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POLLEN DIAGRAM

In the pollen diagram arboreal taxa (

AP)

dominate with 70-90% (Fig. 3).

The main forest coniferous and deciduous trees are present -

Pinus diploxylon-

type (

P. mugo

and

P. sylvestris), Pinus рейсе, Picea, Abies, Fagus, Quercus,

Carpinus,

etc. This presumes a realtively young age of the core analysed. The

subdivision of the pollen diagram into two zones (Smr-1 and Smr-2) is based

mainly on the changes in the behaviour of the pollen presence of

Pinus

diploxylon-type, Pinus рейсе, Picea

and

Abies.

At the transition to zone Smr-

2 the quantity of deciduous tree pollen declines.

LPAZ Smr-1 (140-55 cm)

Pollen of

Pinus diploxylon-typQ

prevails with ca 40 %. A slight decrease to

20-25 % is observed for the interval 100-55 cm. Pollen of

Pinus рейсе

shows

a tendency of increase from 10 to 20 %.

Abies

is comparatively well represented

with up to 10 %, together with

Fagus

5-7 % and

Picea

3-5 %. Pollen of

Quercus robur-

type and

Q. cerris-

type reaches 3-5

%.

Low percentages are

recorded for

Corylus, Carpinus, Acer

and

Humulus/Cannabis.

In this zone the

highest frequences of Poaceae up to 20 %,

Artemisia

up to 10 %, Cichoriaceae,

Ranunculus

and

Rumex

pollen are established. Pollen of

Secale

and spores of

Polypodiaceae are also quite common.

The vegetation reconstruction for this zone reveals dominance of communities

of

Pinus mugo

in the subalpine zone, and wide distribution of mixed coniferous

forests with

Pinus рейсе, Pinus sylvestris

and

Picea abies

on the northern

approaches to the lake. The find of

Fagus

pollen demonstrates its good

capacity of upslope transport from mid-altitudes and testifies to the wider past

distribution of

Fagus

in the vicinity of the Rila Monastery, an area where the

best preserved old beech forests in this part of the mountain are found

nowadays. Silver fir

{Abies alba

) has occupied the lower part of the coniferous

belt. Nowadays vast monodominant or mixed communities of

Abies alba

are

growing in the valley of the Rilska Reka river at 1400-1600 m. At low altitudes

the tree vegetation was represented by mixed oak forests.

In general, the herb pollen types identified

{NAP),

reflect the vegetation

pattern around the sampling site by that time, being composed of various

representatives of Poaceae, Asteraceae, Brassicaceae, Ranunculaceae and

Caryophyllaceae species. The regular presence of pollen of anthropogenic

indicators

{Plantago lanceolata, Rumex, Scleranthus)

and of cereals

{Secale)

is

indicative of well-pronounced human interference, seasonal livestock-breeding

on the high pasture land and crop production in the foothills.

The time interval for this zone is determined by comparison with the pollen

diagram from the near-by Lake Ostrezko-2 ( То п к о v, M a r i n o v a , in press).

In particular, the decline of

Abies

and the rise of

Picea

in Lake Osrezko-2 were

dated at 1290+/-40 yrs. В. P. This age can be also accepted for the zone

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