110
3 The Microfloral Assemblages—Their Environmental and Climatic …
hand, were reported by all studies of the Permian-Triassic boundary (Aggarwal et al.
2019; Vajda et al. 2020) due to the extreme atmospheric conditions following intense
volcanism and meteorite impact resulting in the burial and decay of huge amounts
of vegetation.
Disaccate non-taeniate pollen species seem to persist throughout the Permian with
occasional peaks. They represent trees resembling today’s Araucaria and Podocarpus
which thrived and made up the upland flora of those times. Usually disaccate pollen
average about 10%. It is thought that they are the ancestors of today’s conifers such
as Araucaria, Agathis, Podocarpus and others. These were plants that no longer
required growth in or near water. As the climate became warmer they occupied the
mountain sides and have been regarded as ‘Upland Vegetation’ (Chaloner 1958;
Upshaw and Creath 1965). It has been argued from studies of successions of fossil
floras that higher and more specialised type of vegetation was always present in
uplands of a region long before they entered the lowlands as replacement for the
older flora. Suggested reason was the diversity of physical environment in upland
areas which promotes rapid evolution. This may be valid as long as no change in
climate effects the lowlands when the contrary happens: An example for the latter
are the Nothofagus forests of New Guinea which are dying with the general warming
up.
Acritarchs: The importance of acritarchs when in larger than usual concentrations is by signalling a change in the depositional environment, which in turn is a
function of climatic change. There are several peaks of Acritarchs present in the
Artinskian; both in the Lower Artinskian (Biostratigraphic Unit II) and Upper Artinskian (Biostratigraphic Unit III) and several prominent peaks in the upper Permian
(Biostratigraphic Unit IV). Two major peaks of acritarchs are clearly evident in the
Lower Artinskian, biostratigraphic Unit II, and two major ones in the Upper Artinskian (Biostratigraphic Unit III) whereas smaller peaks are spread over the rest of the
Permian sequence. These are markers for flooding of the depositional environment,
lakes forming, drowning of the swamp vegetation and algal domination at times. The
Upper Permian (Biostratigraphic Unit IV) starts with an acritarch peak, followed by
a low. Acritarchs peaked again on and off, with no acritarch presence except two
small peaks towards the end of the Permian, followed by their total absence.
References
Aggarwal N, Aggarwal S, Thakur B (2019) Palynofloral, palynofacies and carbon isotope of
Permian coal deposits from the Godavari Valley Coalfield, South India: Insight into the age,
palaeovegetation and palaeoclimate. Int J Coal Geol (in press)
Anderson JM (1977) The biostratigtraphy of the permian and triassic part 3. A review of Gondwanan
Permian Palynology with particular reference to the Northern Karoo Basin, South Africa. Mem
Bot Surv South Africa 41:1–67
Balme BE (1964) The palynological record of Australian pre-Tertiary floras. In: Cranwell LM (ed)
Ancient pacific floras. Uni Hawaii Press, Honolulu, pp 49–80
3 The Microfloral Assemblages—Their Environmental and Climatic …
hand, were reported by all studies of the Permian-Triassic boundary (Aggarwal et al.
2019; Vajda et al. 2020) due to the extreme atmospheric conditions following intense
volcanism and meteorite impact resulting in the burial and decay of huge amounts
of vegetation.
Disaccate non-taeniate pollen species seem to persist throughout the Permian with
occasional peaks. They represent trees resembling today’s Araucaria and Podocarpus
which thrived and made up the upland flora of those times. Usually disaccate pollen
average about 10%. It is thought that they are the ancestors of today’s conifers such
as Araucaria, Agathis, Podocarpus and others. These were plants that no longer
required growth in or near water. As the climate became warmer they occupied the
mountain sides and have been regarded as ‘Upland Vegetation’ (Chaloner 1958;
Upshaw and Creath 1965). It has been argued from studies of successions of fossil
floras that higher and more specialised type of vegetation was always present in
uplands of a region long before they entered the lowlands as replacement for the
older flora. Suggested reason was the diversity of physical environment in upland
areas which promotes rapid evolution. This may be valid as long as no change in
climate effects the lowlands when the contrary happens: An example for the latter
are the Nothofagus forests of New Guinea which are dying with the general warming
up.
Acritarchs: The importance of acritarchs when in larger than usual concentrations is by signalling a change in the depositional environment, which in turn is a
function of climatic change. There are several peaks of Acritarchs present in the
Artinskian; both in the Lower Artinskian (Biostratigraphic Unit II) and Upper Artinskian (Biostratigraphic Unit III) and several prominent peaks in the upper Permian
(Biostratigraphic Unit IV). Two major peaks of acritarchs are clearly evident in the
Lower Artinskian, biostratigraphic Unit II, and two major ones in the Upper Artinskian (Biostratigraphic Unit III) whereas smaller peaks are spread over the rest of the
Permian sequence. These are markers for flooding of the depositional environment,
lakes forming, drowning of the swamp vegetation and algal domination at times. The
Upper Permian (Biostratigraphic Unit IV) starts with an acritarch peak, followed by
a low. Acritarchs peaked again on and off, with no acritarch presence except two
small peaks towards the end of the Permian, followed by their total absence.
References
Aggarwal N, Aggarwal S, Thakur B (2019) Palynofloral, palynofacies and carbon isotope of
Permian coal deposits from the Godavari Valley Coalfield, South India: Insight into the age,
palaeovegetation and palaeoclimate. Int J Coal Geol (in press)
Anderson JM (1977) The biostratigtraphy of the permian and triassic part 3. A review of Gondwanan
Permian Palynology with particular reference to the Northern Karoo Basin, South Africa. Mem
Bot Surv South Africa 41:1–67
Balme BE (1964) The palynological record of Australian pre-Tertiary floras. In: Cranwell LM (ed)
Ancient pacific floras. Uni Hawaii Press, Honolulu, pp 49–80