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Species assemblages are influenced by trophic and intraguild interactions, which may be competitive, facilitative, or neutral. These interactions vary in relative importance depending on resource availability. We assessed the nature of interactions among six carnivore species (Ursus arctos, Panthera uncia, Vulpes vulpes, Mustela altaica, and Martes foina) and their prey (Capra sibirica, Pseudois nayaur, Hemitragus jemlahicus, Moschus leucogaster, Ochotona sp., and Rodentia sp.) by examining their spatial–temporal overlaps using camera‐trap data gathered between 2016 and 2019 from the resource‐limited landscapes of the high Himalayas. We examined fine scale pairwise spatial interaction using multi‐species occupancy method and temporal overlap using time activity kernel densities function. Carnivore species showed relatively high spatio‐temporal overlap. We found spatial avoidance between two pairs and temporal avoidance between four out of 15 pairs. Contrary to our expectation that carnivore species would segregate due to competition in a resource‐poor environment, our results showed that they generally showed significant co‐occurrence and appeared to track their prey's activity. Our findings highlight the potentially overriding role of prey availability in influencing carnivore species occurrence in resource‐poor landscapes. [ABSTRACT FROM AUTHOR]

Kathmandu and its surrounding region were rocked recently by a devastating earthquake on April 25, 2015. This is the largest earthquake that has occurred in this region since the past eight decades. This earthquake was recorded on strong motion stations located about 470-522 km away from its epicenter. Records of accelerographs from these stations have been used to determine the location of this earthquake using hypo71 algorithm given by Lee and Lehr (HYPO71, a computer program for determining hypocenter, magnitude and first motion pattern of local earthquakes. US Geological Survey Open file report, 100, ). The recorded accelerograms have been corrected for site effects using site amplification curve obtained from ambient seismic noise recorded at each station. Site effect has been computed using H/V ratio method given by Nakamura (Q Rep RTRI 30(1):25-33, ) using ambient noise data. The corrected record is further used to obtain source displacement spectra. The source spectrum obtained from strong motion data is compared with theoretical source spectrum obtained from Brune's (J Geophys Res 75:4997-5009, ) model for the horizontal components. The long-term flat level and corner frequency from source displacement spectra are used to calculate stress drop, source radius and seismic moment of this earthquake. The present study indicates that the Nepal earthquake originated 12.0 km below the epicenter located at 27.93°N, 84.70°E. The source radius, stress drop and seismic moment of this earthquake estimated from source displacement spectra are 44.13 ± 3.85 km, 18.68 ± 5.93 bars and 3.53 ± 0.28 × 10 dyne cm, respectively. [ABSTRACT FROM AUTHOR]

The slopes of western Lesser Himalaya (at Sangaldhan Block of Udhampur near Ramban, Jammu and Kashmir India) are being severely affected by tectonic and erosional activities. These activities result in deposit of a thick cover of rock fragments and overburden just above the hard rock. The thickness of overburden cover has directly affected the stability of slope in the study area, though the traditional stability estimation techniques, rock mass rating and slope mass rating, rate this area as moderately stable which does not represent the real stability condition. In this research work, the geotechnical and geophysical surveys have been carried out to reckon the slope stability conditions more accurately as compared to traditional slope stability estimation techniques. A new rating, new slope mass rating, is developed, which gives a better picture of the stability of slopes. It incorporates a new parameter of overburden thickness profile, along with slope angle and other associated factors on the slopes of the mountainous terrains. The vertical electrical sounding surveys were conducted for the demarcation of rock-overburden interface and for determining the overburden cover. This new classification depicts an increase of 12.84 % in unstable slope areas giving a better assessment and factual picture of slope stability in our study area. This study also enumerates the importance of geophysical applications in slope stability studies. The research work is applicable in mountainous terrains such as Himalaya, and the major component of the application is the orientation of overburden or the profile of thickness in relation with slope of surface. [ABSTRACT FROM AUTHOR]

The S-wave Fourier amplitude spectra from the strong-motion network data in the Himachal region of the northwest Himalaya are used to estimate site amplification and 5-wave attenuation (Q&bgr;). For this analysis, 60 three-component records were used from eight earthquakes with magnitudes ranging from M 3.4 to 5.4, recorded at 13 stations over a hypocentral distance range of R = 9-48 km. The characteristics of the site amplification are analyzed using horizontal-to-vertical (H/V) Fourier spectral ratios of the S phase of the time history. The average amplification is close to unity except in a narrow frequency range of 2-4 Hz. The overall behavior of the H/V ratio is consistent with local geological conditions of the study region. The 5-wave quality factor Q(f) is estimated as 103f0.66 for 0.2 ≤ f ≤ 20 Hz, and the validity is checked by computing path attenuation functions derived from the new Q(f). The estimated Q(f)is also compared with results from previous studies of Q for the Himalayan region. [ABSTRACT FROM AUTHOR]

It has now been well established that the depth of bedrock is a key parameter in assessing the impact of local site conditions on seismic hazard analysis. Where conventional geotechnical testing like standard penetration test (SPT) or cone penetration test (CPT) requires a far greater cost and manpower to be used for such purposes, geophysical testing like ground-penetrating radar (GPR) and multichannel analysis of surface waves (MASW) may provide the researchers with more viable options to achieve conclusive evidence on bedrock depth. Application of geophysical techniques has become more and more extensive and advanced in many geo-morphological studies since the early 2000s. Geophysical techniques require less time and effort, and the easy processing of the obtained data is the primary reason for their popularity. However, due to variability in subsoil mechanical properties, wave attenuation and dispersion and diverse geological boundary conditions, the results obtained through geophysical techniques are often ambiguous and non-unique. The interpretation of the obtained data also requires skill and experience, as the range may vary widely and more often than not consensus is difficult to achieve. In this paper, an endeavor has been made to coalesce the results of two widely used geophysical techniques, namely GPR and MASW to derive more conclusive evidence for the detection of bedrock depth in a part of Garhwal Himalayas. The study area comprises of two different cities of Uttarakhand, India. Both the sites possess different geo-morphological attributes and thus prove to be a perfect platform to conduct the experimentations. Both GPR and MASW testing have been performed and results are shown in graphical format. A comparison of the GPR survey with a conventional geotechnical testing (SPT) is also presented here. This study shows that GPR and MASW can provide complementary results in estimating bedrock depth. [ABSTRACT FROM AUTHOR]