S. Nawaz Ali

Drainage morphometry of Himalayan Glacio-fluvial basin, India: hydrologic and neotectonic implications

Morphometric analysis, being widely used to assess the drainage characteristics of the river basins, has been found to be a useful tool to delineate the glacial till covered overburden material as well as to identify areas prone to flash floods in present studies. A number of parameters including the stream frequency, drainage density and drainage texture suggest that the unconsolidated, unstratified and highly permeable glacially deposited overburden till material facilitates the infiltration of snowmelt and rainwater in the Pindari glacio-fluvial basin, Eastern Kumaun Himalaya, India. Likewise, other till overburden covered glacial and proglacial areas of Higher Himalayan regions have been contributing to the groundwater budget. The shape parameters further suggest that the sub-basins with higher form factor are more prone to flash floods. Besides this, the anomalies in the morphometric parameters have been found to be a useful tool to delineate zones of active tectonics in such areas.

Chronology of late quaternary glaciations in Indian Himalaya: A critical review

The timing of glaciation is an important parameter that helps in the understanding of past climate change and provides valuable information for developing the predictive futuristic models. There are evidences to suggest that during the late Quaternary, Himalayan glaciers fluctuated considerably thus implying their sensitivity to changes in past climatic conditions. Although the Himalayan region is fed by two major weather systems viz. the southwest summer monsoon and the mid-latitude westerlies, however, the existing chronology (mostly exposure ages) indicates that irrespective of the geographical position, glaciers seem to grow during increased insolation and enhanced southwest summer monsoon including the mid-latitude westerly dominated north-western Himalayan glaciers (Ladakh and Karakoram). Considering the limited geographical coverage and the dating uncertainty, the above inferences should be treated as tentative.

Modern Pollen Rain from Udhampur (Jammu and Kashmir), India: Insights into Pollen Production, Dispersal, Transport and Preservation

ABSTRACT The present communication deals with pollen analyses of moss polsters in order to understand the pollen rain from Udhampur District of Jammu and Kashmir, India. The study revealed that the pollen of Pinus sp. (average 46% pollen) dominates the pollen rain, which could be attributed to its high pollen productivity and excellent pollen dispersal efficiency, followed by Cedrus sp., and Podocarpus sp. However, other conifers such as Abies sp., Picea sp., Juniperus sp. and Tsuga sp., as well as the broad-leaved taxa such Alnus sp., Betula sp., Ulmus sp., Quercus sp., Carpinus sp., Corylus sp., Juglans sp., Ilex sp., Mallotus sp., Elaeocarpus sp. and Aesculus sp., were sporadically recorded which could be due to either their poor pollen dispersal efficiency or poor preservation in the substrate. Tubuliflorae, Poaceae, Amaranthaceae, Malvaceae and Cerealia are the other prominent taxa of the pollen rain, revealing their actual composition in the ground vegetation.

Impact of Anthropocene Vis-à-vis Holocene Climatic Changes on Central Indian Himalayan Glaciers

Systematic palaeoclimatic study of the glacio-lacustrine sediments using multiproxy data in Pindari glacier area, Central Himalaya has helped in better understanding of the climatic fluctuations since the last 7 Ka. The palynological data supported by the environmental magnetic parameters suggests that the climate of the Pindar valley was cold and dry during 7 ka BP followed by five different vegetational shifts. The studies further suggest that since the last 300 yr BP, the climate has been warm and moist. It has to be ascertained weather the present phase of warming as inferred from the current phase of deglaciation is anthropogenic or is the continuation of the warm period that was initiated prior to the anthropocene time around 300 years B.P.