Trade-offs Between Wood and Leaf Production in Arctic Shrubs Along a Temperature and Moisture Gradient in West Greenland
- PDF / 1,166,192 Bytes
- 15 Pages / 593.972 x 792 pts Page_size
- 34 Downloads / 145 Views
Trade-offs Between Wood and Leaf Production in Arctic Shrubs Along a Temperature and Moisture Gradient in West Greenland Rebecca Finger Higgens,1*
Caitlin Hicks Pries,1,2 and Ross A. Virginia1,3
1
Ecology, Evolution, Environment and Society Graduate Program, Dartmouth College, Hanover, NH, USA; 2Department of Biological Science, Dartmouth College, Hanover, NH, USA; 3Environmental Studies Program, Dartmouth College, Hanover, NH, USA
ABSTRACT Warming environmental conditions are often credited with increasing Arctic shrub growth and altering abundance and distribution, yet it is unclear whether tundra shrub expansion will continue into future decades. Water availability may begin to limit Arctic shrub growth if increasing air temperatures create drier soil conditions due to increased evapotranspiration and permafrost-thawinduced soil drainage. However, few studies have effectively considered how dominant tundra shrub species respond to variations in both temperature and moisture. To better understand the key effects of temperature variation and soil moisture on two dominant circumpolar deciduous shrubs, we studied shrub growth along a natural landscape gradient in West Greenland, which is a region observed to be drying due to ongoing warming. We found that the growth forms of both grey willow (Salix glauca) and dwarf birch (Betula nana) were sensitive
Received 19 May 2020; accepted 25 July 2020 Electronic supplementary material: The online version of this article (https://doi.org/10.1007/s10021-020-00541-4) contains supplementary material, which is available to authorized users. Author contributions: RFH conceived of and designed study, performed research, analyzed data, and wrote the paper; CHP helped with data analysis and writing the paper; RAV helped with research and writing the paper. Data from this study are archived with the Arctic Data Center. https://arcticdata.io/catalog/view/urn:uuid:3c55fe83-77a8-46318f03-62f49eced59d. *Corresponding author; e-mail: [email protected]
to warmer and drier conditions. For both species, increases in air temperature positively correlated with greater shrub volume, with the doubling of canopy volume due to increased woody biomass. Leaf biomass was best predicted by edaphic features including extractable ammonium, which was positively related to soil moisture, and bulk density. Warmer soils tended to be drier, suggesting that ongoing warming in the area could lead to significant water limitation. Our findings suggest that drier soil conditions might be limiting foliar production despite warming temperatures for two circumpolar dominant shrubs, Betula nana and Salix glauca, which could have wide-ranging, biome-level consequences about ongoing and predicted shrub growth and expansion. Key words: Arctic; shrub; growth forms; soil moisture; trade-offs; plant traits; Greenland.
R. F. Higgens and others
HIGHLIGHTS Water limitations may constrain Arctic shrub growth as air temperatures continue to rise Using a landscape gradient, we studied how temperature and mois
Data Loading...
