Amino acid data of catchment and sediment core samples of four Indian lakes

In the present study, we report the results of comprehensive amino acid (AA) analyses of four Indian lakes from different climate regimes. We focus on the investigation of sediment cores retrieved from the lakes but data of modern sediment as well as vascular plant, soil, and suspended particulate matter samples from individual lakes are also presented. Commonly used degradation and organic matter source indices are tested for their applicability to the lake sediments, and we discuss potential reasons for possible limitations. A principal component analysis including the monomeric AA composition of organic matter of all analysed samples indicates that differences in organic matter sources and the environmental properties of the individual lakes are responsible for the major variability in monomeric AA distribution of the different samples. However, the PCA also gives a factor that most probably separates the samples according to their state of organic matter degradation. Using the factor loadings of the individual AA monomers, we calculate a lake sediment degradation index (LI) that might be applicable to other palaeo-lake investigations.

Aerosol total mass concentration and optical depth during IPY 2007-2008 at Maitri and Larsemann Hills Station

The properties of background aerosols and their dependence on meteorological, geographical and human influence are examined using measured spectral aerosol optical depth (AOD), total mass concentration (Mt) and derived number size distribution (NSD) over two distinct coastal locations of Antarctica; Maitri (70°S, 12°E, 123 m m.s.l.) and Larsemann Hills (LH; 69°S, 77°E, 48 m m.s.l.) during southern hemispheric summer of 2007-2008 as a part of the 27th Indian Scientific Expedition to Antarctica (ISEA) during International Polar Year (IPY). Our investigations showed comparable values for the mean columnar AOD at 500 nm over Maitri (0.034±0.005) and LH (0.032±0.006) indicating good spatial homogeneity in the columnar aerosol properties over the coastal Antarctica. Estimation of Angstrom exponent a showed accumulation mode dominance at Maitri (alpha ~1.2±0.3) and coarse mode dominance at LH (0.7±0.2). On the other hand, mass concentration (M(T)) of ambient aerosols showed relatively high values (~8.25±2.87 µg/m**3) at Maitri in comparison to LH (6.03±1.33 µg/m**3).

Discarge compilation from The Global River Discharge (RivDIS) Project

The Global River Discharge (RivDIS) data set contains monthly discharge measurements for 1018 stations located throughout the world. The period of record varies widely from station to station, with a mean of 21.5 years. These data were digitized from published UNESCO archives by Charles Voromarty, Balaze Fekete, and B.A. Tucker of the Complex Systems Research Center (CSRC) at the University of New Hampshire. River discharge is typically measured through the use of a rating curve that relates local water level height to discharge. This rating curve is used to estimate discharge from the observed water level. The rating curves are periodically rechecked and recalibrated through on-site measurement of discharge and river stage.

Mineralogy of northern Indian Ocean surface sediments and of suspended sediments of Indian rivers (Table 2 and 5)

The solid phases from surface sediments, atmospheric dusts, and rivers of the Indian Ocean environment have been analyzed for their clay minerals and quartz. Such data have been used to delimit the transport paths and sources of the detrital minerals in the oceanic deposits. Diagnostic in distinguishing fluvial and eolian inputs to the northern Indian Ocean is a combination of the clay mineral assemblages and of their geographic distributions. River borne solids are the primary components of the Bay of Bengal deposits. The eastern part receives its continental input through the Ganges-Brahmaputra river system, while drainage of the Indian Peninsula by rivers introduces solids to the western part. The former materials are characterized by high illite and chlorite in the clay mineral assemblages; the latter by montmorillonite. The winds over the Bay bear distinctive dust burdens based upon their directions. However, their contributions to the sediments are insignificant. The eastern sector of the Arabian Sea receives major contributions of continental debris from the rivers and the high montmorillonite levels clearly indicate a source in the Indian Peninsula. The rest of the Sea appears to receive most of its land-derived materials from the north, perhaps the desert regions of northern India and West Pakistan, and they are wind-borne. These materials are also transported to the equatorial regions of the Indian Ocean. A gradient in attapulgite, just north of the equator, may indicate an eolian contribution to the Arabian Sea from the African continent. The halogenated hydrocarbon pesticides were assayed in the southwest monsoon winds and enter the Bay of Bengal at levels of a half ton per month, an amount comparable to those introduced by other wind and river systems to the marine environment.