The Influence of Tree Islands and Microtopography on Pedoecological Conditions in the Forest-Alpine Tundra Ecotone on Niwot Ridge, Colorado Front Range, U.S.A.

Treelines—Approaches at Different Scales

“…While soils in the treeline ecotone and in the adjacent lower alpine zone (i.e., potential treeline) have developed with the limits set by the general elevational gradients of temperature and precipitation, they vary considerably depending on the local parent material, substrate (physical and chemical properties), vegetation, and on climate history (e.g., [51,[59][60][61][62]). Thus, a locally varying mosaic of soils (soil types) is typical of the treeline ecotone, whereas no real treeline-specific soils exist [5].…”

“…For example, depth, spatial pattern, and duration of the winter snowpack and resultant side effects often must be attributed to trees' feedbacks (e.g., [65,66]). Moreover, compact trees shading the ground reduce soil temperature (e.g., [17,59,66,67]) and, thus, create a cold root zone. However, even age-old trees and suppressed compact krummholz in the treeline ecotone have been growing for many decades, centuries, or even thousands of years and are still producing growth rings, even though shading by the tree canopy has been keeping growing season soil temperature low all the time.…”

Landscape Heterogeneity of Differently Aged Soil Organic Matter Constituents at the Forest–Alpine Tundra Ecotone, Niwot Ridge, Colorado, U.S.A

“…and continues into the subalpine forest (3290 m a.s.l.). The site contains several gradients such as the snow gradient from deep snowfields to dry windblown meadows created by topography and tree islands (Holtmeier and Broll, 1992;Seastedt and Adams, 2001;Walker et al, 2001); the windward and leeward slopes that range from 0 to 22u; and the ridgetop-sideslope-toeslope topography. The site also contains small seasonal wetlands and is drained by several intermittent streams that typically run May through July.…”

Diversity of soil organisms in alpine and arctic soils in Europe. Review an research needs

“…McCOY, 1990), the spatial heterogeneity in mountain areas -especially at the ecotone level-is of importance for soil ecological processes QENNY, 1980;NEUWINGER, 1987;HOLTMEIER & BROLL, 1992;BROLL & HOLTMEIER, 1994;HOLTMEIER, 1994;KEPLIN, 1994;ADAM, 1995;BEDNORZ et al, 1999). A further step in understanding ecological dynamics at the ecosystem and landscape scales (GRABHERR, 1994;HUSTON, 1994;DUELLI, 1995) has already been taken in the Arctic interdisciplinary research conducted in North America (e.g.…”