Middle Miocene palynoflora of the Legnica lignite deposit complex ...

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habitat had relatively poor representation.
Taxodiaceae-Taxaceae-Cupressaceae occurred
in quantity of a few to 20%, while Alnus,
Liqui dambar, Nyssa, Cyrillaceae/Clethraceae,
and Myrica made up only a few per cent.
Among more mesophilous plants Sequoia,
Betula, Quercus, Fagus, Tricolporopollenites
pseudo cingulum (misidentifi ed by Sadowska
as Rhus), and Juglandaceae prevailed, and
admixture of other trees, shrubs, and not
numerous herbs was observed. According to
Sadowska (1970) this section probably represents
shallow marine coastal zone – beach or
bay (in the upper part of the sandy sediments
vertical roots were present), neighbouring on
forests which produced the above mentioned
pollen grains (Sadowska op. cit.).
Results of the present palynological studies
imply that in the Legnica vicinity the shallow
bay was covered with swamp vegetation. It
was mentioned that in samples from Mużaków
series of the profi le Legnica 33/56 pollen grains
of herbs (mainly grasses max. 70%) are relatively
abundant. In several samples Graminidites
bambusoides was noted (2–5%). In the
other profi le from this deposit (Legnica 47/68)
sum of pollen grains of herbs reached 15%.
It is connected with location of these cores in
marginal zone of the sedimentation basin. The
results of investigations of the Legnica profi les
(mainly Legnica 33/56, as well 47/62) indicate
the existence of plains with shallow water,
and the presence of swamp forests and reed
marshes, composed mainly of grasses, sedges
(Cladium and others), and other herbs. Within
this area of grasses and sedges, in somewhat
drier places, thickets of Myrica and Salix grew.
Swamp forests consisted of Taxodium, Glyptostrobus,
Alnus, and Nyssa, with an admixture
of Salix, Acer, Betula, Myrica, Osmunda, and
bamboos. In comparison with the Lusatian
seam the role of Alnus increased defi nitely. As
the sea has been moving back the role of these
communities and riparian forests became more
signifi cant.
Reed marshes are considered to be an early
stage of succession on the Miocene peat-bogs.
In Legnica 33/56 profi le sample with the highest
proportion of pollen grains of grasses,
accompanied by other herbs (Cyperaceae,
Lythraceae and Theligonumpollenites baculatus),
occurs in the upper part of the Mużaków
series, and directly precedes samples from the
Henryk seam. So, here is well seen early stage
of succession, which yielded this seam. It is
necessary to stress that in the Middle Miocene
sediment pollen grains of grasses are rarely
encountered in such high quantity, and usually
they do not exceed 5% (Tuplice – Sadowska
1977; Gierlachowo, Krosinko, Gołębin
Stary, Ślepuchowo – Ziembińska-Tworzydło
1974). Similar situation is observed in most
of the Legnica profi les (Sadowska et al. 1976,
1981, Sadowska 1977, Nowak 1998, Wacnik
& Worobiec 2001). So, Legnica 33/56 profi le
can advance our understanding the palaeoenvironment
of this area. High percentages of
pollen grains of grasses are more often encountered
above the Henryk seam – Mirostowice
and Gozdnica 40–50% (Sadowska 1977). Reed
marshes are very rarely recorded in the fossil
material, what could be caused by their
features determining weak resistance, or by
features of sediment in which pollen grains
from these communities are found (in Legnica
33/56 borehole there were coaly clays with
large admixture of very fi ne plant remains,
diffi cult to carry out pollen analysis). Nonarboreal
swampy communities were previously
described by Teichmüller (1958) and Neuy-
Stolz (1958) from Germany. From Poland
Kohlman-Adamska (1993) reported high contribution
of Cyperaceae (50%) and Poaceae
(18%) in sample from the Mid-Polish beds of
the Karolewo-Dąbki profi le. At Mirostowice
(upper part of the Mużaków series) relatively
high frequency of Sparganium (17%) was
observed (Sadowska & Zastawniak 1978). Pollen
grains of Graminidites bambusoides were
known from Rypin (Stuchlik 1964), the only
one locality until now.
In the Pawłowice and Adamów beds from
western Poland, in the localities Gierlachowo,
Gołębin Stary, Krosinko, Ślepuchowo, Mosina
(Ziembińska-Tworzydło 1974) pollen grains
of Tsuga (10%) and Sciadopitys (5%) occur
in relatively high quantities, whereas sporomorphs
of thermophilous taxa are not numerous.
Similar situation was observed in profi les
from the Mużaków arch (Tuplice, Mirostowice
– Sadowska 1970, 1977, Sadowska & Zastawniak
1978), as well as the Wyrzysk and Nakło
region (Kohlman-Adamska 1993), whereas in
Legnica profi les pollen grains of both these
genera are somewhat more numerous than
in other sections, but still sparse. This fact
is probably connected with ecology of these
trees and with relief of this region during the