Assessment of future water provisioning and sediment load under climate and LULC change scenarios in a peninsular river basin,India

Assessment of the impact of changes in climate and land use and land cover (LULC) on ecosystem services (ES) is important for planning regional-scale strategies for sustainability and restoration of ES. The Upper Narmada River Basin (UNRB) in peninsular India has undergone rapid LULC change due to recent agricultural expansion. The impact of future climate and LULC change on ES in the UNRB is quantified and mapped using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST 3.3.0) tool. Our results show that water yield is projected to increase under climate change (about 43% for representative concentration pathway 4.5 for 2031–2040), whereas it is projected to decrease under the LULC change scenario. Sediment export is projected to increase (by 54.53%) under LULC change for 2031–2040. Under the combined effect of climate and LULC change, both water yield and sediment export are expected to increase. Climate change has a greater impact on projected water yield than LULC change, whereas LULC has greater impact on sediment export. Spatial analysis suggests a similar trend of variation in relative difference (RD) of ES in adjacent sub-basins. The quantified changes in ES provisioning will benefit future land management, particularly for operation of the Rani Avanti Bai Sagar Reservoir downstream of the UNRB.     

Plant studies in the first Himalayan Biosphere Reserve: a review

Nanda Devi Biosphere Reserve(NDBR) was declared as the first Himalayan Biosphere Reserve owing to its unique biological and cultural wealth. Its core zones, Nanda Devi National Park and Valley of Flowers National Park, are a UNESCO World Natural Heritage Site. In spite of lying at a high altitude, interplay of factors such as unique geographical location, climate, topography and wide altitudinal variations have endowed NDBR with a rich and diverse flora. Proportionately high percentage of endemic and near endemic plants makes NDBR a very important protected area from conservation point of view. However, its floristic wealth is facing unprecedented threats in the form of climate change and growing anthropogenic pressure. Hence, a need was felt to assess the directionality, quality and sufficiency of past and ongoing research for the conservation of floral and ethnobotanical wealth of NDBR in the absence of any such previous attempt. Based on an extensive review of more than 150 plant studies on NDBR, this communication provides a detailed account of the current state of knowledge and information gaps on flora, vegetation ecology, rare, endangered, threatened(RET) and endemic plants and ethnobotany. Priority research areas and management measures are discussed for the conservation of its unique floral wealth. Incomplete floral inventorization, lack of biodiversity monitoring, meagre studies on lower plant groups, population status of medicinal plants, habitat assessment of threatened taxa and geo-spatial analysis of alpine vegetation were identified as areas of immediate concern.     

Field evidences showing rapid frontal degeneration of the Kangriz glacier,western Himalayas,Jammu & Kashmir

Life cycle of glaciers in the Himalayan region has notably changed due to the climatic variability since last few decades. Glaciers across the world and specially the Himalayan glaciers have shown large scale degeneration in the last few decades. Himalayan glaciers serve as an important fresh water resource for the downstream communities, who are dependent on this water for domestic and other purposes. Therefore, glacier shrinkage and the associated hydrological changes pose a significant problem for regional-scale water budgets and resource management. These issues necessitate the regular and rigorous monitoring of the wastage pattern of the Himalayan glaciers in field and using satellite remote sensing data. In this work, we report rapid and enhanced degeneration of the frontal part of the Kangriz glacier, Jammu and Kashmir(J K), in terms of surface melting, debris cover, snout characteristics and meltwater discharge. Ablation data acquired during 2016-2017 shows the average lowering of the frontal part of the glacier to be ~148 ± 34 cm, one-third of which was found to have occurred within a 13 day time period in September, 2017. Also, the quantum of ice melt was found to be inversely influenced(r =-0.84) by the debris thickness. 15 day meltwater discharge measurement revealed its strong relationship with snout disintegration pattern, evidenced twice during the said time period. Volume of water discharged from the glacier was estimated to be 7.91×10~6 m~3 for the measurement duration. Also, mean daily discharge estimated for the 15 days interval showed good positive correction(r = 0.78) with temperature indicating the direct dependency of the former on land surface temperature conditions of the region. Besides the lowering and discharge observations, the frequent ice-block break-offs at the glacier snout further enhance its overall drastic degeneration. The study suggests that, being the largest glacier in the Suru basin, the Kangriz glacier needs to be continuously monitored in order to understand its glacio-hydrological conditions.     

Evolution of Quaternary alluvial fans and terraces in the intramontane Pinjaur Dun, Sub-Himalaya, NW India: interaction between tectonics and climate change

Quaternary alluvial fans in the tectonically active Pinjaur Dun, an intramontane valley in the Sub‐Himalaya, were deposited in front of the Nalagarh Thrust and were influenced both by tectonics and glacial climate fluctuations. The surface morphology indicates that an earlier set of first‐order fans (Qf1) became entrenched and onlapped by a series of second‐order fans (Qf2). The younger fan segments were then cut by a pair of terraces (T1 and T2). Quartz optically stimulated luminescence dating establishes that the Qf1 aggradational phase was initiated before 96·5 ± 25·3 ka and terminated after 83·7 ± 16·3 ka. This was followed by a period of incision, before Qf2 fan deposition started at 72·4 ± 13·4 ka and continued until 24·5 ± 4·9 ka. Sediment was deposited on the T1 (upper) and T2 (lower) terraces at 16·3 ± 2·1 and 4·5 ka, respectively, recording a return to overall degradation punctuated by minor deposition on terraces. The period of incision separating the younger and older fan deposits coincided with enhanced SW monsoon precipitation. The subsequent development of the Qf2 fans and their progradation until 20 ka suggest erosional unloading of the thrust hangingwall during a tectonically quiescent phase. Toe cutting, deposition of axial river and lacustrine facies, and retreat of Qf2 around 45 ka, indicate fanward shift of the axial river due to tilting of the valley towards the NE in response to reactivation of the Nalagarh Thrust. The cessation of Qf2 deposition around 20 ka and the onset of through‐fan entrenchment suggest reduced sediment supply but relatively high stream power during the last glacial maxima (LGM). The prolonged stream incision since the cessation of Qf2 deposition, with only minor depositional phases at 16·3 ± 2·1 and 4·5 ka, resulted from high water discharge and low sediment input during intensification of the SW monsoon and vegetation changes in the hinterland.     

Ground-Based In Situ Measurements of Near-Surface Aerosol Mass Concentration over Anantapur: Heterogeneity in Source Impacts

Surface measurements of aerosol physical properties were made at Anantapur(14.62°N,77.65 °E,331 m a.s.l),a semiarid rural site in India,during August 2008-July 2009.Measurements included the segregated sizes of aerosolsas as well as total mass concentration and size distributions of aerosols measured at low relative humidity(RH<75%) using a Quartz Crystal Microbalance(QCM) in the 25-0.05 μm aerodynamic diameter range.The hourly average total surface aerosol mass concentration in a day varied from 15 to 70 μg m-3,with a mean value of 34.02±9.05μgm-3 for the entire study period.A clear diurnal pattern appeared in coarse,accumulation and nucleation-mode particle concentrations,with two local maxima occurring in early morning and late evening hours.The concentration of coarse-mode particles was high during the summer season,with a maximum concentration of 11.81±0.98μgm-3 in the month of April,whereas accumulationmode concentration was observed to be high in the winter period contributed >68% to the total aerosol mass concentration.Accumulation aerosol mass fraction,A f(=Ma/Mt) was highest during winter(mean value of Af～0.80) and lowest(Af～0.64) during the monsoon season.The regression analysis shows that both R eff and R m are dependent on coarse-mode aerosols.The relationship between the simultaneous measurements of daily mean aerosol optical depth at 500 nm(AOD500) and PM 2.5 mass concentration([PM2.5]) shows that surface-level aerosol mass concentration increases with the increase in columnar aerosol optical depth over the observation period.     

A Spectro-radiometric Analysis of Ocean Colour Sensors and Proposal for a Miniature Hyper Spectral Imager for Future

Ocean colour sensors traditionally are of fixed spectral channel systems with specified bandwidth of about 20 nm in the visible region and about 40 nm in Near Infrared region. In these systems, it is known that a radiometric error of 1% in the measurement of top of the atmosphere signal may lead to an error of 10% in the retrieved ocean upwelling radiance. In this paper we investigated the range of wavelengths participating in signal collection (effective spectral pass band, ESPB) using relative spectral response data of various sensors flown earlier. ESPB values were computed for each spectral channel for various percentages of signal and the results showed that they are quite high compared to bandwidths specified. These values were found to vary with sensor and channel. ESPB shall be small for accurate computation of spectral radiance. As the knowledge of spectral profile of the signal in the range of ESPB helps in better estimation of spectral radiance at the intended wavelengths, a miniature high performance linear variable filter based hyperspectral sensor is proposed as an alternative. We present here the design concept and report the estimated performance of such sensor that can be realized even with commercial off the shelf components for operational implementation.