Wooden Panel Deterioration by Tropical Marine Wood Borers     

Harinder Rai Singh  A. Sasekumar 《Estuarine, Coastal and Shelf Science》1996,42(6):755-769

Wood destruction in test panels ofShorea leprosulawas related to the percentage of fouling, types of wood borers and the number of wood borers. The natural durability ofShorea leprosulapanels was estimated to be 4–5 months in Malaysian marine waters. A higher fouling cover resulted in lower rates of wooden panel deterioration. Larger numbers of wood borers brought about greater panel deterioration. Primary wood destruction was caused by bivalve wood borers, mainlyMartesia striata, Lyrodus pedicellatus, Bankia campanellata, Teredo furciferaandTeredo bartschi. Martesia striatawas the important wood destroying agent in the intertidal zone and, together with the shipworms, was also responsible for panel destruction in the subtidal zone.  相似文献   

19th Himalaya-Karakoram-Tibet Workshop in Niseko, Japan, July 2004     

Masaru Yoshida  S.M. Rai  S.A. Rashid  Tetsuya Sakai 《Gondwana Research》2005,8(4):626-629

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Political ecology of tiger conservation in India: Adverse effects of banning customary practices in a protected area     

Nitin D. Rai  Tor A. Benjaminsen  Siddhartha Krishnan  C. Madegowda 《Singapore journal of tropical geography》2019,40(1):124-139

Protected areas have had significant impacts on local communities primarily through the physical removal of people. In some instances, people continue to live within protected areas due to the inability of the state to evict them. The restrictions on livelihoods placed on people living inside protected areas lead to in situ displacement. We show how conservation enclosures in the Biligiri Rangaswamy Temple Tiger Reserve have produced a class of people that the state ‘lets die’ by banning customary practices such as fire use, hunting and harvesting of forest produce. Using longitudinal ethnographic, socio‐economic and ecological data, we demonstrate that conservation policy has alienated indigenous forest dwellers from their agricultural and forest‐land. The outcomes of conservation policy include dispossession through increased crop losses, reduced income from agriculture and forest produce, as well as a forest that is dominated by weeds due to fire suppression. The ban on hunting in particular has increased wildlife densities, which has enabled the state to accumulate revenues through the establishment of wildlife tourism facilities. All in all, centralized protected area governance has changed the relationships among people, forest and the state in a way that has produced adverse effects for both livelihoods and the ecosystem.  相似文献   

Investigation of Crushed Aggregate as Stemming Material in Bench Blasting: A Case Study     

Suresh Kumar Sharma  Piyush Rai 《Geotechnical and Geological Engineering》2015,33(6):1449-1463

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Role of land state in a high resolution mesoscale model for simulating the Uttarakhand heavy rainfall event over India     

P V Rajesh  S Pattnaik  D Rai  K K Osuri  U C Mohanty  S Tripathy 《Journal of Earth System Science》2016,125(3):475-498

In 2013, Indian summer monsoon witnessed a very heavy rainfall event (>30 cm/day) over Uttarakhand in north India, claiming more than 5000 lives and property damage worth approximately 40 billion USD. This event was associated with the interaction of two synoptic systems, i.e., intensified subtropical westerly trough over north India and north-westward moving monsoon depression formed over the Bay of Bengal. The event had occurred over highly variable terrain and land surface characteristics. Although global models predicted the large scale event, they failed to predict realistic location, timing, amount, intensity and distribution of rainfall over the region. The goal of this study is to assess the impact of land state conditions in simulating this severe event using a high resolution mesoscale model. The land conditions such as multi-layer soil moisture and soil temperature fields were generated from High Resolution Land Data Assimilation (HRLDAS) modelling system. Two experiments were conducted namely, (1) CNTL (Control, without land data assimilation) and (2) LDAS, with land data assimilation (i.e., with HRLDAS-based soil moisture and temperature fields) using Weather Research and Forecasting (WRF) modelling system. Initial soil moisture correlation and root mean square error for LDAS is 0.73 and 0.05, whereas for CNTL it is 0.63 and 0.053 respectively, with a stronger heat low in LDAS. The differences in wind and moisture transport in LDAS favoured increased moisture transport from Arabian Sea through a convectively unstable region embedded within two low pressure centers over Arabian Sea and Bay of Bengal. The improvement in rainfall is significantly correlated to the persistent generation of potential vorticity (PV) in LDAS. Further, PV tendency analysis confirmed that the increased generation of PV is due to the enhanced horizontal PV advection component rather than the diabatic heating terms due to modified flow fields. These results suggest that, two different synoptic systems merged by the strong interaction of moving PV columns resulted in the strengthening and further amplification of the system over the region in LDAS. This study highlights the importance of better representation of the land surface fields for improved prediction of localized anomalous weather event over India.  相似文献   

Prediction of daily modes of South Asian monsoon variability and its association with Indian and Pacific Ocean SST in the NCEP CFS V2     

Namendra Kumar Shahi  Shailendra Rai  D. K. Pandey 《Meteorology and Atmospheric Physics》2016,128(1):131-142

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Investigation of Cycle Time Segments of Dragline Operation in Surface Coal Mine: A Statistical Approach     

Mousa Mohammadi  Piyush Rai  Umesh Singh  S. K. Singh 《Geotechnical and Geological Engineering》2016,34(6):1765-1774

Dragline is highly capital intensive equipment to procure, operate and maintain in any surface mining operation. Given this, every second of operation of this capital intensive equipment is absolutely important. Improvement of even a single second in the total cycle time has a tremendous bearing on the overall performance of this equipment. In this light, the present paper is an endeavour to critically analyze the cycle time of dragline operations in a major surface coal mine in India. Rigorous statistical analysis has been performed on individual cycle time segments, of complete dragline cycle. The segmental cycle times have been found to be statistically significant and appear to be best represented by lognormal, normal and beta distributions. Furthermore, the mean time of the statistical distribution for segmental cycle time of dragline has revealed the dependence of cycle time on cut geometry and depth. Results have been illustrated in the form of figures, graphs and tables.  相似文献   

Isotopic characteristics of cryospheric waters in parts of Western Himalayas,India     

S. P. Rai  Renoj J. Thayyen  P. Purushothaman  Bhishm Kumar 《Environmental Earth Sciences》2016,75(7):600

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Snowmelt runoff and groundwater discharge in Himalayan rivers: a case study of the Satluj River,NW India     

A. S. Maurya  S. P. Rai  N. Joshi  K. S. Dutt  N. Rai 《Environmental Earth Sciences》2018,77(19):694

The Himalayas are one of the largest cryospheric systems outside the Polar Regions, and include more than 12,000 glaciers spread over an area of about 33,000 km². The Himalayan glaciers and snow packs retreating at an accelerating rate, thereby creating an alarming situation for the huge population that resides in northwestern India and southeastern Pakistan, as they depend on surface water resources in the region and rivers emanating from the Himalayas. This work attempts to quantify the contribution of different sources such as glacial/ice/snow melt and groundwater discharge to the Satluj River using the stable isotopes based hydrograph separation method at Ropar (foot hill) and Yusufpur in plain of Punjab, India. A mass balance model of three-component mixing has been engaged using the values of δ¹⁸O and electrical conductivity of the river water, and its discharge fraction, to estimate the time-varying relative proportion of each component from July 2013 to January 2014. The proportion of glacier melt was found to peak up to ~?64% at Ropar and ~?15% at Yusufpur during the wet summer months. The fraction of groundwater discharge was found to vary between 10–20% at Ropar and 25–35% at Yusufpur (Punjab plain) over time. The observed trend of d-excess (deuterium excess) values of river water also suggests that the glaciers and snow packs at higher altitudes contain a significant fraction of snow derived from vapor originating in the Mediterranean region, driven by the mid-latitude westerlies known as western disturbances.  相似文献   

2-D Crustal thermal structure along Thuadara-Sindad DSS profile across Narmada-Son lineament,central India   总被引：1，自引：0，他引：1  

S. N. Rai  S. Thiagarajan 《Journal of Earth System Science》2007,116(4):347-355

Central India is traversed by a WSW-ENE trending Narmada-Son lineament (NSL) which is characterized by the presence of numerous hot springs, feeder dykes for Deccan Traps and seismicity all along its length. It is divided in two parts by the Barwani-Sukta Fault (BSF). To the west of this fault a graben exists, whereas to the east the basement is uplifted between Narmada North Fault (NNF) and Narmada South Fault (NSF). The present work deals with the 2-D thermal modeling to delineate the crustal thermal structure of the western part of NSL region along the Thuadara-Sindad Deep Seismic Sounding (DSS) profile which runs almost in the N-S direction across the NSL. Numerical results of the model reveal that the conductive surface heat flow value in the region under consideration varies between 45 and 47mW/m². Out of which 23mW/m² is the contribution from the mantle heat flow and the remaining from within the crust. The Curie depth is found to vary between 46 and 47 km and is in close agreement with the earlier reported Curie depth estimated from the analysis of MAGSAT data. The Moho temperature varies between 470 and 500°C. This study suggests that this western part of central Indian region is characterized by low mantle heat flow which in turn makes the lower crust brittle and amenable to the occurrence of deep focused earthquakes such as Satpura (1938) earthquake.  相似文献