Net Primary Production and Carbon Stocks for Subarctic Mesic-Dry Tundras with Contrasting Microtopography, Altitude, and Dominant Species

TY - JOUR

T1 - Net Primary Production and Carbon Stocks for Subarctic Mesic-Dry Tundras with Contrasting Microtopography, Altitude, and Dominant Species

AU - Campioli, Matteo

AU - Michelsen, Anders

AU - Demey, A

AU - Vermeulen, Annemie

AU - Samson, R

AU - Lemeur, R

N1 - Keywords heath - seasonal plant growth - annual production - vegetation biomass - carbon and nitrogen stocks - ecosystem C cycling - northern Sweden

PY - 2009

Y1 - 2009

N2 - Mesic-dry tundras are widespread in the Arctic but detailed assessments of net primary production (NPP) and ecosystem carbon (C) stocks are lacking. We addressed this lack of knowledge by determining the seasonal dynamics of aboveground vascular NPP, annual NPP, and whole-ecosystem C stocks in five mesic-dry tundras in Northern Sweden with contrasting microtopography, altitude, and dominant species. Those measurements were paralleled by the stock assessments of nitrogen (N), the limiting nutrient. The vascular production was determined by harvest or in situ growing units, whereas the nonvascular production was obtained from average species growth rates, previously assessed at the sites. Results showed that aboveground vascular NPP (15-270 g m-2), annual NPP (214-282 g m-2 or 102-137 g C m-2) and vegetation biomass (330-2450 g m-2) varied greatly among communities. Vegetation dominated by Empetrum hermaphroditum is more productive than Cassiope tetragona vegetation. Although the large majority of the apical NPP occurred in early-mid season (85%), production of stems and evergreen leaves proceeded until about 2 weeks before senescence. Most of the vascular vegetation was belowground (80%), whereas most of the vegetation production occurred aboveground (85%). Ecosystem C and N stocks were 2100-8200 g C m-2 and 80-330 g N m-2, respectively, stored mainly in the soil turf and in the fine organic soil. Such stocks are comparable to the C and N stocks of moister tundra types, such as tussock tundra.

AB - Mesic-dry tundras are widespread in the Arctic but detailed assessments of net primary production (NPP) and ecosystem carbon (C) stocks are lacking. We addressed this lack of knowledge by determining the seasonal dynamics of aboveground vascular NPP, annual NPP, and whole-ecosystem C stocks in five mesic-dry tundras in Northern Sweden with contrasting microtopography, altitude, and dominant species. Those measurements were paralleled by the stock assessments of nitrogen (N), the limiting nutrient. The vascular production was determined by harvest or in situ growing units, whereas the nonvascular production was obtained from average species growth rates, previously assessed at the sites. Results showed that aboveground vascular NPP (15-270 g m-2), annual NPP (214-282 g m-2 or 102-137 g C m-2) and vegetation biomass (330-2450 g m-2) varied greatly among communities. Vegetation dominated by Empetrum hermaphroditum is more productive than Cassiope tetragona vegetation. Although the large majority of the apical NPP occurred in early-mid season (85%), production of stems and evergreen leaves proceeded until about 2 weeks before senescence. Most of the vascular vegetation was belowground (80%), whereas most of the vegetation production occurred aboveground (85%). Ecosystem C and N stocks were 2100-8200 g C m-2 and 80-330 g N m-2, respectively, stored mainly in the soil turf and in the fine organic soil. Such stocks are comparable to the C and N stocks of moister tundra types, such as tussock tundra.

KW - Faculty of Science

KW - planter

KW - arktis

KW - økologi

KW - kulstof

KW - plants

KW - arctic

KW - ecology

KW - carbon

U2 - 10.1007/s10021-009-9255-3

DO - 10.1007/s10021-009-9255-3

M3 - Journal article

SN - 1432-9840

VL - 12

SP - 760

EP - 776

JO - Ecosystems

JF - Ecosystems

IS - 5

ER -