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Due to the significant sedimentation and anthropogenic pressures, the Kashmir Himalaya lakes (Dal, Wular, Manasbal) located within and in the vicinity of urban settlements are experiencing massive degradation. The unique climate, geographic setting, and rock degradation owing to the tectonic uplift of the area, contribute to increased sedimentation in these lakes. The sewage and other anthropogenic pressures have also increased various minerals including nitrogen influx in these lakes. Total organic carbon levels in the Dal Lake are high and range from 2.72% to 25.12%, with nitrogen levels ranging from 0.92% to 9.81%. The total organic carbon of Wular and Manasbal Lakes ranges from 0.83% to 4.52%, and 3.11% to 13.74% with nitrogen ranging from 0.06% to 0.5% and 0.20% to 1.96%, respectively. The estimated sedimentation rates for the Wular, Manasbal, and Dal Lakes are 0.125 cm/yr, 0.44 cm/yr, and 0.93 cm/yr. Given these factors and the geographic setting of Kashmir Himalaya, it is believed that under the sustained threat of climate change and anthropogenic pressure, mitigation strategies to control sedimentation and pollution are unavoidable for the long‐term survival of these valuable ecosystems. This review examines contributing factors, explores potential consequences, and proposes mitigation measures, to save these important aquatic ecosystems from further deterioration. [ABSTRACT FROM AUTHOR]

Continuous multiproxy data were generated to understand the mid-late Holocene palaeoenvironmental history of the Kashmir Valley and the biogeochemistry of Wular Lake, India. For this purpose, geochemical and stable isotopic analyses were carried out on sediment samples retrieved from a 160 cm long trench excavated on the eastern bank of Wular Lake located in the Union Territory of Jammu and Kashmir, India. The chronology of the sediment strata developed using 14C dating by accelerator mass spectrometry covered the last ~5600 yr BP. Our results indicated the occurrence of an extended dry climate phase from 4600 to 3800 yr BP, which coincided with the widely recognised Meghalayan Stage, when major civilisations like the Harappa and the Akkadian were known to collapse. The lake biogeochemistry revealed dominance of the emergent macrophytes during this stage. Another dry phase was observed between 3100 and 2200 yr BP. This dry phase peaked at around 2900 yr BP, coinciding with Bond Event 2. Wular Lake faced nutrient limitation due to low runoff around 2500 yr BP caused by the persistent dry and cold climate. Geochemical signatures revealed that anthropogenic activities during the last two millennia might have significantly influenced erosion in the catchment area. [ABSTRACT FROM AUTHOR]

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]