Central Himalayan Region Research Articles

Spatial-temporal trend analysis of seasonal and annual rainfall (1966–2015) using innovative trend analysis method with significance test

This study investigates the spatial and temporal patterns of trends on seasonal (pre-monsoon, monsoon, post-monsoon, and winter) and annual rainfall time series data (1966–2015) at 13 stations located in the central Himalayan region of the Uttarakhand State of India. The temporal trend was analyzed using recently proposed innovative trend analysis (ITA) method with significance test. The results of the ITA method were compared with the Mann-Kendall (MK) test at 5% significance level. The spatial variation of the trends in seasonal and annual rainfall series was interpolated using the Thiessen polygon (TP) method in ArcGIS 10.2 environment. The results of comparison revealed that the trend detected by MK test (significantly positive in 3-time series and significantly negative in 6-time series) can be effectively identified using ITA (significantly positive in 19-time series and significantly negative in 32-time series). The ITA method could detect some trends that cannot be observed by the MK test. According to the spatial distribution of MK test, significantly increasing (decreasing) trends were observed in 1 (0), 1 (2), 0 (1), 1 (1), and 1 (1) polygons in pre-monsoon, monsoon, post-monsoon, winter, and annual rainfall data, while the ITA method detected significant trends in 3 (7), 6 (5), 1 (9), 4 (5), and 5 (6) polygons in the study region. The developed maps of spatial variability of rainfall trends may help the stakeholders and/or water resource managers to figure out the risk and vulnerability related to climate change in the study region.

An Analysis of Land Surface Temperature Trends in the Central Himalayan Region Based on MODIS Products

The scientific community has widely reported the impacts of climate change on the Central Himalaya. To qualify and quantify these effects, long-term land surface temperature observations in both the daytime and nighttime, acquired by the Moderate Resolution Imaging Spectroradiometer from 2000 to 2017, were used in this study to investigate the spatiotemporal variations and their changing mechanism. Two periodic parameters, the mean annual surface temperature (MAST) and the annual maximum temperature (MAXT), were derived based on an annual temperature cycle model to reduce the influences from the cloud cover and were used to analyze their trend during the period. The general thermal environment represented by the average MAST indicated a significant spatial distribution pattern along with the elevation gradient. Behind the clear differences in the daytime and nighttime temperatures at different physiographical regions, the trend test conducted with the Mann-Kendall (MK) method showed that most of the areas with significant changes showed an increasing trend, and the nighttime temperatures exhibited a more significant increasing trend than the daytime temperatures, for both the MAST and MAXT, according to the changing areas. The nighttime changing areas were more widely distributed (more than 28%) than the daytime changing areas (around 10%). The average change rates of the MAST and MAXT in the daytime are 0.102 °C/yr and 0.190 °C/yr, and they are generally faster than those in the nighttime (0.048 °C/yr and 0.091 °C/yr, respectively). The driving force analysis suggested that urban expansion, shifts in the courses of lowland rivers, and the retreat of both the snow and glacier cover presented strong effects on the local thermal environment, in addition to the climatic warming effect. Moreover, the strong topographic gradient greatly influenced the change rate and evidenced a significant elevation-dependent warming effect, especially for the nighttime LST. Generally, this study suggested that the nighttime temperature was more sensitive to climate change than the daytime temperature, and this general warming trend clearly observed in the central Himalayan region could have important influences on local geophysical, hydrological, and ecological processes.

Changing aerosol loadings over Central Himalayan region (2007–2016) – A satellite perspective

The paper presents the variation of aerosol columnar variation and vertical profiles over the study area encompassing a portion of Central Himalayan region and the surrounding planar areas. The analysis is carried out using decadal (2007–2016) Level-2 CALIOP (onboard CALIPSO), Level-3 MODIS (onboard Aqua/Terra) and MISR (onboard Terra) datasets. Four seasons have been considered, namely, DJF (December-January-February), MAM (March-April-may), JJA (June-July-August) and SON (September-October-November). The CALIOP data has been screened using quality flags, i.e., CAD score, aerosol layer fraction and extinction quality checks. There are also signatures of elevated aerosol layers, especially during winter (DJF) and post-monsoon (SON) seasons. Latitudinal and longitudinal variations of the vertical structure have also been presented. The HYSPLIT back-trajectory analysis has been carried out in order to explore the changes in the sources of the aerosols during different seasons. It is seen that as we go higher up in the altitudes, the long range transport becomes more dominant. Compared to the other seasons, the air masses are more localized in JJA season. The changing aerosol amounts at different heights of the atmosphere have also been discussed in terms of decadal trends for the four seasons. These trends have been supplemented by the AOD trends from the passive satellite sensors. We find that aerosol amounts have increased in the last decade during DJF and SON seasons, when the atmospheric conditions are more stable. On the contrary, aerosol amounts have significantly decreased in JJA season throughout the vertical column. The effect of changing amounts of aerosols may have impacts on the snow cover variability as well. In this connection, the seasonal trends in snow cover have also been explored during the considered decadal period. Especially during the DJF and SON seasons, decreasing trends in snow cover are observed when the aerosol amounts have been found to be increased.

Physicochemical and microbiological assessment of spring water in central Himalayan region

In the present study, water quality of 16 springs, located along National Highway-58 from Rishikesh to Badrinath in India, was assessed by determining various physicochemical and microbiological parameters in three different seasons, i.e., pre-monsoon, monsoon, and post-monsoon. For majority of the springs, the pH was slightly alkaline with temperature ranging between 10 and 27°C. All other parameters such as total hardness (TH), total alkalinity (TA), chloride, phosphate, nitrate, total dissolved solids (TDS), electrical conductivity (EC), dissolved oxygen (DO), and biochemical oxygen demand (BOD) were found to lie within the acceptable limit prescribed by various standard national and international agencies. The principal component analysis reveals that water quality of springs mainly depends on mineral contents of water, as there is a loading of TH, TA, EC, TDS, and other mineral components during one or other season of a year. The positive correlation coefficients determined among mineral components of spring water further substantiate this fact. No loading of DO, BOD, nitrate, and phosphate indicates an absence of anthropogenic pollution in the studied area. No trace metals were detected in any of the springs. Most probable number (MPN) index for coliforms was found to be above the acceptable limit for all the springs in one or more seasons of a year, except the one in Pandukeshwar. Plate-based assay revealed the presence of pathogens like Salmonella, Shigella, Vibrio, and Pseudomonas in some spring water. The findings of the present work reveal that due to high MPN index and presence of other pathogenic bacteria, water from most of the springs cannot be considered completely safe for direct human consumption in its raw form.

Energy audit of livestock production system in a mid-altitude Himalayan agro-ecosystem

The present study analyses energy flows through livestock production system and works out energy audit in selected mid-altitude villages in the Pithoragarh district of the Kumaun Division of Uttarakhand lying in the Central Himalayan region. The livestock population (converted into livestock units) consumed 144638094.9 kJ/day or 52792904649 kJ in a year and, in turn, produced 8490715137.07 kJ in a year through dung, 2056277724 kJ though milk, 60704289.30 kJ through calf crop and 6416.35 kJ by means of draught power supply to various agricultural operations. The gross energy produced by livestock was 10607703567 kJ/year. Proportion of the output energy from dung (80%) was much more than from milk (19%). Contribution of calf crop and draught animal power (DAP) was minimal compared to the overall energy. The gross energetic efficiency of livestock production was 20.09%. Energy for maintenance and growth available for livestock was 25.15%. The study reveals that a substantial proportion of energy in a mountain agro-ecosystem flows through livestock.

An overview of airborne measurement in Nepal – Part 1: Vertical profile of aerosol size, number, spectral absorption, and meteorology

Abstract. The paper provides an overview of an airborne measurement campaign with a microlight aircraft over the Pokhara Valley region, Nepal, a metropolitan region in the central Himalayan foothills. This is the first aerial measurement in the central Himalayan foothill region, one of the polluted but relatively poorly sampled regions of the world. Conducted in two phases (in May 2016 and December 2016–January 2017), the goal of the overall campaign was to quantify the vertical distribution of aerosols over a polluted mountain valley in the Himalayan foothills, as well as to investigate the extent of regional transport of emissions into the Himalayas. This paper summarizes results from the first phase where test flights were conducted in May 2016 (pre-monsoon), with the objective of demonstrating the potential of airborne measurements in the region using a portable instrument package (size with housing case: 0.45 m × 0.25 m × 0.25 m, 15 kg) onboard an ultralight aircraft (IKARUS-C42). A total of five sampling test flights were conducted (each lasting for 1–1.5 h) in the Pokhara Valley to characterize vertical profiles of aerosol properties such as aerosol number and size distribution (0.3–2 µm), total particle concentration (>14 nm), aerosol absorption (370–950 nm), black carbon (BC), and meteorological variables. Although some interesting observations were made during the test flight, the study is limited to a few days (and only a few hours of flight in total) and thus the analysis presented may not represent the entire pollution–meteorology interaction found in the Pokhara Valley. The vertical profiles of aerosol species showed decreasing concentrations with altitude (815 to 4500 m a.s.l.); a steep concentration gradient below 2000 m a.s.l. in the morning; and mixed profiles (up to ca. 4000 m a.s.l.) in the afternoon. The near-surface (<1000 m a.s.l.) BC concentrations observed in the Pokhara Valley were much lower than pre-monsoon BC concentrations in the Kathmandu Valley, and similar in range to Indo-Gangetic Plain (IGP) sites such as Kanpur in India. The sampling test flight also detected an elevated polluted aerosol layer (around 3000 m a.s.l.) over the Pokhara Valley, which could be associated with the regional transport. The total aerosol and black carbon concentration in the polluted layer was comparable with the near-surface values. The elevated polluted layer was also characterized by a high aerosol extinction coefficient (at 550 nm) and was identified as smoke and a polluted dust layer. The observed shift in the westerlies (at 20–30∘ N) entering Nepal during the test flight period could be an important factor for the presence of elevated polluted layers in the Pokhara Valley.

Spatial and temporal distribution of total mercury in atmospheric wet precipitation at four sites from the Nepal-Himalayas

The studies on global pollutant mercury (Hg), which is of public concern due to its high toxicity and capacity to long-range transport via atmospheric circulation, is poorly characterized in wet deposition over the Nepal-Himalayas region. Therefore, in order to understand the concentration levels, spatial distribution and seasonal variation of total Hg, 333 precipitation samples were collected from south to north: Kathmandu (1314 m a.s.l.), Dhunche (2065 m a.s.l.), Dimsa (3078 m a.s.l.) and Gosainkunda (4417 m a.s.l.) characterized as urban, rural, remote forest and remote alpine sites, respectively, for over one-year period. The highest Hg concentration was found in Kathmandu comparable to the urban sites worldwide, and significantly lower concentrations at other three sites demonstrated similar levels as in rural and remote alpine sites worldwide. Higher wet deposition fluxes of 34.91 and 15.89 μg m−2 year−1 were found in Kathmandu and Dhunche respectively, due to higher precipitation amount. Clear and distinct seasonal differences were observed with higher concentrations in non-monsoon and lower values in monsoon periods due to less scavenging and high pollutant concentration loadings during the dry period. The positive correlation of Hg flux and precipitation amount with Hg concentration suggested that both precipitation amount and Hg concentration plays a vital role in Hg deposition in the central Himalayan region. Enrichment factor (EFHg) indicated that the anthropogenic emission sources play a significant role for Hg enrichment and a high ratio of EFmonsoon to EFnon-monsoon (>2.18) suggested that the anthropogenic atmospheric mercury could likely be long-range transported from south Asian regions to the Himalayas during the monsoon season. In addition, our results showed that the major ionic compositions (e.g., SO42−, NO3−, NH4+, K+, Ca2+) could influence Hg concentration in wet precipitation. The anthropogenic sources of Hg such as biomass and fossil fuel combustion, crustal aerosols may contribute to the Hg concentration in wet precipitation over the central Himalayas.

Study of Physico-chemical and Biological Characteristics of the Water of River Ganga at Patna, India

River Ganga arises on the southern slopes of the Indian central Himalayan region beginning the Gangotri glacier. The river covers catchment area of 8, 61,404 km2 and its total length in the state Bihar stretch is 475 km. This study was carried out at Patna in the river Ganga at two sampling sites, viz., Digha Ghat (upstream) and Gai Ghat (downstream). The objective of the study was to observe the eminence of water of Ganga at Patna. The results that indicate that the river reaches near the city of Patna (upstream at Digha Ghat) are less polluted with pH 7.75, DO 7.42 mg/l, BOD 2.48 mg/l and COD 15.12 mg/l, while when the river leaves city after travelling 18 km (downstream at Gai Ghat), concentration of all pollutants increases significantly (pH 6.28, DO 6.22 mg/l, BOD 2 mg/l and COD 23 mg/l). The concentration of coliform bacteria (total coliform ranges from 5000 to 6000 MPN/100ml and faecal coliform ranges from 2200 MPN/100ml and 3000 MPN/100ml at both the sites) was recorded at higher level than the upper limit of the permissible level. This increment may be due to domestic and sewage discharge from the city. The municipality of Patna has sewage treatment plant capacity of about 109 MLD but whereas the city generates approximately 250 MLD sewage/township discharge. For the maintenance of pristine quality of water of the river Ganga, the sewage need be treated before discharge

Selinum vaginatum C. B. Clarke: Terpenoid Composition and Antibacterial Activity of Whole Aerial Parts and Root Essential Oil

The steam volatile constituents from the aerial parts and roots of Selinum vaginatum C. B. Clarke (Apiaceae) growing wild in the central Himalayan region of Uttarakhand, India were isolated by steam distillation and analyzed by capillary gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of thirty-one and forty-six constituents, representing 97.7 % and 96.7 % of the total oil composition were identified from the aerial parts and roots of S. vaginatum, respectively. The aerial parts oil consisted mainly of monoterpene hydrocarbons (48.7 %), with 2E,6E-farnesol (36.0 %), γ-terpinene (24.3 %) and β-pinene (16.3 %) as a major constituents while the roots oil mainly contains oxygenated sesquiterpenes (72.8 %), with maximum content of 2E,6Z-farnesol (60.0 %) and elemol (5.0 %). The oil samples showed significant antibacterial activity against Gram-positive Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis and Gram-negative Klebsiella pneumoniae. Minimum inhibitory concentration value (31.25 μL/mL) of the essential oil from the aerial parts was observed against Bacillus subtilis, Xanthomonas phaseoli, Klebsiella pneumoniae and Pasteurella multocida whereas from roots it was observed against Bacillus subtilis, Enterococcus faecalis, Erwinia chrysanthemi, Klebsiella pneumoniae and Salmonella enterica enterica. Both the oil samples showed bactericidal effect against B. subtilis, S. enterica enterica and E. faecalis at 62.5, 125 and 250 μl/mL, respectively.

Variations in surface ozone and carbon monoxide in the Kathmandu Valley and surrounding broader regions during SusKat-ABC field campaign: role of local and regional sources

Abstract. Air pollution resulting from rapid urbanization and associated human activities in the Kathmandu Valley of Nepal has been leading to serious public health concerns over the past 2 decades. These concerns led to a multinational field campaign SusKat-ABC (Sustainable atmosphere for the Kathmandu Valley – Atmospheric Brown Clouds) that measured different trace gases, aerosols and meteorological parameters in the Kathmandu Valley and surrounding regions during December 2012 to June 2013 to understand local- to regional-scale processes influencing air quality of the Kathmandu Valley. This study provides information about the regional distribution of ozone and some precursor gases using simultaneous in situ measurements from a SusKat-ABC supersite at Bode, Nepal, and two Indian sites: a high-altitude site, Nainital, located in the central Himalayan region and a low-altitude site, Pantnagar, located in the Indo-Gangetic Plain (IGP). The diurnal variations at Bode showed a daytime buildup in O3 while CO shows morning and evening peaks. Similar variations (with lower levels) were also observed at Pantnagar but not at Nainital. Several events of hourly ozone levels exceeding 80 ppbv were also observed at Bode. The CO levels showed a decrease from their peak level of about 2000 ppbv in January to about 680 ppbv in June at Bode. The hourly mean ozone and CO levels showed a strong negative correlation during winter (r2 = 0.82 in January and r2 = 0.71 in February), but this negative correlation gradually becomes weaker, with the lowest value in May (r2 = 0.12). The background O3 and CO mixing ratios at Bode were estimated to be about 14 and 325 ppbv, respectively. The rate of change of ozone at Bode showed a more rapid increase ( ∼ 17 ppbv h−1) during morning than the decrease in the evening (5–6 ppbv h−1), suggesting the prevalence of a semi-urban environ. The lower CO levels during spring suggest that regional transport also contributes appreciably to springtime ozone enhancement in the Kathmandu Valley on top of the local in situ ozone production. We show that regional pollution resulting from agricultural crop residue burning in northwestern IGP led to simultaneous increases in O3 and CO levels at Bode and Nainital during the first week of May 2013. A biomass-burning-induced increase in ozone and related gases was also confirmed by a global model and balloon-borne observations over Nainital. A comparison of surface ozone variations and composition of light non-methane hydrocarbons among different sites indicated the differences in emission sources of the Kathmandu Valley and the IGP. These results highlight that it is important to consider regional sources in air quality management of the Kathmandu Valley.

What drives forest degradation in the central Himalayas? Understanding the feedback dynamics between participatory forest management institutions and the species composition of forests

Human populations and their socio-economic conditions, such as road networks and poverty, are thought to be the main drivers of deforestation. However, a high deforestation rate can also alter the species composition of forests, providing further feedback to the socio-economic drivers of deforestation as well as weakening the community forest management institutions. In this paper, we model the feedback linkages associated with the degradation of forests and the weakening of the local institutions to understand how they impact the long-term sustainability of these linked socio-economic-ecological systems. In particular, we explore the impact of excessive harvesting of forests for fuelwood and fodder on a shift in the species composition from oak to pine trees in the central Himalayan region of India. This shift provides adverse feedback to the communities' livelihoods and erodes the quality of their participatory management institutions. A change in the species composition also increases forest fire risks, which further exacerbates the ecological as well as socio-economic feedback effects. We develop and apply a dynamic optimization model of community forest management where, through optimally controlling harvesting efforts over time, a weighted sum of community and environmental objectives is maximized. Findings indicate that factors such as population size, the extent of dependence of the community on fuelwood, the strength of community institutions, and the degree of feedback effects, affect the long-term sustainability of forests. When faced with forest fire risks, there is a discounting effect present which increases deforestation and institutional entropy.

Conservation and Digital Access of Available Rare Collections of Central Himalaya Region: A Study of Kumaun University

The main objective of the study is to conserve and preserve manuscripts/rare books available at DSB Campus, Kumaun University, Nainital, Uttarakhand, India. Eventually, digitized them and upload in digital repository software at G.B. Pant Library. A survey method is applied and twenty four (24) questionnaires are distributed to the twenty four (24) departments of DSB Campus, Kumaun University. In the survey, researcher got the total 53 rare books and 24 manuscripts from Zoology, Physics, Forestry, Sanskrit, and Hindi Departments. The manuscripts/rare books are not available in remaining nineteen (19) departments of this campus. Preventive and curative work is being done only in twenty four (24) manuscripts of Sanskrit Department, due to the scarcity of funds. After that the images was captured through camera then deciphering the manuscripts through subject expert and making digital repository of these rare documents in Dspace software. The result revealed that Zoology Department contains 44 (23008 folios) rare books of general zoology, entomology, fish and fisheries, genetics, invertebrates and amphibiology. Physics Department contains 1 (470 folios) rare books of spectroscopy. Forestry Department contains 3 (1208 folios) rare books of silviculture. Hindi Department contains 3 (500 folios) rare books aalochanaye and kavitaye and Sanskrit Department contains 24 (297 folios) manuscripts. The conservation process enrich the rare documents and digitization makes them global accessible. The purpose of this study is same and we have tried to make these said documents accessible within the library premises and save the rich heritage culture of Central Himalayan Region of Uttarakhand, India.

Probabilistic seismic hazard for Himalayan region using kernel estimation method (zone-free method)

In view of active seismic status of the Himalayan belt and continued developmental activities in mountainous states, it is imperative to update knowledge of seismic hazard incorporating latest knowledge on earthquake occurrence and attenuation process. The present research work delivers new-generation probabilistic seismic hazard information for northwest and central Himalayan region. We adopted a noble approach following a zone-free method, first time, for the Himalayan region to estimate the ground motion at bedrock level, the results of which are compared with the contemporary zoning method for the same area. Employing new-generation ground motion prediction equations, peak ground acceleration and spectral acceleration have been estimated in the region for return periods of 475, 975 and 2475 years (10, 5 and 2% exceedance in 50 years, respectively). The zone-free method predicted maximum ground motions in two areas Kashmir valley and eastern part of the Uttarakhand and the westernmost part of the Nepal. The ground motion ranges from 0.04 to 0.60 g for 2475-year return period.

Molecular profiling of foxtail millet (Setaria italica(L.) P. Beauv) from Central Himalayan Region for genetic variability and nutritional quality

AbstractAgriculture in the Central Himalayan Region depends on the availability of suitable germplasm as well as natural conditions. Due to extreme weather conditions, food and nutrition security is a major issue for communities inhabiting these remote and inaccessible areas. Millets are common crops grown in these areas. Foxtail millet (Setaria italica(L.) P. Beauv) is an important crop and forms a considerable part of the diet in this region. The aim of the present study was to explore, collect, conserve and evaluate the untapped genetic diversity of foxtail millet at the molecular level and discover variability in their nutritional traits. A total of 30 accessions having unique traits of agronomic importance were collected and molecular profiling was performed. A total of 63 alleles were generated with an average of 2.52 alleles per locus and average expected heterozygosity of 0.37 ± 0.231. Significant genetic variability was revealed through the genetic differentiation (Fst) and gene flow (Nm) values. Structure-based analysis divided whole germplasm into three sub-groups. Rich variability was found in nutritional traits such as dietary fibre in husked grains, carbohydrate, protein, lysine and thiamine content. The collected germplasm may be useful for developing nutritionally rich and agronomically beneficial varieties of foxtail millet and also designing strategies for utilization of unexploited genetic diversity for food and nutrition security in this and other similar agro-ecological regions.

Sustainable agroforestry systems and their structural components as livelihood options along elevation gradient in central Himalaya

Himalayan ecosystems are complex, with fragile environment, rugged terrain, unique topography and sensitive to regional and global changes. This region harbours a variety of agricultural practices out of which traditional agroforestry systems are of paramount importance with regard to sustainability and livelihood. In the central Himalayan region, four major traditional agroforestry systems were observed; agrisilviculture (AS), agrihorticulture (AH), agrihortisilviculture (AHS) and agrisilvihorticulture (ASH). System units in each system varied from 8 to 24 and they also differed along the elevation. Likewise, structural components varied in the systems as well as along the elevation. These systems have evolved over long periods of time as farmers have grown the trees and crop combinations for generations. These systems fulfill diverse needs for food, fodder, fruit and timber for the inhabitants of the mountains and provide a backbone to the hill economy and livelihood security for local people.

Evaluation of barnyard millet diversity in central Himalayan region for environmental stress tolerance – Corrigendum

Evaluation of barnyard millet diversity in central Himalayan region for environmental stress tolerance – Corrigendum

Seed maturation timing in Quercus leucotrichophora A. camus along an altitudinal gradient in Uttarakhand Himalaya

Quercus leucotrichophora A. Camus is a dominant forest forming species in Central Himalayan region between 1600 and 2100 m elevation. The species is under severe anthropogenic pressure and failing to regenerate in its natural environment. Climatic irregularities may further aggravate the problem as acorn ripening time may shift. Acorns of Q. leucotrichophora were collected from three sites located along the altitudinal limits of the species to determine the acorn maturation time. Across the sites the mean weight of acorns between the first and final collection ranged from 9.3±2.2 gm to 21.6±2.1. Inspite of variation in moisture content initial germination commenced at the same time across the sites. Maximum acorn germination was between 56.7±1.2 and 59.6±0.6. The mean acorn size was larger at the lower elevation site than higher elevation site across the collection dates. The change in acorn colour from green to dark brown, the removal of acorns cap with ease and acorn moisture content between 36.4±0.8 – 37.6±1.2 at the time of maximum germination appear to be reliable indication of maturity. Comparison with an earlier study indicates that acorns are now maturing earlier which can be severely affects its regeneration potential.

Bio-assessment of River Ujh using benthic macro-invertebrates as bioindicators, India

ABSTRACTRapid bio-assessment of River Ujh has been carried out using benthic macro-invertebrates based on the Hindu-Kush Himalayan (HKH) rapid field bio-assessment protocol. Meanwhile, the assessment of water quality in the river was performed using the weighted arithmetic water quality index (WA-WQI), based on physiochemical parameters. Furthermore, the biotic indices (such as Nepalese Biotic Score (NEPBIOS), modified NEPBIOS, HKHBIOS, Stream Invertebrate Grade Number-Average Level (SIGNAL), SIGNAL 2, biological monitoring working party and biological water quality class criteria) were used for biological assessment of water quality. The water samples were collected from eight sampling stations during the month of February in year 2015. The results indicate that the overall water quality in the river was poor (i.e. not suitable for drinking), as average WA-WQI was 78.65 in the sampling month. During the analysis of micro-invertebrate occurrence, a total of 10 taxonomic groups, 36 families and 2193 individual organisms were identified. Among all organisms, the members of taxonomic groups Ephemeroptera and Trichoptera were found in abundance at all sampling stations. However, the NEPBIO score was found to be decreasing from 6.1 at first sampling stations (S1, located in upstream) to 4.8 at last (S8, located in downstream), which indicate the decline in abundance of organisms due to deterioration of water quality in the river. Therefore, it has been suggested the river water must be treated prior to use for drinking. It is recommended that biotic indices developed for bio-assessment of water bodies in the central Himalayan region can also be applied suitably to assess the water quality status in River Ujh.

Capturing forest dependency in the central Himalayan region: Variations between Oak (Quercus spp.) and Pine (Pinus spp.) dominated forest landscapes.

Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

Chemical characteristics of soluble aerosols over the central Himalayas: insights into spatiotemporal variations and sources.

In order to investigate the spatial and temporal variations of aerosols and its soluble chemical compositions of the data gap zone in the central Himalayan region, aerosol samples were collected at four sites. The sampling location were characterized by four different categories, such as urban (Bode), semi-urban site in the northern Indo-Gangetic Plain (Lumbini), rural (Dhunche), and semiarid rural (Jomsom). A total of 230 aerosol samples were collected from four representative sites for a yearlong period and analyzed for water-soluble inorganic ions (WSIIs). The annual average aerosol mass concentration followed the sequence as Bode (238.24±162.24μg/m3)> Lumbini (161.14±105.95μg/m3)> Dhunche (112.40±40.30μg/m3)> Jomsom (78.85±34.28μg/m3), suggesting heavier particulate pollution in the urban and semi-urban sites. The total soluble ions contributed to 12.61-28.19% of TSP aerosol mass. The results revealed that SO42- and NO3- were the major anion and Ca2+ and NH4+ were the major cation influencing the aerosol composition over the central Himalayas. Calcium played a major role in neutralizing aerosol acidity followed by NH4+ at all the sites. The major compound of aerosol was (NH4)2SO4 and NH4HSO4 in the central Himalayas. Clear seasonality was observed at three observation sites, with higher concentrations during non-monsoon (dry periods) and lower during monsoon (wet period), suggesting washing out of aerosol particles by heavy precipitation during monsoon. In contrast, semiarid sites did not show the clear seasonal trend due to limited precipitation. Stationary sources were predominant over the mobile sources mostly in the remote sites. Principal component analysis confirmed that the major sources of WSIIs in the region were industrial emissions, fossil fuel and biomass burning, and crustal fugitive dusts. Nevertheless, transboundary aerosol transport over the region from polluted cities from south Asia could not be ignored as indicated by the clusters of air mass backward trajectory analysis.