Lower Himalayan Region Research Articles

At the Junction Between Deep Learning and Statistics of Extremes: Formalizing the Landslide Hazard Definition

AbstractThe most adopted definition of landslide hazard combines spatial information about landslide location (susceptibility), threat (intensity), and frequency (return period). Only the first two elements are usually considered and estimated when working over vast areas. Even then, separate models constitute the standard, with frequency being rarely investigated. Frequency and intensity are dependent on each other because larger events occur less frequently and vice versa. However, due to the lack of multi‐temporal inventories and joint statistical models, modeling such properties via a unified hazard model has always been challenging and has yet to be attempted. Here, we develop a unified model to estimate landslide hazard at the slope unit level to address such gaps. We employed deep learning, combined with extreme‐value theory to analyze an inventory of 30 years of observed rainfall‐triggered landslides in Nepal and assess landslide hazard for multiple return periods. We also use our model to further explore landslide hazard for the same return periods under different climate change scenarios up to the end of the century. Our model performs excellently (with an accuracy of 0.78 and an area under the curve of 0.86) and can be used to model landslide hazard in a unified manner. Geomorphologically, we find that under climate change scenarios (SSP245 and SSP585), landslide hazard is likely to increase up to two times on average in the lower Himalayan regions (Siwalik and lower Himalayas; ≈110–3,500 m) while remaining the same in the middle Himalayan region (≈3,500–5,000 m) whilst decreasing slightly in the upper Himalayan region (≳5,000 m) areas.

Geospatial analysis of toxic metal contamination in groundwater and associated health risks in the lower Himalayan industrial region

Once known for its clean and natural environment, the lower Himalayan region is now no exception to human-induced disturbances. Rapid industrial growth in Baddi-Barotiwala (BB) industrial region has led to degradation of groundwater resources in the area. Groundwater samples were collected from 37 locations to study the groundwater chemistry, geospatial variation of 15 toxic metals in groundwater, source apportionment, metals of concern and associated health risks in the region. The results showed rock dominated hydrogeology with decreasing order of anion and cation abundance as HCO3− > Cl− > SO42− > NO3− > Br− > F− and Ca+ > Na+ > Mg2+ > K+ > Li+ respectively. Concentrations of Iron (BDL-3.6 mg/l), Nickel (BDL-0.023 mg/l), Barium (0.22–0.89 mg/l), Lead (0.0001–0.085 mg/l) and Zinc (0.006–21.4 mg/l) were found above the permissible limits at few locations. Principal component analysis (PCA) and coefficient of variance (CV) showed both geogenic and anthropogenic origin of metals in groundwater of the BB industrial region. A consistent concentration of Uranium was detected at all the sampling locations with an average value of 0.0039 mg/l and poor spatial variation indicating its natural presence. Overall, non-carcinogenic (N-CR) risk in the study area via oral pathway was high for adults and children (Hazard Index > 1) with geogenic Uranium as the major contributor (Hazard Quotient > 1) followed by Zinc, Lead and Cobalt. Carcinogenic (CR) risk in the region was high for adults having mean value above the threshold (1E-04) with Nickel and Chromium as the metals of major concern. Spatial variation of health risks was overlayed on village boundaries of the region to identify the potential industrial sources of the metals of major concern. The results highlight the need for immediate remediation of groundwater resources in order to achieve a harmonious coexistence between industrialization and human well-being.

Glacial retreat delineation using machine and deep learning: A case of a lower Himalayan region

Glacial retreat delineation using machine and deep learning: A case of a lower Himalayan region

Assessment of Welfare in Transhumance Yak Hybrids (Chauris) in the Lower Himalayan Region of Nepal

In order to develop a yak/chauri-specific welfare assessment protocol, we sent a set of 31 potential welfare measures to 120 Nepalese experts and asked them to identify the measures that they thought would be useful and propose additional useful measures. Eighty-three experts responded, with 13 measures being identified by >50% of respondents as likely to be useful. These thirteen measures plus one new measure (hematology) were included in an assessment protocol that was tested in the second phase of this study in five chauri herds in two districts in northern Nepal. Animal-based evaluations along with sampling for mastitis, intestinal parasites, and hematology were undertaken during or just after morning milking. Resource- and record-based measures were assessed through structured interviews, with verifications on-site where possible. No chauris exhibited poor body conditions, skin injuries, significant locomotion issues, or significant subclinical mastitis. Fecal testing suggested a high prevalence of intestinal parasites at the herd level, while blood testing suggested no evidence of hematological abnormalities. However, for both results, we need more data to use these effectively as measures of welfare. The resource-based assessment revealed significant challenges across all resources, and veterinary services were reported as being inadequate. A high estimated annual mortality rate (10–21%) needs further investigation. This protocol provided a useful start towards developing a welfare assessment protocol for yak/chauri and identified issues that need addressing to optimize chauri welfare.

Spatial variation in iodine content with relation to soil physicochemical properties in lower Himalayan region

Topography of a place has a significant impact on soil characteristics that ultimately influence soil iodine levels. Lower Himalayan region (LHR) in Pakistan has a wide range of climatic and geological variations. Hence, an investigation was conducted to analyze the iodine concentration and other physicochemical properties of soils in two LHR districts, Haripur and Mansehra. Spatial analysis indicated a decrease in iodine levels in the mountainous regions in comparison to the flat portions of LHR. Soil samples obtained from different locations across Haripur had a stronger affinity for iodine due to variations in solubility and adsorption of iodine to soil clay components, which can be attributed to lower pH, higher organic matter, and a higher cation exchange capacity (CEC). In contrast to the plains of Haripur, elevated locations in the Mansehra district had decreased levels of iodine, along with a higher soil pH and reduced soil organic matter. The soil erosion and depletion of soil micronutrients in the hilly region of Mansehra may be attributed to the unfavorable soil conditions and excessive precipitation. Presence of clay, iron (Fe), and aluminum (Al) in the soil led to a rise in iodine levels. Iodine concentrations exhibited an inverse relationship with soil acidity. Study revealed a direct correlation between soil iodine levels and their cation exchange capacity (CEC) and clay content. This study aims to gather fundamental data for the chosen regions of LHR to address illnesses caused by iodine deficiency.

Phytochemical Screening of Nyctanthes arbor-tristis Plant Extracts and Their Antioxidant and Antibacterial Activity Analysis.

Nyctanthes arbor-tristis, alias "Vishnu Parijat," is a medicinal plant used to treat various inflammation-associated ailments and to combat innumerable infections in the traditional system of medicine. In the present study, we collected the samples of N. arbor-tristis from the lower Himalayan region of Uttarakhand, India, and carried out their molecular identification through DNA barcoding. To examine the antioxidant and antibacterial activities, we prepared the ethanolic and aqueous extracts (from flowers and leaves) and performed their phytochemical analysis by using different qualitative and quantitative approaches. The phytoextracts showed marked antioxidant potential, as revealed by a comprehensive set of assays. The ethanolic leaf extract showed marked antioxidant potential towards DPPH, ABTS, and NO scavenging (IC50 = 30.75 ± 0.006, 30.83 ± 0.002, and 51.23 ± 0.009 μg/mL, respectively). We used TLC-bioautography assay to characterize different antioxidant constituents (based on their Rf values) in the chromatograms ran under different mobile phases. For one of the prominent antioxidant spots in TLC bioautography, GC-MS analysis identified cis-9-hexadecenal and n-hexadecanoic acid as the major constituents. Furthermore, in antibacterial study, the ethanolic leaf extract showed marked activity against Aeromonas salmonicida (113.40 mg/mL of extract was equivalent to 100 μg/mL of kanamycin). In contrast, the ethanolic flower extract showed considerable antibacterial activity against Pseudomonas aeruginosa (125.85 mg/mL of extract ≡100 μg/mL of kanamycin). This study presents the phylogenetic account and unravels the antioxidant-related properties and antibacterial potential of N. arbor-tristis.

Analysis of the relationship among land surface temperature (LST), land use land cover (LULC), and normalized difference vegetation index (NDVI) with topographic elements in the lower Himalayan region

Land Surface Temperature (LST) affects exchange of energy between earth surface and atmosphere which is important for studying environmental changes. However, research on the relationship between LST, Land Use Land Cover (LULC), and Normalized Difference Vegetation Index (NDVI) with topographic elements in the lower Himalayan region has not been done. Therefore, the present study explored the relationship between LST and NDVI, and LULC types with topographic elements in the lower Himalayan region of Pakistan. The study area was divided into North-South, West-East, North-West to South-East and North-East to South-East directions using ArcMap 3D analysis. The current study used Landsat 8 (OLI/TIRS) data from May 2021 for LULC and LST analysis in the study area. The LST data was obtained from the thermal band of Landsat 8 (TIRS), while the LULC of the study areas was classified using the Maximum Likelihood Classification (MLC) method utilizing Landsat 8 (OLI) data. TIRS collects data for two narrow spectral bands (B10 and B11) with spectral wavelength of 10.6 μm–12.51 μm in the thermal region formerly covered by one wide spectral band (B6) on Landsat 4–7. With 12-bit data products, TIRS data is available in radiometric, geometric, and terrain-corrected file format. The effect of elevation on LST was assessed using LST and elevation data obtained from the USGS website. The LST across LULC types with sunny and shady slopes was analyzed to assess the influence of slope directions. The relationship of LST with elevation and NDVI was examined using correlation analysis. The results indicated that LST decreased from North-South and South-East, while increasing from North-East and South-West directions. The correlation coefficient between LST and elevation was negative, with an R-value of −0.51. The NDVI findings with elevation showed that NDVI increases with an increase in elevation. Zonal analysis of LST for different LULC types showed that built-up and bare soil had the highest mean LST, which was 35.76 °C and 28.08 °C, respectively, followed by agriculture, vegetation, and water bodies. The mean LST difference between sunny and shady slopes was 1.02 °C. The correlation between NDVI and LST was negative for all LULC types except the water body. This study findings can be used to ensure sustainable urban development and minimize urban heat island effects by providing effective guidelines for urban planners, policymakers, and respective authorities in the Lower Himalayan region. The current thermal remote sensing findings can be used to model energy fluxes and surface processes in the study area.

Rainfall Wet Spells Variability Across Temperature Mean‐Change Years in the Northwestern Himalayan Region

AbstractTemperatures have risen at a faster rate across various mountainous regions around the world. A study of the changing rainfall patterns and their spatiotemporal variability is critical for agricultural, water resource, and hydrological planning and management. The goal of this research is twofold: first, using functional data analysis climate change hotspots are determined, which in turn identified most temperature increases in high elevations. Second, these hotspots are utilized to investigate the impact of temperature changes on the frequency of extreme rainfall events in this Northwestern Himalaya region. Our study observed that the frequency of rainfall extremes, such as, at the 90th, 95th, and 99.99th percentile values, is found to be increasing mostly in lower Himalayan regions. A warmer atmosphere leads to heavy precipitation events as the capacity of air to hold moisture increases with the increase in temperature. The continuous temperature rise possibly indicates an increase in extreme rainfall events in the region. Further, this study reports an interesting finding that can help us better understand the impact of climate change in the region: the frequency of shorter wet spells has increased around the recent mean‐change year, whereas the frequency of long spells has reduced. The frequency of longest wet spells shows a decrease across all seasons, leading to drought in the higher altitude region, whereas the short‐wet spell frequency has increased in the lower altitude regions. Insight into the changing patterns of rainfall is crucial for hydrological and agricultural management.

Variation of annual indoor and outdoor gamma dose rate in the lower Himalayan region of Reasi district of Jammu and Kashmir, India

The exposure from natural sources of radiation imparts a major contribution to doses, both due to external and internal exposures that would be received by members of public, and its levels rely upon the lithology, altitude, and building construction materials. The measurement results of ambient indoor and outdoor radiation levels at 28 locations (villages) of Reasi district, Jammu and Kashmir, India, are presented. The ambient radiation levels were measured utilizing a portable gamma survey meter. For the outdoor environment, the minimum and maximum gamma dose rates were 0.09 and 0.29 μSv/h, whereas, at indoors, the minimum and maximum gamma dose rates were 0.08 and 0.22 μSv/h, respectively. Impact of elevation (height above sea level) on radiation levels has been investigated, and it revealed a weak positive relationship with altitude. Effects of lithology on indoor and outdoor gamma dose rates have likewise been investigated. The average annual effective dose value due to ambient radiation levels was well within the world average values.

Quantification of rosmarinic acid from different plant species of lower Himalayan region and expression analysis of underlying L-Phenylalanine pathway.

This study adopts a very effective high-performance liquid chromatography (HPLC) technique for the quantitative determination of rosmarinic acid (RA) and PCR-based amplification of biosynthetic key regulators in Isodon rugosus, Daphne mucronata, and Viburnum grandiflorum from the lower Himalayan regions. Rosmarinic acid is engaged in a variety of biological processes and has significant industrial significance. In this study, it was identified from crude methanolic extract using thin-layer chromatography with a standard, and its content was quantified using HPLC without interrupting spikes using a mixture of methanol and deionized water containing acetonitrile (70:30 v/v) and acetic acid (0.1% v/v) at UV 310 nm absorption. We used RT-PCR to identify cDNAs encoding PAL, C4H, and RAS, and Image J's semi-quantitative analysis to quantify the expression levels of genes involved in RA production from chosen plant material. The highest levels of PAL, C4H, and RAS were detected, by band intensity, in the leaves and flowers of I. rugosus, which also exhibited a substantial quantity of RA. However, in V. grandiflorum and D. mucronata the transcript of the given genes was low. The concentration of RA ranged from 187.7 to 21.2mg g-1 for I. rugosus, 17.42 to 5.42 mg g-1 for V. grandiflorum, and 15.19 mg g-1 for D. mucronata. This study demonstrated that the method for quantifying RA from a crude methanolic extract was effective, indicating that I. rugosus might be used as an indigenous alternative source of RA.

Hydrological modelling through SWAT over a Himalayan catchment using high-resolution geospatial inputs

The concerns of water availability have been increasing due to population explosion, rapid industrialization, and other anthropogenic activities. This urges for an accurate estimation of streamflow at the river basin scale, which is typically carried out by the application of rainfall-runoff models. Though numerous models exist in hydrology literature, their efficiency over the mountainous catchments is generally observed to be poor, mostly due to the lack of high-quality data over such regions. This study presents an application of the widely used soil and water assessment tool (SWAT)-based hydrological modelling using high-resolution geospatial inputs over the Tehri reservoir catchment (India) located in the lower Himalayan region. The Resourcesat-2 Linear Imaging Self-Scanning System (LISS)-IV imageries of land use/land cover (LULC) and the Cartosat-1 digital elevation model (DEM) are procured from National Remote Sensing Centre (NRSC), Indian Space Research Organization (ISRO), India. The LULC and DEM have a spatial resolution of 5.8 m and 2.5 m, respectively. SWAT model is applied for a duration of 12 years (2006-2017) with 2006, 2007-2013 and 2014-2017 as the warm-up, calibration and validation periods, respectively. The results reveal an excellent performance of the model in streamflow simulation. The efficacy measures viz., Nash–Sutcliffe efficiency (NSE) and Coefficient of determination (R2) are obtained to be 0.83 and 0.84, respectively. The information reported in this study will be helpful to the water resources engineers for hydrologic modelling over the mountainous catchments.

Assessing the trends and drivers of land use land cover change in district Abbottabad lower Himalayan Region Pakistan

Land Use Land Cover (LULC) dynamics and the associated drivers are vehemently debated issues among scientific community due to its significant impact on global scale. Therefore, this study aimed to investigate the major trends and drivers influencing LULC change in District Abbottabad, Pakistan. Mixed method approach comprising of remote sensing, Geographic Information System (GIS) and household survey were employed to collect data from 130 households. Descriptive data was analyzed through index-based ranking. Further logistic regression was employed to examine the impact of perceived drivers of LULC change. Ranking of major perceived and proximate drivers identified were unplanned urbanization, natural conditions, agricultural decline and increase infrastructure. While population growth, lack of financial resources, poor marketing and weak governance were identified as underlying drivers of LULC change. Similarly, findings of GIS data revealed massive increase in built-up (3.12%) areas and urbanization at the expense of agricultural and bare land (−15.7%) between 1987 and 2019.

Investigation of thermal comfort and adaptation among the residents of cold climate in the lower Himalayan region of eastern India

Thermal comfort standards are required for overall indoor satisfaction and energy conservation. Even though the lower Himalayan region of Darjeeling has seen rapid growth in population due to its temperate type of climate, and thus resulting in manifold construction of concrete buildings, very few research on the built environment are reported from the region. In this paper, the author has discussed the yearlong thermal comfort study conducted in a naturally ventilated 3-storey un-insulated concrete building located at lower Himalayan region of Darjeeling, India. The mean indoor operative temperature were 16.7°C, 19.0°C and 22.3°C, the clothing insulation were 0.94 clo, 0.78 clo and 0.57 clo and the mean Griffiths’ comfort temperature were 18.1°C, 19.6°C and 22.4°C during the cool, moderate and warm seasons, respectively. Seasonal and gender-wise differences are reported in the paper. A logistic regression is presented to show the variation of single and multiple layers of clothing used by subjects to adapt with the plummeting temperature. A modification in the comfort standards for the region with lower and upper limits as 16.2°C and 23.3°C is also proposed.

Assessing the predictive efficacy of six machine learning algorithms for the susceptibility of Indian forests to fire

Increasing numbers and intensity of forest fires indicate that forests have become susceptible to fires in the tropics. We assessed the susceptibility of forests to fire in India by comparing six machine learning (ML) algorithms. We identified the best-suited ML algorithms for triggering a fire prediction model, using minimal parameters related to forests, climate and topography. Specifically, we used Moderate Resolution Imaging Spectroradiometer (MODIS) fire hotspots from 2001 to 2020 as training data. The Area Under the Receiver Operating Characteristics Curve (ROC/AUC) for the prediction rate showed that the Support Vector Machine (SVM) (ROC/AUC = 0.908) and Artificial Neural Network (ANN) (ROC/AUC = 0.903) show excellent performance. By and large, our results showed that north-east and central India and the lower Himalayan regions were highly susceptible to forest fires. Importantly, the significance of this study lies in the fact that it is possibly among the first to predict forest fire susceptibility in the Indian context, using an integrated approach comprising ML, Google Earth Engine (GEE) and Climate Engine (CE).

Evaluation of Essential Oil Extracted from Acorus calamus Rhizomes and Leaves

Abstract-Essential oils are volatile complex compounds which are characterized by a strong odour and are formed naturally by aromatic plants as secondary metabolites. The practical value of essential oils in daily life is explored through the study of numerous physicochemical characteristics (Parthiban et al., 2011). Physicochemical characteristics indirectly influence the quality of the essential oils. The commercial importance of oils mostly depends on these physicochemical characteristics, which provide baseline data to determine its suitability for consumption. Therefore, the present study was taken to evaluate characteristics of the essential oil extracted from the leaves and rhizomes of Acoruscalamus which is a wild aromatic plant species growing in the lower Himalayan region and the essential oil extracted from the plant is used frequently in skin care and aromatherapy to uplift mood and relieve stress. Essential oil was extracted from both rhizome and leaves (Ac R and Ac L) of Acoruscalamus and are analysed for characteristics like yield, specific gravity, viscosity, refractive index, acid number, saponification value, etc. Results indicated that that essential oil Ac R is more superior to Ac L in quality enhancing its commercial importance and can be taken up for further studies.

Analyzing the decadal transformation of the LULC from tillage to a townified area in the Lower Himalayan Region, Pakistan

Analyzing the decadal transformation of the LULC from tillage to a townified area in the Lower Himalayan Region, Pakistan

Performance analysis of clean energy using geothermal earth to air heat exchanger (GEAHE) in Lower Himalayan Region – Case study scenario

Energy demand in India at present is fulfilled by non-renewable sources despite the prime geographical location of some states. Geothermal energy is the renewable energy within the earth’s interior will be used for various purposes. In this paper, an attempt has been made to use the renewable source of energy for sustainable development. The thermal performance of earth to air tunnel heat exchanger for passive winter preheating and summer cooling has been evaluated. The effect of an operating parameter such as pipe/tube material, soil thermal conductivity and air velocity on the thermal performance of earth to air heat exchanger (GEAHE) to be used in Lower Himalayan Region has been analyzed. The results indicate that the exit temperature drops with an increase in underground pipe/tube length during summers and decreases during winters. However, the mean efficiency increases with increase in underground pipe/tube length. Maximum efficiency of 85.6% and 87.7% is achieved during summer and winter respectively at an air velocity of 0.5 m/s for an underground pipe of 60 m length. Also, the maximum average cooling potential is 14.81 kWh during summer for earth air tunnel heat exchanger at underground pipe length of 60 m and at a velocity of 0.5 m/s. Similarly, the maximum average heating potential is 27.7 kWh during winter for same operating parameters; which is higher as compared to summers. Thus the results indicate that earth air tunnel heat exchanger is more effective during winter in Lower Himalayan Region. The results demonstrate that geothermal energy stored in a Lower Himalayan Region of India can be a driving force for sustainable development.

Identification and characterization of colistin-resistant E. coli and K. pneumoniae isolated from Lower Himalayan Region of India

Multidrug resistance is one of the worldwide public health concerns. Water represents the most suitable environment, for the exchange of antibiotic resistance genes among pathogenic to non-pathogenic bacteria. Therefore, we aimed to screen the presence of blaNDM-1, blaTEM, blaSHV, blaCTX-M and mcr1–5 genes among water samples from different locations of Lower Himachal Pradesh. We examined the genotypic incidences of blaNDM-1, blaTEM, blaSHV, blaCTXM and mcr1–5 by polymerase chain reaction. Survivability assay, fitness cost assay and biofilm assay were performed for phenotypic characterization. The presence of blaNDM-1 and its related variants were analysed and confirmed by sequencing-based approaches. A total of 73 bacterial strains were identified on M-lauryl sulphate agar medium. Out of 73 colistin-resistant isolates, 34 were E. coli and 39 were K. pneumoniae. Out of 34 samples, 2 (5.8%), 2 (5.8%), 5 (14.7%), 5 (14.7%) and 4 (11.76%) E. coli were blaTEM, blaSHV,blaCTXM-1, blaCTXM-2 and blaCTXM-15 positive, respectively. Among 39 K. pneumoniae, 15 (38.4%), 6 (15.3%), 10 (25.6%), 9 (23.07%) and 10 (25.6%) were blaTEM, blaSHV, blaCTXM-1, blaCTXM-2 and blaCTXM-15 positive, respectively. Interestingly, we observed one E. coli (HG4) isolate with both blaNDM-1 and mcr-1 gene. Further analysis showed HG4 isolate has lesser survivability on the cotton swab, long lag phase and less biofilm production compared to colistin-sensitive isolates. Detection of E. coli with blaNDM-1 and mcr-1 in this geographical region is an alarming signal for tourists, community, health workers and policymakers. Hence, it is utmost important to take appropriate measures to control the dissemination of antibiotic resistance gene in such pristine locations.

Comparative assessment of polyphenolics’ content, free radicals’ scavenging and cellular antioxidant potential in apricot fruit

Natural antioxidants possess health beneficial properties and are being substantially used in foods, cosmetics and pharmaceutical products. Polyphenolics content, antioxidant activity and HepG2 liver cancer cells’ inhibition potential were determined and compared in the fruit of apricot cultivars collected from lower Himalayan region of Pakistan using standard analytical procedures. Comparatively, fruit of AP3 cultivar had highest levels of total phenolics and total flavonoids contents (220.5 ± 15.9 mgGAE/100 g and 382.0 ± 18.0 mgQE/100 g, respectively) on fresh weight basis. Fruit of the same cultivar had maximum DPPH scvenging potential (94.24 ± 4.55%), oxygen radicals absorbance capacity at 4.71 ± 0.12 mMolTE/100 g and inhibition of HepG2 cancer cells (45.80 ± 4.01 µMolQE/100 g). Though, fruit of AP4 cultivar was rich in vanillic acid, caffeic acid, vanillin, epi-catechin and quercetin, but had relatively low antioxidant and anticancer potential. Disparities in the phytochemical composition and properties of apricot fruit are attributed to genetic differences and growing conditions. Total phenolics, total flavonoids and caffic acid depicted highly significant positive association (˃90%) with ORAC, CAA and FRAP. Our findings suggest that being a rich source of health beneficial secondary metabolites, apricot fruit of Himalayan region of Pakistan could contribute considerably in socio-economic development of the local communities and as a functional food in regional and global markets.

Water Relations of Two Adjacently Growing Tree Species Shorea Robusta Gaertn-and Pinus Roxburbhii Sarg-in the Lower Himalayan Region

Water potential (predawn and mid day), water potential components (osmotic potential at full and zero turgor, relative water content), soil water potential and leaf conductance were measured for two adjacently growing tree species Shorea robusta Gaertn and Pinus roxburghii Sarg. at an elevation of 1370m. The stands were open and the density of S. robusta was 212 trees/ha and of P. roxburghii was 141trees/ha. Presence of high number of saplings indicates both the species were regenerating well in the site despite human disturbance. S. robusta maintained relatively high predawn water potential even in summers (above -0.50MPa) and P. roxburghii showed low predawn water potential in early summer and summer season (above-1.4 MPa). P. roxburghii maintained a relatively small daily change in water potential during early summer and summer season (0.33MPa and 0.27MPa) indicating greater ability of the species to close its stomata as drought intensifies. The values of osmotic potential at full and zero turgor remained more or less constant for S. robusta from monsoon to winter and then declined during early summer. P. roxburghii showed a gradual decline in osmotic potential values from monsoon to winter season. Chir-pine has the ability of invade and grow on sites that are water stressed which can be related to its capacity to show high osmotic adjustment.. The most negative values of soil water potential were in early summer in both years. The morning and afternoon conductance was lowest during early summer and highest in autumn season.