1994-95 - Birbal Sahni Institute of Palaeobotany

1994-95
Eight samples of Dangmal prol1le collected from thickets of mangrove forest at
Bhitarkanika, Baitarni Della, Orissa have been palynologically investigated. The samples
showed good assemblage of pollen grains, fungal spores, dinoflagellate cysts, microforaminifera,
Pediastrum, fern spores and Pseudoscltizea. The dominance of Rltizopltora,
Sonneratia, Avicennia, Excoecaria, etc. were recorded. The other peripheral mangroves
and hinterland taxa encountered in varying frequencies are Pandanus, Acacia, Aegialitis,
Heritiera, Xylocarpus, Emblica, Xantltium, Brownlowia, Justicia, Casuarina, Poaceae,
Rubiaceae, Lythraceae, Myrtaceae, Fabaceae, Urticaceae, Chenopodiaceael AmaranUlaceae,
etc. The study reflects the existence of mangrove throve as Ule area enjoyed consistent
marine" incursions.
H.P. Gupta & Asha Khandelwal
Nine samples numbering 166, 180, 184, 194, 197,201,206,208,210,218 from
250 m deep profile fTOmSadanandpur were pollen analysed. The samples are rich both
quantitatively and qualitatively. The important mangrove constituents are represented by
the members of Rhizophoraceae, Avicennia, Sonnera(ia, Excoecaria, Nypa and Brownlowia.
The study has revealed the existence of constant depths of sea water leading to luxuriant
mangrove throve.
H.P. Gupta & R.R. Yadav
Programme 7.4
Objecrive
Dendrochronology of temperate and tropical trees and seasonality
of cambium activity
To recollstruct climate (temperature alld precipitation) from
free rings
To study environmental factors determilling tlte seasonality of
cambium activity
Ring widths of dated tree ring sequences of Abies pindrow collected from Dwali near
Pindari glacier were measured. Tree growth has shown highly individualistic growth pattern
which could be due to inter-tree competition and stand phase disturbances. Tree ring
chronology further needs to be updated with more replication of samples from the area for
climatic reconstluction.
Tree ring samples of teak (Tectona grandis) collected from KOI-Li,Andhra Pradesh
were dated and ling widths measured. A master chronology (1872-1989 AD) was prepared
from nine samples. Tree growth and climate relationship using response function analysis
has shown very good correlation between tree growth and summer precipitation.
Fifteen u·cc core samples of spluce collected from Dodital in Uttarkashi were dated
using Skeleton plot method. Trees have been found 10 be around 300 years in age. Tree core
samples of deodar collected from different areas around Gangotri were also dated. Age of
trees has been found to be around 500 years in Gangotri.
R. R. Yadav & Amalava Bhattacharyya
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