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Land-Ocean Systems in the Siberian Arctic: Dynamics and History
dwarf shrub-moss spotty mountain tundra with 20-40 % cover (Salix arctica, Dryas punctata,
Carex rupestris, Papaver polare, Oxytropis nigrescens; the forb and grasses are various; in the
moss layer: Hylocomium splendens var. Obtusifolium). The soils are Dystri-gelic Regosols and
Eutri-gelic Leptosols; in depressions the turf horizon is better developed.
4 - Structurally denudated mountain ridges with flat and inclined surfaces and patterned ground,
which is defined by cryogenic weathering (rings of fine-grained soil) and boulder debris on the
ledges of ridges
These features are composed mainly of dolerites and are distributed at all hypsometric levels.
Their vegetation, however, varies depending on elevation. The boulder debris of the lower
mountain belt (A) differs by having a rather specific petrophilous vegetation. The boulder
slopes have a mesic herb-cassiope-moss vegetation with 40-60 % cover (Cassiope tetragona,
Saxifraga hyperborea, Dryopteris fragrans, Rhodiola rosea; in moss layer Hylocomium
splendens var. obtusifolium dominates). The soils are Regosols and have developed in the
cracks between boulders. In protected locations, which receive more snow in winter, small
mountain mesic short grass meadows with Potentilla nivea subsp. mischkinii, Arnica iljinii,
Saussurea tilesii et al. on Eutri-gelic Regosols are found. For similar features of the upper
mountain belt (B) (but also on heavily snowed portions of the lower belt) lichens alone, with 520 % cover, are found. On the western half of the central lake basin, the surfaces of the ridges
are flat (C), with sparse (5-7 % cover) petrophilus forbs (Novosieversia glacialis, Luzula
nivalis, Saxifraga caespitosa et al.) on Dystri-gelic Regosols.
5 - Prominent surfaces and plateaus, composed of limestones with rock outcrops and angles of
inclination from 0 up to 10°
They have a very complicated relief. We consider them as a complex, consisting of 5 elements
of relief mesoform, with specific calciphilous vegetation types. These relatively low (\90-270
m a.s.!.) limestone mountains lie in the northern and north-eastern portion of the lake basin.
The elements of the complex herein provided are usually grouped in one uniform ecological
series: A) Rock outcrops with a very sparse (not more than \-2 %) cover of crustaceous lichens
and petrophilous forbs (Papaver leucotrichum, Draba cinerea, D. macrocarpa et al.) on Littic
Loptoso!. In rock cracks advanced Calcari-gelic Regosols develop. B) The structural mountain
deserts with sparse lichens cover (Thamnolia sp.) and slightly greater vascular plant cover
(Braya purpurascens, Taraxacum phymatocarpum, Cardamine bellidifolia). The cover is not
more than \ % and exposed locations are practically lifeless. There is no soil cover. C) Flatter
and lower exposures than the previous landscape type, with patterned ground. These regions
are occupied by dry willow-moss-forb tundra (Salix arctica, Braya purpurascens, Poa arctica,
Oxygraphis glacialis; in fragmented moss layers, Rhacomitrium lanuginosum dominated).
Cover is \-10 % and the soils are Galcari-gelic Regosols. D) Stone-striped slopes with spottyhummocks; herb-dryas tundra (Dryas punctata, Carex rupestris, Astragalus tolmaczewii,
Oxytropis putoranica, Eritrichium sericeum subsp.arctisibiricum et at.); vegetative cover up to
30 %; the soils are Rendzi-gelic Leptosols. E) Feet of stone-striped slopes, moist, with mosssedge and sedge-moss vegetation (Carex redowskiana, C. atrofusca, Equisetum variegatum,
funcus castaneus; mosses: Tomentypnum nitens, Orthothecium chryseon; cover up to 60 %)
on Rendfi-gelic Leptosols. Moist nival short grass meadows with Oxygraphis glacialis,
Minuartia stricta, Stellaria crassipes et al develop near snow fields.
Land-Ocean Systems in the Siberian Arctic: Dynamics and History
dwarf shrub-moss spotty mountain tundra with 20-40 % cover (Salix arctica, Dryas punctata,
Carex rupestris, Papaver polare, Oxytropis nigrescens; the forb and grasses are various; in the
moss layer: Hylocomium splendens var. Obtusifolium). The soils are Dystri-gelic Regosols and
Eutri-gelic Leptosols; in depressions the turf horizon is better developed.
4 - Structurally denudated mountain ridges with flat and inclined surfaces and patterned ground,
which is defined by cryogenic weathering (rings of fine-grained soil) and boulder debris on the
ledges of ridges
These features are composed mainly of dolerites and are distributed at all hypsometric levels.
Their vegetation, however, varies depending on elevation. The boulder debris of the lower
mountain belt (A) differs by having a rather specific petrophilous vegetation. The boulder
slopes have a mesic herb-cassiope-moss vegetation with 40-60 % cover (Cassiope tetragona,
Saxifraga hyperborea, Dryopteris fragrans, Rhodiola rosea; in moss layer Hylocomium
splendens var. obtusifolium dominates). The soils are Regosols and have developed in the
cracks between boulders. In protected locations, which receive more snow in winter, small
mountain mesic short grass meadows with Potentilla nivea subsp. mischkinii, Arnica iljinii,
Saussurea tilesii et al. on Eutri-gelic Regosols are found. For similar features of the upper
mountain belt (B) (but also on heavily snowed portions of the lower belt) lichens alone, with 520 % cover, are found. On the western half of the central lake basin, the surfaces of the ridges
are flat (C), with sparse (5-7 % cover) petrophilus forbs (Novosieversia glacialis, Luzula
nivalis, Saxifraga caespitosa et al.) on Dystri-gelic Regosols.
5 - Prominent surfaces and plateaus, composed of limestones with rock outcrops and angles of
inclination from 0 up to 10°
They have a very complicated relief. We consider them as a complex, consisting of 5 elements
of relief mesoform, with specific calciphilous vegetation types. These relatively low (\90-270
m a.s.!.) limestone mountains lie in the northern and north-eastern portion of the lake basin.
The elements of the complex herein provided are usually grouped in one uniform ecological
series: A) Rock outcrops with a very sparse (not more than \-2 %) cover of crustaceous lichens
and petrophilous forbs (Papaver leucotrichum, Draba cinerea, D. macrocarpa et al.) on Littic
Loptoso!. In rock cracks advanced Calcari-gelic Regosols develop. B) The structural mountain
deserts with sparse lichens cover (Thamnolia sp.) and slightly greater vascular plant cover
(Braya purpurascens, Taraxacum phymatocarpum, Cardamine bellidifolia). The cover is not
more than \ % and exposed locations are practically lifeless. There is no soil cover. C) Flatter
and lower exposures than the previous landscape type, with patterned ground. These regions
are occupied by dry willow-moss-forb tundra (Salix arctica, Braya purpurascens, Poa arctica,
Oxygraphis glacialis; in fragmented moss layers, Rhacomitrium lanuginosum dominated).
Cover is \-10 % and the soils are Galcari-gelic Regosols. D) Stone-striped slopes with spottyhummocks; herb-dryas tundra (Dryas punctata, Carex rupestris, Astragalus tolmaczewii,
Oxytropis putoranica, Eritrichium sericeum subsp.arctisibiricum et at.); vegetative cover up to
30 %; the soils are Rendzi-gelic Leptosols. E) Feet of stone-striped slopes, moist, with mosssedge and sedge-moss vegetation (Carex redowskiana, C. atrofusca, Equisetum variegatum,
funcus castaneus; mosses: Tomentypnum nitens, Orthothecium chryseon; cover up to 60 %)
on Rendfi-gelic Leptosols. Moist nival short grass meadows with Oxygraphis glacialis,
Minuartia stricta, Stellaria crassipes et al develop near snow fields.