Download presentation
Presentation is loading. Please wait.
Published byJulia Thrall Modified over 10 years ago
1
Supplementary Figure 1. Physical mechanisms in patterned-ground. Frost et al. 2013 – ERL Supp. Figure 1
2
circle inter-circle inter-circle circle circle circle circle Frost et al. 2013 – ERL Supp. Figure 1
3
silt loam blocky blocky organic organic circle inter-circle inter-circle circle circle circle circle Sharp microsite contrasts in soil conditions develop due to differential frost-heave (Taber 1929; Peterson and Krantz 2003) Frost et al. 2013 – ERL Supp. Figure 1
4
Initially, on a barren surface, a more or less hexagonal system of cracks develops due to seasonal freezing. Frost et al. 2013 – ERL Supp. Figure 1
5
Cracks collect seeds and retain moisture, so vegetation and organic matter accumulate there. This creates a strong gradient in soil thermal properties. Frost et al. 2013 – ERL Supp. Figure 1
6
In early winter, downward freezing occurs faster in exposed mineral soils that lack surface organics. Frost et al. 2013 – ERL Supp. Figure 1
7
Increased water flux to circle Pore-water is drawn to the advancing freezing-front in circles due to cryostatic suction. Frost et al. 2013 – ERL Supp. Figure 1
8
Differential frost-heave Increased water-flux leads to stronger frost-heave at circles, as the water expands into ice. Frost et al. 2013 – ERL Supp. Figure 1
9
Cryoturbation is strongest at the circle center. Tundra vegetation grows too slowly to withstand annual disturbance, so circles remain barren. Frost et al. 2013 – ERL Supp. Figure 1
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.