TY  - JOUR
A1  - Prasad, Sushma
A1  - Mishra, Praveen Kumar
A1  - Menzel, Philip
A1  - Gaye, Birgit
A1  - Jehangir, Arshid
A1  - Yousuf, Abdul R.
T1  - Testing the validity of productivity proxy indicators in high altitude Tso Moriri Lake, NW Himalaya (India)
JF  - Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences
N2  - We use multiple proxies (delta C-13(org), delta N-15(org), C/N, amino acids, biogenic silica) from the catchment, lake surface and core sediments to (i) identify the factors influencing conventional lacustrine primary productivity (LPP) indicators (isotopic covariance, C/N) in the sediments from the pristine high altitude Tso Moriri Lake during the late Quaternary, (ii) compare C/N and bulk organic isotopic data from the core with available biogenic silica and amino acid data to test the applicability of conventional LPP indicators during the late Quaternary, and (iii) evaluate the degree of sensitivity of LPP to climate change. Our results show that climate driven changes in water salinity and source water changes have influenced the isotopic (delta C-13, delta N-15) content of the lake water and hence the isotopic composition of bulk organic matter. Erosion has also played a role in masking the LPP as the catchment sediments from this high altitude lake have low C/N thereby casting doubt on the effectiveness of this parameter as an LPP indicator. Independent LPP indicators in Tso Moriri sediments clearly indicate that it is driven by climate change and increases during warmer periods. However, our data show that the LPP in recent times is not much higher than during the early Holocene, ruling out any impact of recent warming on LPP and therefore the possibility of large carbon sequestration in high altitude oligotrophic lakes. (C) 2016 Elsevier B.V. All rights reserved.
KW  - Tso Moriri Lake
KW  - isotopes
KW  - lacustrine primary productivity (LPP)
KW  - Indian monsoon
KW  - late Quaternary
Y1  - 2016
U6  - https://doi.org/10.1016/j.palaeo.2016.02.027
SN  - 0031-0182
SN  - 1872-616X
VL  - 449
SP  - 421
EP  - 430
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Basavaiah, Nathani
A1  - Wiesner, M. G.
A1  - Anoop, Ambili
A1  - Menzel, P.
A1  - Nowaczyk, Norbert R.
A1  - Deenadayalan, K.
A1  - Brauer, Achim
A1  - Gaye, Birgit
A1  - Naumann, R.
A1  - Riedel, N.
A1  - Stebich, M.
A1  - Prasad, Sushma
T1  - Physicochemical analyses of surface sediments from the Lonar Lake, central India - implications for palaeoenvironmental reconstruction
JF  - Fundamental and applied limnology : official journal of the International Association of Theoretical and Applied Limnology
N2  - We report the results of our investigations on the catchment area, surface sediments, and hydrology of the monsoonal Lonar Lake, central India. Our results indicate that the lake is currently stratified with an anoxic bottom layer, and there is a spatial heterogeneity in the sensitivity of sediment parameters to different environmental processes. In the shallow (0-5 m) near shore oxic-suboxic environments the lithogenic and terrestrial organic content is high and spatially variable, and the organics show degradation in the oxic part. Due to aerial exposure resulting from lake level changes of at least 3m, the evaporitic carbonates are not completely preserved. In the deep water (>5 m) anoxic environment the lithogenics are uniformly distributed and the delta C-13 is an indicator not only for aquatic vs. terrestrial plants but also of lake pH and salinity. The isotopic composition of the evaporites is dependent not only on the isotopic composition of source water (monsoon rainfall and stream inflow) and evaporation, but is also influenced by proximity to the isotopically depleted stream inflow. We conclude that in the deep water environment lithogenic content, and isotopic composition of organic matter can be used for palaeoenvironmental reconstruction.
KW  - isotopes
KW  - lonar lake
KW  - modern surface sediments
KW  - magnetic parameters
KW  - monsoon
KW  - palaeoenvironmental proxies
Y1  - 2014
U6  - https://doi.org/10.1127/1863-9135/2014/0515
SN  - 1863-9135
VL  - 184
IS  - 1
SP  - 51
EP  - 68
PB  - Schweizerbart
CY  - Stuttgart
ER  -