Biological consequences of earlier snowmelt from desert dust deposition in alpine landscapes.
Citation
Thomas H Painter, Christopher C Landry, Edward Ayres, and Heidi Steltzer, Biological consequences of earlier snowmelt from desert dust deposition in alpine landscapes.: .
Summary
Dust deposition to mountain snow cover, which has increased since the late 19(th) century, accelerates the rate of snowmelt by increasing the solar radiation absorbed by the snowpack. Snowmelt occurs earlier, but is decoupled from seasonal warming. Climate warming advances the timing of snowmelt and early season phenological events (e.g., the onset of greening and flowering); however, earlier snowmelt without warmer temperatures may have a different effect on phenology. Here, we report the results of a set of snowmelt manipulations in which radiation-absorbing fabric and the addition and removal of dust from the surface of the snowpack advanced or delayed snowmelt in the alpine tundra. These changes in the timing of snowmelt were superimposed [...]
Summary
Dust deposition to mountain snow cover, which has increased since the
late 19(th) century, accelerates the rate of snowmelt by increasing the
solar radiation absorbed by the snowpack. Snowmelt occurs earlier, but
is decoupled from seasonal warming. Climate warming advances the timing
of snowmelt and early season phenological events (e.g., the onset of
greening and flowering); however, earlier snowmelt without warmer
temperatures may have a different effect on phenology. Here, we report
the results of a set of snowmelt manipulations in which
radiation-absorbing fabric and the addition and removal of dust from the
surface of the snowpack advanced or delayed snowmelt in the alpine
tundra. These changes in the timing of snowmelt were superimposed on a
system where the timing of snowmelt varies with topography and has been
affected by increased dust loading. At the community level, phenology
exhibited a threshold response to the timing of snowmelt. Greening and
flowering were delayed before seasonal warming, after which there was a
linear relationship between the date of snowmelt and the timing of
phenological events. Consequently, the effects of earlier snowmelt on
phenology differed in relation to topography, which resulted in
increasing synchronicity in phenology across the alpine landscape with
increasingly earlier snowmelt. The consequences of earlier snowmelt from
increased dust deposition differ from climate warming and include
delayed phenology, leading to synchronized growth and flowering across
the landscape and the opportunity for altered species interactions,
landscape-scale gene flow via pollination, and nutrient cycling.
Published in Proceedings of the National Academy of Sciences, volume
106, issue 28, on pages 11629 - 34, in 2009.
