english final - Birbal Sahni Institute of Palaeobotany

BIRBAL SAHNI INSTITUTE OF PALAEOBOTANY
Annual Report 2004-2005
Component 10 : Stable isotope mass spectrometry laboratory for palaeoenvironmental studies
The proposal for establishing a Stable Isotope Ratio
Mass Spectrometry Laboratory has been revised in more cost
effective way. It was proposed that only a sample processing
lab (of Rs. 3-4 lacs) can be set up but no mass spectrometer.
The samples can be processed in this laboratory and can be
analysed in some other laboratory equipped with a mass
spectrometer.
Supriya Chakraborty
Component 11 : Establishment of Palaeobotanical-Geochemical laboratory
The matter to establishment of laboratory has been
initially discussed and subsequently presented before the
Research Advisory Council of the Institute. The RAC
recommended that further action on the issue may not be taken
for the time being.
Anupam Sharma
Emeritus Scientist Project
Project : Lake sediment pollen analytical studies in Rajasthan to
reconstruct the vegetational history and climatic changes since
Last Glacial Maximum (LGM).
Keoladeo National Park (Ghana), Bharatpur— Prepared
the pollen diagram of the pollen analysed 4.4 m deep
profile collected from Ghana. Studies have revealed very
interesting past history of this wetland. According to the local
belief and the available records, the wetland is not more than
300-400 yrs old, but the palynological investigations have
shown that 20,000 yrs ago or may be even beyond a big lake
existed at the site, which today has turned into a shallow
depression. It has also indicated that Bharatpur region had
enough rainfall to feed this big lake. Subsequently, the lake
gradually turned too shallower due to fast silting, lesser rainfall,
climatic change, etc. Studies have also revealed that the earlier
thickly forested (dominated by Holoptelea) scenario has been
changed into the scrub jungles presently seen around the
wetland.
Bharatpur Bird Sanctuary (Ghana)— Pollen analysis
of some samples from another 2.6m deep trench profile from the
same wetland area have yielded good assemblage of pollen/
spores.
Moti Jheel— Pollen analysed 3.35 m deep dug out trench
profile from Moti Jheel situated about 2 km from Ghana wetland
and prepared a pollen diagram. This jheel area is presently under
cultivation. It is revealed that this flat land too was a lake about
6,000 yrs ago and beyond ( 14 C date of 5230+ 460 yrs BP at 3.00
m depth). It was most probably connected with the main Ghana
Lake in the remote past (deeper samples remain to be collected
for pollen analysis). The studies have shown that around 6,000
yrs ago the area was occupied by savannah type vegetation,
represented mainly by Poaceae, Cyperaceae, Chen/Ams,
Urticaceae, Brassicaceae, Holoptelea etc. and it compares well
with the upper part of the Ghana Pollen diagram.
Preliminary pollen analysis of trial samples collected from
Buda Pushkar and Foy Sagar (Ajmer) lake sites have
demonstrated that the profiles are palynologically productive.
Detailed pollen analytical investigations of the two sites can
be undertaken. Preliminary investigations from Sentahl Sagar,
Ramgar Jheel and Chhaparwale Sagar (Jaipur) sites have
revealed poor pollen productivity.
Chhaya Sharma
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