the current yield tables used for Estonian conditions. Current results give additional knowledge about these stands’ development and growth, these results can also be used to model the growth of these stands. Stands with larger share of spruce can accumulate more carbon although both stands’ volume is the same. Given the average carbon emission from soil respiration (Kukumägi et al. 2011), the spruce-birch mixed stands growing in a fertile habitat are carbon-accumulating forest ecosystems.
The aim of this study was to estimate above-ground biomass and productivity as well as the amount of accumulated carbon in 30-year-old Norway spruce and Silver birch mixed stands in Oxalis site type. The above-ground biomass and production of the stand was estimated by using dimension analysis (model tree method) (Bormann and Gordon 1984; Lõhmus et al. 1996). The above-ground biomasses of the 30-year-old Norway spruce and Silver birch mixed stands growing on fertile site were 163.6 and 145.9 t ha-1 in larger or smaller spruce share, respectively. Main annual production of stem mass was similar in both studied stand varied between 3.8 and 3.9 t ha-1 . Carbon storage in above-ground biomass was different in stands with larger and smaller share of spruce proportion being 10.6 and 8.2 t ha- 1 , respectively. The annual C flux into the soil via litter fall was 1.02 t ha -1 and 1.3 t ha -1 in stands with smaller and larger spruce proportion, respectively. Norway spruce and Silver birch mixed stands are functioning as carbon sink ecosystem. In middle-aged spruce birch mixed stand (30-year-old) 1.02 ha-1 and 1.3 t ha -1 of carbon reached soil through litter in stands with bigger and smaller percentage of spruce accordingly. Based on these results, stands of silver birch are very productive growing in Oxalis site type and Silver birch may exceed the respective values presented in the current yield tables used for Estonian conditions. Current results give additional knowledge about these stands’ development and growth, these results can also be used to model the growth of these stands. Stands with larger share of spruce can accumulate more carbon although both stands’ volume is the same. Given the average carbon emission from soil respiration (Kukumägi et al. 2011), the spruce-birch mixed stands growing in a fertile habitat are carbon-accumulating forest ecosystems.
Kirjeldus
Märksõnad
bakalaureusetööd, kuusk, kask, segametsad, biomass, produktsioon, süsinik