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Development and evaluation of robust tree biomass equations for rubber tree (Hevea brasiliensis) plantations in India

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Forest Ecosystems 2017年第3期4卷 241-250页

作者： Biplab Brahma Gudeta W.Sileshi Arun Jyoti Nath Ashesh kumar Das Department of Ecology and Environmental Science Assam University

Background： In India, rubber（Hevea brasiliensis） plantations cover -0.8 million ha of land, emphasizing its significant role in the Earth＇s carbon dynamics. Therefore, it is important to estimate the biomass stocks of plantations precisely in the context of carbon management. Previous studies in India have focused on development of allometric equations for estimating aboveground biomass（AGB） through harvesting younger trees（up to 14 yr）only or on studies with small sample sizes without assessing model bias. The objective of this study was to develop biomass estimation models for different tree components in rubber plantations and assess model predictive performance at the stand ***： A total of 67 trees were harvested from plantations of different ages（6, 15, 27 and 34 yr） in North East India and their diameter at 200 cm（D）, height and dry weights of different tree components were recorded. The data were used for evaluation of H-D and biomass estimation models at the stand ***： The Michaelis-Menten function was found to be the most appropriate model for estimating tree height among 10 commonly used H-D models. For estimation of AGB and coarse root biomass, a model that involves tree volume（i.e. D2 H） was found to provide better prediction than either D or H alone or a model that combines H, D and stand density. The estimated AGB varied from 28 Mg·ha-（-1） in 6 yr. old plantation to 169 Mg·ha-（-1） in 34 yr. old *** coarse root biomass was estimated at 4 Mg·ha-（-1） for 6 yr. old plantation and 12 Mg·ha-（-1） for 34 yr. old ***： It is concluded that models involving tree volume are more appropriate for regional level biomass estimation than simple power-law models for individual stands. We recommend that the power-law model should not be used for estimation of AGB in plantations at different growth stages because power-law parameters can be biased due to data truncation.

关键词： Aboveground biomass Data truncation Michaelis-Menten function Power-law

Temporal Variations in Carbon Stock of Pinus roxburghii Sargent Forests of Himachal Pradesh,India

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Journal of Mountain Science 2014年第4期11卷 959-966页

作者： Shipra ShaH Dharam Prakash ShaRMA Nazir A.PALA Priyanka TRIPATHI Munesh kumar Department of Silviculture & Agroforestry College of Forestry Dr YS Parmar University of Horticulture & Forestry Nauni Solan 173230 India Departments of Forestry Faculty of Horticulture UBKV Pundibari Cooch Behar 736165 India Department of Forestry and Natural Resources H.N.B. Garhwal University Srinagar-Garhwal Uttarakhand 249161 India

The present study was conducted in Solan Forest Division of Himachal Pradesh covering an area of about 57,158 ha. The aim was to estimate and assess the temporal change in carbon stock of the Chil Working Circle, in two forest ranges of the Division, Solan and Dharampur, over the period of 1956-2011. The inventory data of the working plans of Solan Forest Division from 1956-1957, 1984-1985 and 2002-2003 were used in the present study while field data for biomass estimation was collected for the year *** results showed a declining trend in carbon stock over 1956-1984 period, however, an increasing trend over 1984-2002 was observed, which showed a further increase for the period 2002-2011. These fluctuating trends in the forest carbon stock can be related to increasing anthropogenic pressure on forests and the subsequent introduction of a ban on green felling envisaging efficient forest management, both of which affect the forest carbon pool significantly.

关键词： Carbon stock Temporal change Climatechange Forest inventory

Tree species composition and diversity in montane forests of Garhwal Himalaya in relation to environmental and soil properties

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Journal of Mountain Science 2020年第12期17卷 3097-3111页

作者： Dinesh Singh RAWAT P.TIWARI Sudipta kumar DAS J.K.TIWARI Department of Botany&Microbiology HNB Garhwal UniversitySrinagar(Garhwal)-246174UttarakhandIndia Central National Herbarium Botanical Survey of IndiaHowrah-711103West BengalIndia

The montane forests of Garhwal Himalaya were investigated for tree species composition and diversity in relation to environmental and edaphic variables.A stratified random sampling approach was adopted to collect the field data from each forest.A total of 39 tree species belonging to 31 genera and 23 families were recorded from the sampling area(6 forest stands ×10 plots in each).Lauraceae with 5 species was the largest family while Quercus(4 species) emerged as the largest ***-area curve(asymptote) predicted more species than the observed number of *** analysis has shown that the two Abies pindrow dominant forest stands had the highest similarity in tree species *** tree stem density ranged from 540-1170 ha-1,basal area 23.01-55.94 m^2 ha-1,ShannonWiener diversity index 1.69-2.49,evenness index0.42-0.74,beta diversity 0.40-0.82 and similarity index 0.17-0.54 in the six studied ***-way indicator species analysis(TWINSPAN) identified four distinct tree communities in the study area with Daphniphyllum himalayense,Abies pindrow,Quercus oblongata,and Pinus roxburghii as indicator species of corresponding *** correspondence analysis(CCA) ascertained the TWINSPAN results and revealed the relation of tree species with environmental and edaphic *** phytosociological attributes of tree species varied from one forest stand to another;however,the tree species richness,density,and diversity peaked at intermediate elevation on the north *** reveal that tree composition and diversity in the montane forests of Garhwal Himalaya are influenced by both environmental(elevation and slope aspect)and soil variables(texture,water holding capacity,moisture content,available N,exchangeable P,and pH).This study will help in understanding the forest distribution across the western Himalaya,guiding the conservationists and policymakers in carrying out conservation-related management activities,designing the long-

关键词： Diversity Tree species Montane forests Soil properties Western Himalaya

Estimation of carbon pools in secondary tropical deciduous forests of Odisha,India

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Journal of Forestry Research 2021年第2期32卷 663-673页

作者： Subhashree Pattnayak M.kumar N.K.Dhal Sudam C.Sahu Department of Life Sciences Sambalpur UniversitySambalpurOdisha 768019India Environment and Sustainability Department CSIR-IMMTBhubaneswarOdisha 751013India Department of Botany North Orissa UniversityBaripadaOdisha 757003India

Secondary tropical forests sequester atmospheric CO 2 at relatively faster rates in vegetation and in soil than old-growth primary *** understanding of biomass and carbon stocks in different plant functional types of these forests is ***,diversity,composition,soil features and carbon stocks in six distinct plant functional types,namely:Moist Mixed-Deciduous Forest,Peninsular Sal Forest(PSF),Semi-Evergreen Forest(SEF),Planted Teak Forest,Bamboo Brakes(BB),and Degraded Thorny Shrubby Forest were quantified as secondary tropical deciduous forests of the Chandaka Wildlife Sanctuary,Eastern Ghats of Odisha,***-one species≥10 cm Girth at breast height(GBH)were recorded,belonging to 38 families and 65 ***-ground biomass carbon and soil organic carbon ranged from 2.1–72.7 Mg C ha^(−1) and 20.6–67.1 Mg C ha^(−1),respectively,among all plant functional *** organic carbon and important value index were positively correlated with above-ground biomass *** carbon allocation was in SOC pool(51–91%),followed by the above-ground biomass pool(9–52%),indicating SOC is one of the major carbon sinks in secondary dry *** results highlight the importance of secondary tropical deciduous forests in biodiversity conservation and ecological importance in reducing greenhouse gases.

关键词： Chandaka wildlife Sanctuary Diversity indices Soil organic carbon Above-ground biomass carbon Correlation study

Enhanced Long Short Term Memory for Early Alzheimer's Disease Prediction

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Intelligent Automation & Soft Computing 2023年第2期35卷 1277-1293页

作者： M.Vinoth kumar M.Prakash M.Naresh kumar H.Abdul Shabeer Department of Information Science and Engineering Dayananda Sagar Academy of Technology&ManagementKanakapura Main Road560082BangaloreIndia Department of Data Science and Business Systems School of Computing SRM Institute of Science and TechnologyKattankulathurChengalpattu603203TamilnaduIndia Department of ECE Vardhaman College of EngineeringHyderabad501218India IBM India Pvt Ltd. DLF IT ParkChennai600125India

The most noteworthy neurodegenerative disorder nationwide is appar-ently the Alzheimer's disease(AD)which ha no proven viable treatment till date and despite the clinical trials showing the potential of preclinical therapy,a sen-sitive method for evaluating the AD has to be developed *** to the correla-tions between ocular and brain tissue,the eye(retinal blood vessels)has been investigated for predicting the ***,en enhanced method named Enhanced Long Short Term Memory(E-LSTM)has been proposed in this work which aims atﬁnding the severity of AD from ocular ***ﬁnd the level of disease severity,the new layer named precise layer was introduced in E-LSTM which will help the doctors to provide the apt treatments for the patients *** avoid the problem of overﬁtting,a dropout has been added to *** the existing work,boundary detection of retinal layers was found to be inaccurate during the seg-mentation process of Optical Coherence Tomography(OCT)image and to over-come this issue;Particle Swarm Optimization(PSO)has been *** the best of our understanding,this is theﬁrst paper to use Particle Swarm *** compared with the existing works,the proposed work is found to be per-forming better in terms of F1 Score,Precision,Recall,training loss,and segmen-tation accuracy and it is found that the prediction accuracy was increased to 10%higher than the existing systems.

关键词： Alzheimer's disease enhanced LSTM particle swarm optimization OCT image boundary detection

Zinc partitioning in basmati rice varieties as influenced by Zn fertilization

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The Crop Journal 2018年第2期6卷 136-147页

作者： Prakash Chand Ghasal Yashbir Singh Shivay Vijay Pooniya Mukesh Choudhary Rakesh kumar Verma ICAR-Indian Agricultural Research Institute New Delhi 110012India

Zinc(Zn) ferti-fortification using different sources and methods in Zn deficient soils is being advocated to increase Zn concentration in rice kernel as an alternative to pursuing greater Zn-use efficiency(ZnUE). A two-year field study was conducted to assess the effect of Zn application on Zn content and uptake at several growth stages and in several parts of the rice kernel: hull, bran, and the white rice kernel. Variety ‘PB 1509' with 1.25 kg Zn ha^(-1) as Zn-EDTA + 0.5% foliar spray(FS) at maximum tillering(MT) and panicle initiation(PI) stages registered the highest Zn content in hull, bran, and white rice kernel. Among parts of the rice kernel, Zn concentration decreased in the order hull > bran > white rice kernel,indicating that brown rice kernels are much denser in Zn content than polished *** the higher Zn accumulation in the bran, brown rice consumption, especially in Asia and Africa, could be recommended to overcome Zn malnutrition. The variety ‘PB 1401'showed the highest Zn uptake in rice straw, while ‘PB 1509' showed the highest Zn uptake in hull and white rice kernel. Application of 1.25 kg Zn ha^(-1)(Zn-EDTA) + 0.5% FS at MT and PI and 2.5 kg Zn ha^(-1) ZnSO_4·7H_2O(ZnSHH) + 0.5% FS at MT and PI resulted in higher Zn uptake than other treatments. On average, about one third of total Zn uptake remained in the white rice kernel, with the remaining two thirds accumulating in both hull and bran of brown rice. Zn-EDTA along with 0.5% FS, despite the application of a lower quantity of Zn leading to the highest Zn mobilization efficiency index(ZnMEI) and Zn-induced nitrogen recovery efficiency(ZniNRE), produced the highest kernel yield. However, of the two Zn sources, Zn-EDTA contributed more to the increase in ZnUE than did ZnSHH.

关键词： Aromatic rice Zn fertilization Zn-EDTA ZnSO4·7H2O Zn use efficiency Zn mobilization efficiency index

Co-inoculation of indigenous Pseudomonas oryzihabitans and Bradyrhizobium *** the growth,symbiotic efficacy,nutrient acquisition,and grain yield of soybean

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Pedosphere 2022年第3期32卷 438-451页

作者： Kailash Chand KUMAWAT Inderjeet SINGH Sharon NAGPAL Poonam ShaRMA Rajeev kumar GUPTA Asmita SIRARI Department of Microbiology Punjab Agricultural UniversityLudhiana 141004(India) Department of Plant Breeding and Genetics Punjab Agricultural UniversityLudhiana 141004(India) Department of Soil Science Punjab Agricultural UniversityLudhiana 141004(India)

Soil microbes play a vital role in improving plant growth,crop productivity,and soil health through solubilization of essential *** investigation was conducted to access the efficacy of Bradyrhizobium ***-3 and the indigenous phosphate-solubilizing Pseudomonas oryzihabitans LSE-3 in improving the symbiosis,nutrient accumulation,and yield of *** isolate LSE-3,selected on the basis of phosphate solubilization,was screened for beneficial traits,antagonistic activities,and *** levels of indole acetic acid production(50.34±2.35μg mL^(-1)),phosphate solubilization(184.4±7.4 mg L^(-1)),biofilm formation(optical density at 560 mm,1.3896±0.04),siderophore production(121.46±1.61μg mL^(-1)),and 1-aminocyclopropane-1-carboxylate deaminase activity(0.51±0.07 mmolα-ketobutyrateμg^(-1) protein h^(-1))were significantly higher with the dual inoculants(LSBR-3 and LSE-3)than with the single inoculant *** plant growth-promoting traits of single and dual inoculants were evaluated for the synergistic effects on soybean under field *** plots treated with LSBR-3+LSE-3 exhibited improvement in seed germination,plant height,plant biomass,and chlorophyll content compared with the uninoculated *** inoculant treatments resulted in significantly higher symbiotic efficacy evidenced by increased nodulation(40.0±0.75 plant^(-1)),nodule biomass(188.52±6.29 mg plant^(-1)),and leghemoglobin content(11.02±0.83 mg g^(-1) fresh nodule),and significantly increased activities of phosphatase(75.16±3.17 and 58.77±6.08μg p-nitrophenol g^(-1) h^(-1) for alkaline and acid phosphatase,respectively)and dehydrogenase(32.66±1.92μg triphenylformazan g^(-1) h^(-1))compared with the *** inoculation with LSBR-3 and LSE-3 enhanced the uptake of macro-and micronutrients,reduced Na content in shoots,and resulted in 10.85%higher grain yield and ***$96.80 ha^(-1) higher profit compared with the *** is the first report on the effectiv

关键词： bacteria biofilm formation phosphate solubilization plant growth-promoting trait sustainable agriculture zinc solubilization

Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

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Journal of Environmental Sciences 2013年第9期25卷 1847-1857页

作者： Ciaran Lewis Rashad Rafique Nelius Foley Paul Leahy Gerard Morgan John Albertson Sandeep kumar Gerard Kiely Department of Civil and Environmental Engineering University College Cork Department of Microbiology and Plant Biology University of Oklahoma Environmental Research Institute University College Cork Aquatic Services Unit Environmental Research Institute University College Cork Department of Civil and Environmental Engineering Duke University Department of Plant Science South Dakota State University

We carried out a one year （2002） study of phosphorus （P） loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months. The annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha, respectively. The annual total phosphorus （TP） export in stream-flow was 2.61, 2.48 and 1.61 kg P/ha for the 17, 211 and 1524 ha catchments, respectively, compared with a maximum permissible （by regulation） annual export of ca. 0.35 kg P/ha. The export rate （ratio of P export to P in land applications） was 9.6% and 6.6% from the 17 and 211 ha catchments, respectively. On average, 70% of stream flow and 85% of the P export occurred during the five wet months （October to February） indicating that when precipitation is much greater than evaporation, the hydrological conditions are most favourable for P export. However the soil quality and land use history may vary the results. Particulate P made up 22%, 43% and 37% of the TP export at the 17, 211 and 1524 ha catchment areas, respectively. As the chemical fertilizer was spread during the grass growth months （March to September）, it has less immediate impact on stream water quality than the slurry applications. We also show that as the catchment scale increases, the P concentrations and P export decrease, confirming dilution due to increasing rural catchment size. In the longer term, the excess P from fertilizer maintains high soil P levels, an antecedent condition favourable to P loss from soil to water. This study confirms the significant negative water quality impact of excess P applications, particularly liquid animal slurry applications in wet winter months. The findings suggest that restricted P application in w

关键词： phosphorus fertilizer slurry exports grassland land management water quality eutrophication

Assessment of biomass and net primary productivity of a dry tropical forest using geospatial technology

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Journal of Forestry Research 2019年第1期30卷 157-170页

作者： Tarun kumar Thakur S.L.Swamy Arvind Bijalwan Mammohan J.R.Dobriyal Department of Environmental Science Indira Gandhi National Tribal University (IGNTU) Department of Forestry Indira Gandhi Agricultural University Faculty of Technical Forestry Indian Institute of Forest Management Navsari Agriculture University

This study quantifies biomass, aboveground and belowground net productivity, along with additional environmental factors over a 2-3 year period in Barnawapara Sanctuary of Chhattisgarh, India through satellite remotesensing and GIS techniques. Ten sampling quadrates20×20, 5×5 and 1×1 m were randomly laid for overstorey (OS), understorey (US) and ground vegetation(GS), respectively. Girth of trees was measured at breast height and collar diameters of shrubs and herbs at 0.1 m height. Biomass was estimated using allometric regression equations and herb biomass by harvesting. Net primary productivity (NPP) was determined by Ssumming biomass increment and litter crop values. Aspect and slope influenced the vegetation types, biomass and NPP in different forests. Standing biomass and NPP varied from 18.6 to101.5 Mg ha^(-1) and 5.3 to 12.7 Mg ha^(-1) a^(-1), respectively,in different forest types. The highest biomass was found in dense mixed forest, while net production recoded in Teak forests. Both were lowest in degraded mixed forests of different forest types. OS, US and GS contributed 90.4, 8.7and 0.7%, respectively, for the total mean standing biomass in different forests. This study developed spectral models for the estimation of biomass and NPP using Normalized Difference Vegetation Index and other vegetation *** study demonstrated the potential of geospatial tools for estimation of biomass and net productivity of dry tropical forest ecosystem.

关键词： Allometric regression equations Fine root biomass Litter fall LAI NDVI Spectral models