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Predicting the upper stem diameters and volume of a tropical dominant tree species

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Journal of Forestry Research 2022年第6期33卷 1725-1737页

作者： Sunita Ulak Keshav Ghimire Rabindra gautam Shes Kanta Bhandari krishna Prasad Poudel Yajna Prasad Timilsina Dhirendra Pradhan Thakur Subedi Forest Research and Training Centre KathmanduNepal Institute of Forestry Tribhuvan UniversityKathmanduNepal School of Biological Sciences The University of Western AustraliaPerthAustralia Department of Forestry Mississippi State UniversityMississippi StatePO Box 9681Starkville 39762USA

Predicting upper stem diameters and individual tree volumes is important for product quantification and can provide important information for the sustainable management of forests of important commercial tree species(Shorea robusta)in *** aim of this study was to develop a taper equation for ***-four trees were selected and felled in the southern low land of Nepal.A mixed effect modelling approach was used to evaluate 17 different taper functions.‘Leave-one-out cross-validation'was used to validate the fitted taper *** variable exponent taper function best fitted our data and described more than 99%of the variation in upper stem *** also showed significant effects of stand density on tree *** tree volume prediction using the local volume model developed in this study was more accurate compared to the volume predicted through the taper function and existing volume *** taper function developed in this study provides the benefit of predicting upper stem diameter and can be used for predicting volume to any merchantable height of individual *** will have implications in estimates of volume,biomass,and carbon and thus may be a potential supporting tool in carbon trade and revenue generation.

关键词： Mixed-model approach Shorea robusta Taper Volume Nepal

Mineralogy and whole-rock geochemistry of the Oligocene Barail Group of rocks of Belt of Schuppen,Northeast India:Implications for tectono-provenance and paleo-weathering

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Acta Geochimica 2024年第5期43卷 904-932页

作者： Manash Pratim Gogoi Yunpeng Dong Pradip Borgohain Devojit Bezbaruah Arvind Pandey Yadav krishna Gogoi Garima Konwar gautam Raj Bawri Bubul Bharali Department of Petroleum Technology Dibrugarh UniversityAssam 786004India Department of Geology Northwest UniversityXi’an 710069China Department of Applied Geology Dibrugarh UniversityAssam 786004India Department of Statistics Central University of RajasthanAjmer 305817India Department of Geology Mizoram UniversityAizawlMizoram 796004India Department of Geology Pachhunga University CollegeAizawlMizoram 796001India

The petrographic and geochemical attributes of the Oligocene Barail Group of rocks are used to decipher the likely source area(s)or tectonic domains,as this sequence of rocks was deposited in a foreland basin governed by orogenic domain,namely the North-east Arunachal *** river system that gave rise to the Brahmaputra River(Yarlung-Tsangpo),which flowed through several tectonic domains of the Himalayan ranges,primarily from BomiChayu,Gangadese Granitoid,Higher Himalayan Leucogranites,and Namche Barwa into the proto Bengal Basin now a part of Assam Arakan Basin and Naga Schuppen Belt,was the main source of the sandstone formation of the Barail *** purpose of sandstone petrography,which combines modal analysis with XRF(Major Oxides)and HR-ICPMS(Trace&Rare Earth Elements)research,is to identify the type of source rock(s),their weathering pattern,and its paleo-environmental *** sandstones were formed from recycled orogen and include lithic and sublithic arenite variants with advanced texture and chemical *** sediments were felsic(Th/Co:1.38,Cr/Th:9.78,La/Lu:11.58,Th/Sc:0.99,Eu/Eu*:0.66,La/Sc:3.05,La/Co:4.18),with contributions from intermediate source rocks and low-rank metamorphics deposited in an active continental margin to a continental island arc *** conditions impacted the sediments of Barails,characterised by being warm and semi-humid to humid which resulted in moderate to a high degree of chemical weathering,as shown by weathering indices like CIA(79.14),PIA(85.47),CIW(86.9),WIP(32.50),ICV(0.71),and Th/U(6.03),which were further additionally supported by C-Value(1.01),PF(1.20),Sr/Cu(2.04),and Rb/Sr(0.97).

关键词： Belt of Schuppen Barail Group Sandstone Petrography Geochemistry Provenance Tectonic setting

Fire-induced carbon emissions from tropical mixed broad-leaved forests of the Terai–Siwalik region,central Nepal

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Journal of Forestry Research 2021年第6期32卷 2557-2565页

作者： krishna Bahadur Bhujel Rejina Maskey Byanju Ambika Pgautam Ramesh Prasad Sapkota Udhab Raj Khadka Central Department of Environmental Science Tribhuvan UniversityKathmanduNepal Kathmandu Forestry College Tribhuvan UniversityKathmanduNepal

Forest fires are one of the major environmental issues *** Nepal,substantial amounts of forest biomass and carbon are lost due to ***’s high value lowland forests are particularly vulnerable to ***,there are limited studies on the estimation of biomass loss and carbon emissions due to ***,this research addresses the information gap in the tropical mixed broad-leaved forests of Nawalparasi *** forests were divided into three strata:Lower Tropical Sal Mixed Broad-leaved Forest,Hill Sal Forest and Riverine Forest,and from these four community-managed forests were selected for estimating above ground ***-two sample plots were set out for above ground biomass estimation in burnt and non-burnt *** fire incidences from 2001 to 2017 were acquired from the MODIS fire *** biomass and carbon emissions were estimated using standard allometric *** fuel fraction consumed during the fire was estimated through field surveys during the forest fire *** results show that every year,over 3158 ha of forests are burnt,resulting in some 1108 tons of carbon emissions,equivalent to approximately 4066 t CO_(2),2581 t CO and 1474 t *** the forests,the Hill Sal Forest was more vulnerable to *** management strategies,therefore,should include construction of fire lines and conservation ponds along with capacity building and raising awareness among local communities and stakeholders.

关键词： Atmosphere Biomass density Burnt area Carbon emission Greenhouse gases

Effect of Altitude and Maturity Stages on Quality Attributes of Mandarin (Citrus reticulata Blanco)

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American Journal of Plant Sciences 2016年第6期7卷 958-966页

作者： Pradeep Raj Rokaya Dilli Ram Baral Durga Mani gautam Arjun Kumar Shrestha krishna Prasad Paudyal Agriculture and Forestry University (AFU) Rampur Nepal National Agricultural Research Institute (NARI) NARC Khumaltar Nepal

Mandarin (Citrus reticulata Blanco) is a premier fruit crop which ranks in first position of the total fruit industry in Nepal. Studies were conducted to assess the maturity indices and quality parameters of mandarin at three altitudes i.e. 1300 m·asl, 1000 m·asl, and 700 m·asl with six maturity stages i.e. 11 Oct, 21 Oct, 31 Oct, 10 Nov, 20 Nov, and 30 Nov. The most important and reliable judging criteria of fruit maturity in mandarin i.e. fruit weight, external fruit colour, firmness, TSS, acidity, and TSS/Acid ratio, and vitamin C were experimented. The experiment results revealed that 1000 m·asl location was showed the highest fruit weight (104.9 g) and juice percentage (55.23) followed by 1300 m·asl altitude (99.5 g and 53.75% respectively) at 20th of November. The maturity advanced at lower altitude with 50 percent yellow orange rind colour, 10.98 TSS/acid ratio and 4 kg/cm2 firmness from 10th November at lower altitudes whereas it was appeared in 20th November at higher altitudes. The TSS/acid ratio was significantly higher (10.98) in the fruits of 700 m·asl as compared to 1300 m·asl (9.76) on 10th November, however, on 20th November 1300 m·asl showed the highest ratio (17.76). The fruit weight, juice content, TSS was found in increasing trends up to 20 November and then showed constant and decreasing trend. However, TA, firmness and vitamin C were showed in decreasing trends with time. The 1000 - 1300 m·asl was the best location for the mandarin production and 10-20 November was the best period for the mandarin harvesting for optimum maturity.

关键词： Maturity Physico-Chemical Quality Parameters Firmness Total Soluble Solid

Effect of Postharvest Treatments on Quality and Shelf Life of Mandarin (Citrus reticulata Blanco)

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American Journal of Plant Sciences 2016年第7期7卷 1098-1105页

作者： Pradeep Raj Rokaya Dilli Ram Baral Durga Mani gautam Arjun Kumar Shrestha krishna Prasad Paudyal Agriculture and Forestry University Rampur Chitwan Nepal National Agricultural Research Institute (NARI) NARC Khumaltar Lalitpur Nepal

Nepal produces large quantity of mandarin (Citrus reticulata Blanco) annually but faces big losses due to improper postharvest treatments. The experiment was carried out during 2012-2013 with the objective of assessing the effect of different postharvest treatments on quality and shelf life of mandarin. The postharvest treatments were: wax emulsion at 10%, bavistin at 0.1%, wax at 10% with bavistin at 0.1%, calcium chloride at 1%, Jeevatu at 5% along with untreated fruits as a control. The experiment was conducted for four weeks of storage at ambient condition in Nepal Agricultural Research Council, Khumaltar, Kathmandu. Wax in combination with bavistin was found as the most effective in reducing the physiological loss in weight, whereas bavistin proved to reduce decay loss up to four weeks of storage. The fruits treated with wax alone and with combination of bavistin retained maximum firmness, juice percentage, vitamin C and palatability rating during the storage. The minimum total soluble solid and maximum titrable acidity were recorded in the fruits treated with wax plus bavistin. The present findings indicate that mandarin can be stored up to four weeks when treated with wax as well as wax with bavistin in the condition with 14°C - 18°C temperature and 45% - 73% relative humidity.

关键词： Mandarin Fruit Quality Postharvest Treatments Palatability Rating and Postharvest Loss in Weight

Effect of Pre-Harvest Application of Gibberellic Acid on Fruit Quality and Shelf Life of Mandarin (Citrus reticulata Blanco)

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American Journal of Plant Sciences 2016年第7期7卷 1033-1039页

Mandarin (Citrus reticulata Blanco) is a promising fruit crop gaining popularity for its human nutrition and economic importance in Nepal. The qualitative losses during pre-harvest stage hinder the productivity and subsequently shorten the on-tree storability. An experiment was conducted to assess the effect of gibberellic acid on quality and shelf life of the mandarin fruit. GA3 at 10, 20, and 30 ppm as against of control were evaluated. Observations on fruit weight (g), fruit firmness (kg/cm2), rind colour (1 - 5 index), juice recovery (%), TSS/acid ratio, PLW (%), decay loss (%), and ascorbic acid (mg/100 ml) were recorded at three harvesting dates i.e. 20 Nov, 5 Dec, and 20 Dec and storage condition. It has been revealed that the fruits treated with GA3 at 20 ppm retained higher fruit weight (128.6 g), more firmness (3.54 kg/cm2), better juice recovery (57.75%), and greater TSS/acid ratio (21.24) at the end of study (20 December). The PLW was found less with GA3 at 30 ppm in both ambient (5.17%) and cellar (6.69%) condition as against untreated fruits (9.52% and 11.76%). Similarly, the decay loss was minimum in the fruits treated with GA3 at 30 ppm both with ambient (1.02%) and cellar condition (8.21%) as against control with ambient (5.54%) and cellar (21.58%).

关键词： Fruit Quality Gibberellic Acid Peel Puncture Resistance Physiological Loss in Weight Postharvest Shelf Life

Evolving provenance in the Proterozoic Pranhita-Godavari Basin,India

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Geoscience Frontiers 2015年第3期6卷 453-463页

作者： Udeni Amarasinghe Asru Chaudhuri Alan S.Collins gautam Deb Sarbani Patranabis-Deb Centre for Tectonics Resources and Exploration(TRaX)School of Earth and Environmental SciencesThe University of Adelaide Department of Geology Presidency College Geological Studies Unit(GSU) Indian Statistical Institute

The Pranhita-Godavari Basin in central eastern India is one of the Proterozoic ＂Purana＂ basins of cratonic India. New geochronology demonstrates that it has a vast depositional history of repeated basin reactivation from the Palaeoproterozoic to the Mesozoic. U-Pb laser ablation inductively coupled plasma mass spectrometry dating of detrital zircons from two samples of the Somanpalli Group--a member of the oldest sedimentary cycle in the valley--constrains its depositional age to - 1620 Ma and demonstrates a tripartite age provenance with peaks at - 3500 Ma, - 2480 Ma and - 1620 Ma, with minor age peaks in the Eoarchaean （ - 3.8 Ga） and at - 2750 Ma. These ages are consistent with palaeocurrent data suggesting a southerly source from the krishna Province and Enderby Land in East Antarctica. The similarity in the maximum depositional age with previously published autbigenic glauconite ages suggest that the origin of the Pranhita-Godvari Graben originated as a rift that formed at a high angle to the coeval evolving late Meosproterozoic krishna Province as Enderby Land collided with the Dharwar craton of India. In contrast, detrital zircons from the Cycle III Sullavai Group red sandstones yielded a maximum depositional age of 970 - 20 Ma and had age peaks of -2550 Ma, -1600 Ma and then a number of Mesoproterozoic detrital zircons terminating in three analyses at - 970 Ma. The provenance of these is again consistent with a southerly source from the Eastern Ghats Orogen and Antarctica. Later cycles of deposition include the overlying Albaka/Usur Formations and finally the late Palaeozoic to Mesozoic Gondwana Supergroup.

关键词： LA-icpms U-Pb zircon geochronology Godavari Purana Gondwana

Genetic Behaviour of Bacterial Wilt Resistance in Brinjal (Solanum melongena L.) in Tropics of Andaman and Nicobar Islands of India

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American Journal of Plant Sciences 2016年第2期7卷 333-338页

作者： Naresh Kumar Bainsla Shrawan Singh Pankaj Kumar Singh krishna Kumar Awanindra Kumar Singh Raj Kumar gautam Central Island Agricultural Research Institute Port Blair India Current Address: Division of Genetics Indian Agricultural Research Institute New Delhi India

Brinjal or eggplant (Solanum melongena L.) is severely affected by bacterial wilt caused by Ralstonia solanecearum in Andaman and Nicobar Islands. Resistant varieties are most suitable option to reduce crop losses from bacterial wilt but knowledge of resistance mechanism and its inheritance is important to develop resistant varieties. Further, majority of germplasm from mainland India showed susceptible reaction under Andaman conditions. Thus, the present study was done during 2010-2012 to understand the genetic behaviour of bacterial wilt resistance in brinjal “CARI-B-1” (R) × “Pusa Purple Long” (S) in hot humid tropical climate of Andaman Islands. For this, the population from single F1 fruit was advanced to F2 and F3 and recorded the reaction of segregating population in the sick plots. The results revealed that there is preponderance of recessive gene family wherein more than one gene acts in additive mode. Another cross between S. torvum (R) × Diglipur local collection (S) also showed the recessive gene action for resistance as observed in F2 generation. Besides, the study also advocated that mechanisms of resistance, escape with early resistance and progressive escape have been found to be operating in individuals of segregating population.

关键词： Egg Plant Ralstonia solanecearum Genetics Islands Resistance

Behaviour of Earth Dam under Seismic Load Considering Nonlinearity of the Soil

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Open Journal of Civil Engineering 2016年第2期6卷 75-83页

作者： Mohammad Asif Raja Bal krishna Maheshwari Galgotias University Gautam Budh Nagar India Indian Institute of Technology Roorkee India

The stability and safety are very important issues for the dam structure which are built in seismic regions. The dam body consists of soil materials that behave nonlinearly modelled with finite elements. The numerical investigation employs a fully nonlinear finite element analysis considering linear and elastic-plastic constitutive model to describe the material properties of the soil. In this paper, seismic analysis of an earthen dam is carried out using Geo-Studio software based on finite element method. Initially, the in-situ stress state analysis has been done before the earthquake established, and then its results are used in the seismic analysis as a parent analysis. A complete parametric study is carried out to identify the effects of input motion characteristics, soil behaviour and strength of the shell and core materials on the dynamic response of earthen dams. The real earthquake record is used as input motions. The analysis gives the overall pattern of the dam behaviour in terms of contours of displacements and stresses.

关键词： Earthen Dam Nonlinearity Seismic Response Earthquake Loads Elastic-Plastic Model