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The loess-paleosol proxy records from mid-latitude Asia have been instrumental in the reconstruction of regional paleoclimate evolution and its relationship with global climatic changes. The present study explores the discrete occurrence of a loess and paleosol sequence (LPS) in the Southern Zanskar Range (SZR), NW Himalaya. Stratigraphic variations in sediment texture, supplemented with geochemical, organic and magnetic proxies, indicate two broad phases of loess accretion (L-1) and paleosol formation (PS-1). The older phase of loess accretion (L-1) is dated between 2.5 ± 0.3 ka and >2.0 ka, whereas the L-2, which fully transformed into the modern soil (MS) probably deposited during the Little Ice Age (LIA) phase. The textural attributes (high sand content) of loess indicate source proximal deposition, whereas the geochemical and magnetic proxies point towards the pre-depositional weathering (in the source area). The PS-1 dated to 2189 ± 296 cal yr BP indicates improved moisture conditions, whereas the MS is assigned to post LIA warm phase. These findings provide an important step towards better understanding the sensitivity of loess accretion and paleosol formation in the SZR linked to late Holocene climate variability. [ABSTRACT FROM AUTHOR]

Surface sediments were collected from Wular Lake, located in Bandipora district of Kashmir Valley, NW Himalaya to investigate the environmental risk assessment using trace element concentrations. The surface sediments of the lake reveal higher concentration of Cl, Cr, Ni, Cu, Co, Pb, Zn and Th. In order to estimate the impact of metal pollution on the sediments, the trace element data was quantified for enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI) and contamination factor (CF). The average values for Igeo reveal moderate to strong contamination of Ni, Cu, while Cr and Co exhibit moderate to strong contamination in the central part of the lake. EF reveals minor enrichment of Cu, Ni, Cr, Co and Zn in the lake surface sediments. PLI indicate moderate pollution from all the sampling sites. Spatial distribution of the metal in the lake reveals their transport through the sewage from the urbanized areas and the Jhelum river. Since metal pollution in the lake is still at nascent stage, it demands attention of the local authorities and the Lake Conservation Department to take remedial measures for the protection of this freshwater body from further contamination. [ABSTRACT FROM AUTHOR]

Integrating multiproxy results (geochemistry, mineral magnetism, grain size, and C/N ratio variability supported by 14C AMS dating), obtained from a 1.4-m sediment core retrieved from high-altitude Anchar Lake, Kashmir Valley, NW Himalaya, we present a 6000-years record of paleoenvironmental and paleolimnological shifts. Phase 1 (6000–4700 cal. yr BP) revealed a wetter climate with a significant terrestrial input corresponding to the gradual strengthening of the westerlies. Phase 2 (4700–3900 cal. yr BP) reflects an overall improved westerly precipitation and autochthonous sources of organic matter (OM). Magnetic parameters also indicate higher lake levels and reducing conditions during this phase. Phase 2 was followed by a gradual diminishing pattern of the westerlies as also represented by phase 3 (3900–2500 cal. yr BP) and phase 4 (2500–1600 cal. yr BP) indicating moderate precipitation conditions, catchment stability, and temperate and/or cold-dry climatic conditions. Phase 5 (1600–500 cal. yr BP) revealed the prevalence of moderately cold/dry and further subdued westerly precipitation. Phase 6 (500 cal. yr BP to present) is represented by reduced westerly precipitation, shrinking lake margins, and significant terrestrial/anthropogenic controls over the lake basin. Mineral magnetic parameters indicate reducing lake bottom water conditions and eutrophication during this phase due to anthropogenic activities. These paleoenvironmental shifts reveal near synchronous changes (within dating uncertainties) with other regional paleoclimate records close to the present Anchar Lake location and reflect the gradual late-Holocene diminishment of the amount of winter/early summer moisture provided by the mid-latitude westerlies. [ABSTRACT FROM AUTHOR]

Paleoclimate investigations and reconstruction using the lake sediment cores of Kashmir Valley have been rarely attempted. The basin is influenced by Indian Summer Monsoon, Westerlies and the local katabatic winds. In the present study, an 80 cm undisturbed sediment core was retrieved from the Manasbal Lake situated in North western Himalaya. Sediments were dated using 14C method, and the age-depth model indicated a depositional history extending from ∼3345 yrs BP to the present. Grain size, major and trace elements, TOC, OM contents C/N ratio and diatom assemblages were applied to reconstruct the paleoenvironmental changes around the area. The A-CN-K diagram displays that the weathering intensity of the Manasbal lake sediments are moderate to highly weathered and the sediments have been derived from nearby and mixed source origin. Several wet and cold phases were identified during ∼3300 yrs BP to ∼2500 yrs BP and ∼1800 yrs BP to ∼1300 yrs BP due to intense precipitation reflect high lake level. These wet phases are marked by higher sand and silt content, C/N ratio and high allochthonous input with less abundance of diatom species, clay, OM, TOC contents and high CIA values. Consequently, low lake level and dry and cold period from ∼3345 yrs BP to ∼3300 yrs BP and ∼2500 yrs BP to ∼1800 yrs BP is observed. These inferences are corroborated with the trace elemental ratios CIA and CWI data. Our data indicate that the Westerlies and localised katabtic winds rather than the Indian summer monsoons played a major role in controlling the past climate around the Manasbal lake, Kashmir Valley. [ABSTRACT FROM AUTHOR]

• Precipitation δ18Os at the NW Himalaya show different values during monsoon and non-monsoon season. • δ18Os during the WD events show strong correlation with the regional meteorological parameters. • This property establishes relation between precipitation δ18O and the meteorological parameters. The Kashmir Valley represents a critical region for understanding isotopic changes in the atmospheric moisture sources since it is located at the intercept between the influences of mid-latitude westerlies and the southwest monsoon circulation. This study presents the variation in isotopic composition (δ18O and δ2H) of daily precipitation samples collected from the Kashmir Valley, North-Western Himalaya, to quantify the effect of meteorological parameters, separately for the Southwest monsoon (SWM) season and the periods of Western Disturbances (WDs). The results suggest that precipitation isotopic composition is strongly modulated by temperature and relative humidity during the periods of WDs. Still, this dependency is weak in the case of the SWM season. Moisture transport pathways calculated from HYSPLIT back trajectory analysis shows a wide spatial variability during the monsoon season. On the other hand, the origin of moisture during the WD season was mostly restricted from the Mediterranean region, providing an explanation of a strong dependency between the precipitation isotopes and the meteorological parameters during the WD period. Such kind of relation may provide additional diagnostic for the WD events and may help in paleo-monsoon investigations. [ABSTRACT FROM AUTHOR]