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in the arctic tundra is an integrator of biological, geochemical, physical, and
anthropogenic processes and interactions. These processes correlate with regional
and global climate system that mainly depends on biogeochemical cycles of carbon
and methane. Approximately 25 % of the world
is soil organic carbon reservoir is
stored at high northern latitudes in permafrost and seasonally-thawed soils in the
Arctic. Knowledge of carbon cycle in the arctic tundra and understanding of its
dependence on the biological and ecological processes has globally signi
'
cant
implication for the study of non-linear potentially positive feedback response of
arctic climate on the very quickly change of arctic terrestrial ecosystems.
The nature of the interactions among climate, permafrost, hydrology, and arctic
ecosystems was the topic of a
“
Biocomplexity, Hydrology and Frozen Ground in
Cold Regions
session at the 2006 Fall Meeting of the American Geophysical Union
(AGU) where problems of arctic tundra investigations refer in part to understanding:
”
the nonlinear response of arctic systems to perturbations;
the magnitude and extent of positive and negative feedback processes involved
in such key processes as heat, CO
2
, and water vapor exchange between the
biosphere and the atmosphere;
the dynamics of self organization in processes governing patterned-ground
formation; and
the high degree of interdisciplinary research required to understand the inter-
actions of biological, physical, and chemical processes in these systems.
Biocomplexity of the arctic tundra ecosystem is determined by coopled con-
sideration of interactions between plants, animals and environment. Arctic plants
include: arctic moss, arctic willow, bearberry, carbon moss, diamond-leaf willow,
labrador tea, pasque
flower, tufted saxifrage, reindeer moss, dwarf birch, woodland
geranium, arctic fowl-grass, kelp, lichen centraria. Arctic animals include: arctic
fox, caribou, ermine, grizzly bear, harlequin duck, musk ox, polar bear, walrus,
habitual seal, lemming, northern deer, pink gull, guillemot. Arctic animals migrate
during year depending on the seasonal dynamics of living conditions. Total
dynamic assessment of the biocomplexity of arctic tundra ecosystem can be realized
by the realization of modelling technology for the parameterization of energetic
relations between its components. Figures
6.18
and
6.19
gives the principal
schemes for possible model realizations. Model that realizes the diagram of
Fig.
6.18
, demonstrates dual nutrient controls across trophic levels and its bio-
geochemical signi
fl
cance. Figure
6.19
characterizes trophic interactions between
the tundra plants and some living components of the arctic ecosystem.
Biocomplexity
(t) of the tundra ecosystem has a seasonal character, changing,
depending on the migration regime and climate that is characterized by low tem-
peratures during practically all year. Average temperature of the most warm month
(July or August) in the tundra is 10
ʾ
°
C. The vegetation reanimation is observed
when the summer comes and solar radiation is available. Life processes in the
tundra is continued during winter period only in the lakes and marshes, as well as
partly in soils. Figure
6.20
shows typical distribution of the biocomplexity in the
arctic tundra calculated for meteorological conditions averaged for 2000
-
15
2013.
-
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