Field trips

Field Trip A

PRISTINE AND DISTURBED SITES OF THE GREAT VASYUGAN MIRE

2-3 October 2021

Route and schedule

Excursion Day 1 – Saturday, 2 October

Bus transfer from Tomsk to a field site in Bakchar district of Tomsk region. Distance from Tomsk is 230 km, travel time is about 2.5-3 hours.

Walking tour 1 to drained and partially burned in 2016 part of Bakchar Bog (north-east part of the Great Vasyugan mire)

Route length is about 13 km.

Walking tour 1 include the visit of

• Drained pine dwarf-shrub sphagnum bog
• Completely and partially burned in 2016 sites of pine dwarf shrub-sphagnum bog
• Ridge-hollows and ridge-pool complex

Bus transfer to Bakcharvillage

Staying in a hotel in Bakchar village

Excursion Day 2 – Sunday, 3 October

BustransferfromBakcharvillage to Polynyanka village. Distance from Bakchar village is 30 km, travel time is about 30 minutes

Walking tour 2 to pristine site of Bakchar Bog

Route length is about 15 km.

Walking tour 1 include the visit of

• Swamp forest with birch, aspen, Siberian cedar, and spruce in the margin part of the mire
• Pine dwarf-shrub sphagnum, pine-shrub sedge-sphagnum bogs
• Ridge-hollows and ridge-pool complex

Bus transfer to Tomsk

Pristine landscapes of Bakchar bog

Bakchar bog is located within the southeast West Siberian plain in the interfluve of the Bakchar River and the Iksa River (Middle Ob River watershed). The area of Bakchar bog is about 2600 km2. The territory belongs biogeographically to the southern taiga zone. The quaternary deposits are represented by fluviolacustrine loams and clays. The thickness of the quaternary deposits on the interfluve of the Bakchar River and the Iksa River reaches 40-60 m. The climate is continental with long, cold winters and short, hot summers; the average annual temperature is 0.23°C. The annual amount of precipitation is 473 mm according to the meteorological station near the Bakcharvillage. The average annual evapotranspiration reaches 332 mm. Positive atmospheric water balances, flat relief, and weak drain ability by rivers allows the formation and sustainable evolution of mires. Large mire massifs are widely distributed within the study area. Change of the mire microlandscapes comes from the swamp forest in the margins to the ridge-hollows and ridge-pool complex in the centre. The walking tour includes the visits of typical Western Siberia ridge-hollows and ridge-pool complex,pine-shrub-sphagnum, pine-shrub sedge-sphagnum ombrotrophic mires, and swamp forest with birch, aspen, Siberian cedar, and spruce in the margin part of the mire. The vegetation of the complex mire is dominated by Pinus silvestris, Chamaedaphne calyculata, Ledum palustre, Andromeda polifolia and Sphagnum fuscum on the ridge and Scheuchzeria palustris, Sphagnum angustifolium in hollows. The vegetation of the pine-shrub-sphagnum mire is dominated by Pinus silvestris, Chamaedaphne calyculata, Ledum palustre, Sphagnum fuscum, Sphagnum magellanicum. The pine-shrub sedge-sphagnum mire is occupied by Pinus silvestris, Betula pubescens, Pinus sibirica, Ledum palustre, Chamaedaphne calyculata, Carex rostrata, Eriophorum vaginatum, and Sphagnum angustifolium. The ombrotrophic mire is surrounded by a swamp forest dominated by Pinus sibirica, Betula pubescens, Picea obovata, Populustremula, Rosa acicularis, Ledum palustre, Carex cespitosa, Calla palustris, Menyantes trifoliata, Sphagnum angustifolium, and Bryidae.

Land-use history and current state of Backchar bog

Bakchar bog was drained over an area of77 km2for forestry in the 1980s. The distance between the drainage channels is 150-160 m, the planned width is 1-2 m, and the depth is up to 1 m. At present, there is a decrease in the culvert capacity of the channels due to their overgrowing and hoarding. The part of drained bog and the adjacent forest was burned out in the period of August–October 2016. The most intense burning occurred in the period of August 11–18, 2016 when 80% of the area was exposed to fire mainly within the drained pine-dwarf shrub-sphagnum bog. The burning of forest occurred in October 2016. The area of fire spread was 5.54 km2, including 4.44 km2 within the mire. The spread of fire in the eastern and northeastern parts was limited by the main channels, in the south by the boundary of the drainage network, and in the north by the road. The central part of the allocated area was not subject to pyrogenic load, the contour of which coincides with the boundary of moister hummock-hollow and grass-moss mire areas. The complete burned site of pine- dwarf shrub-sphagnum bog is characterized by charred of trees trunks and crowns of trees and widespread burning of the ground part of dwarf shrubs and mosses. The projective cover of grass-dwarf shrub layer increased to 40% three years after the fire due to vegetative regeneration of the surviving shoots buried underground in the peat. Renewal of the tree layer (Betula pubescence and Populus tremula) was noted by the end of the second growing season, and in the third year reached 5%. A year after the fire, a single appearance of Polytrichum striatum were noted, three years after fire their projective cover increased to 20%.

Field Trip B

SAMUS LAKE AND MIRE COMPLEX

7 October 2021

Route and schedule

from Tomsk to field site near Samusvillage in Tomsk district of Tomsk region. Distance from Tomsk is 50 km, travel time is about 1 hour

Walking tour to Samus lake and mire complex

Route length is about 6 km.

Walking tour 1 include the visit of

• Pine forest
• Pine dwarf-shrub sphagnum bog
• Pine-moss bog near the shore of the Yakovo lake

Bus transfer to Tomsk

Landscapes of Samus lake and mire complex

The territory is located within the second floodplain terrace of the Tom River in the southern taiga subzone of Western Siberia. The Samuslake complex is represented by seven lakes that are connected in a single hydrological system. The largest of these are Yakovo, Krugloe, Maltsevo.

Pine dwarf-shrub sphagnum bogs massifs of rounded shape are predominant among the mires. It is occupying relief depressions among dry pine forests. The vegetation cover is dominated by Pinus sylvestris, Chamaedaphne calyculata, Sphagnum fuscum and Sphagnum magellanicum. The marginal parts of pine dwarf-shrub sphagnum bogs are often waterlogged due to water runoff both from the centre of the raised bogs and from adjacent forests.