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| Titel |
Grazing by reindeer in subarctic coniferous forests -- how it is affecting
three main greenhouse gas emissions from soils. |
| VerfasserIn |
Kajar Köster, Egle Köster, Frank Berninger, Jukka Pumpanen |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250147845
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| Publikation (Nr.) |
 EGU/EGU2017-12058.pdf |
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| Zusammenfassung |
| Reindeer (Rangifer tarandus L.) are the most important large mammalian herbivores in the
northern ecosystems, strongly affecting Arctic lichen dominated ecosystems. Changes caused
by reindeer in vegetation have indirect effects on physical features of the soil e.g. soil
microclimate, root biomass and also on soil carbon dynamics, and little is known about
reindeer and their impact on greenhouse gas (GHG) emissions between the soil and
atmosphere.
In a field experiment in northern boreal subarctic coniferous forests in Finnish Lapland,
we investigated the influence of reindeer grazing on soil GHG (CO2, CH4 and N2O) fluxes,
ground vegetation coverage and biomass, soil temperature and water content. The study was
carried out in the growing season of the year 2014. We established the experiment as a
split plot experiment with 2 blocks and 5 sub-plots per treatment that were divided
into grazed and non-grazed parts, separated with a fence. The sample plots are
located along the borderline between Finland and Russia, where the non-grazed area
was excluded from reindeer already in 1918, to prevent the Finnish reindeer from
going to the Russian side and there are not many reindeer on Russian side of the
area.
Our study showed that grazing by reindeer significantly affected lichen and moss
biomasses. Lichen biomass was significantly lower in the grazed. We also observed that when
lichens were removed, mosses were quickly overtaking the areas and moss biomass was
significantly higher in grazed areas compared to non-grazed areas. Our results indicated
that grazing by reindeer in the northern boreal subarctic forests affects the GHG
emissions from the forest floor and these emissions largely depend on changes in
vegetation composition. Soil was always a source of CO2in our study, and soil CO2
emissions were significantly smaller in non-grazed areas compared to grazed areas.
The soils in our study areas were CH4 sinks through entire measurement period,
and grazed areas consumed more CH4 compared to non-grazed areas. We also
observed that the N2O emissions were significantly affected by moss biomass and soil
temperature. Non-grazed areas with lower moss biomass and soil temperature were a
small sink of N2O while the total fluxes remained around zero in the grazed areas. |
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