Factors influencing tree biomass and carbon stock in the Western Himalayas, India

Frontiers in Forests and Global Change, Год журнала: 2024, Номер 6

Опубликована: Янв. 9, 2024

The assessment of tree biomass and its carbon (C) stock at the local regional level is considered a crucial criterion for understanding impact changing environments on global cycle. In this context, we selected three sites in western Himalayas, covering parts Himachal Pradesh north-eastern Haryana. Each study site experiences distinct climatic conditions, vegetation types, elevations. We seek to elucidate determinants across different forest types Western Himalayas. found that temperate forests contributed most stock, with Cedrus deodara attaining highest values 782.6 ± 107.9 Mg/ha 360 49.7 Mg C/ha. contrast, Quercus leucotrichophora mixed had lowest 286.6 57.2 128.9 25.7 Mg/C ha, respectively. Only few species, such as Abies pindrow , floribunda semecarpifolia accounted significant stock. lower elevation subtropical species richness (8–12 species) stem density (558.3 62.9 866.6 57.7 trees/ha). Furthermore, diameter, total basal cover, height emerged strongest predictors C remaining variables showed no associations, including diversity, attributes elevation. Thus, our extended assertion composition structural attributes, apart from topographic factors, are equally important determining ecosystems. Our indicated Himalayas possess storage climate change mitigation potential.

Язык: Английский

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Stable reverse J-shaped diameter distribution occurs in an old-growth karst forest

Journal of Forestry Research, Год журнала: 2024, Номер 35(1)

Опубликована: Июль 2, 2024

Язык: Английский

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Fitting and Evaluating Taper Functions to Predict Upper Stem Diameter of Planted Teak (Tectona grandis L.f.) in Eastern and Central Regions of Nepal

Forests, Год журнала: 2025, Номер 16(1), С. 77 - 77

Опубликована: Янв. 5, 2025

Teak [Tectona grandis L.f.] has a wide distribution range in tropical countries and is Nepal’s second most planted commercial tree species. This study aimed to develop robust reliable taper equation for species Nepal. To achieve this, 15 parametric equations were fitted evaluated using the diameter height data of 100 trees sampled from two stands Sagarnath Plantation projects, The set was split into training (90%) testing (10%) sets based on trees’ ID, model fitting conducted phases. In first phase, nonlinear models 10-fold cross-validation, performance fit validation statistics. top five further analyzed phase mixed effects framework account variance correlation structures. modified Bi performed best under fixed modeling (R2 = 0.96, RMSE 1.83 cm). However, Sharma Zhang mixed-effects 0.97, 1.54 Therefore, we suggest variable exponent as Teak. Zhang’s recommended its high accuracy better over previously exponents equations.

Язык: Английский

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Simultaneous density-integral system for estimating stem profile, volume, wood density, and biomass of fourteen tree species in northeast China

Computers and Electronics in Agriculture, Год журнала: 2025, Номер 236, С. 110453 - 110453

Опубликована: Апрель 28, 2025

Язык: Английский

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Model of stem taper of Scots pine (Pinus sylvestris) in the Kostroma region

Forestry Engineering Journal, Год журнала: 2024, Номер 13(4), С. 5 - 22

Опубликована: Фев. 12, 2024

Models of the stem taper have become widespread in forestry research. based on equations are capable determining with sufficient accuracy assortment potential forest stands. For Kostroma region, no work has previously been carried out aimed at modeling trunks. Therefore, goal study was to search and justify models a tree trunk one equation that most correctly describe change diameter height Scots pine stands growing region. As experimental data, 10064 measurements 692 trees were obtained. To carry analysis, 19 selected. Calculations Python environment. The calculated values quality metrics, graphical analysis residuals errors made it possible establish four-parameter model adequately describes predicted using any makes analyze structure without resorting felling. Further research is required developing standards for trunks proposed model.

Язык: Английский

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Taper functions to predict the upper stem diameter of Chir pine (Pinus roxburghii) in the mid-hills of Nepal

Trees Forests and People, Год журнала: 2024, Номер 17, С. 100627 - 100627

Опубликована: Июль 14, 2024

A function that predicts the upper stem diameters of an individual tree is helpful in better quantifying volume and devising sustainable management commercially ecologically important species. This study compares three forms taper equation (single, variable-exponent, segmented) using destructive sample data collected from 80 Chir pine (Pinus roxburghii Sarg.) trees across adjacent stands Mid hills Nepal. mixed-effects modeling approach was used to evaluate 13 different functions, selecting best parameter association with random effect avoid overparameterization. Additionally, these models were fitted minimize errors by correlation structure continuous autoregressive order 1 (corCAR1) variance a power function. All statistically significant at 5% level likelihood ratio test when compared without error minimization. Furthermore, model performance (root mean square error, absolute pseudo-R2) evaluated k-fold cross-validation procedure. Although all functions described more than 95% variation diameter prediction, single-form Bennett Swindel (1972) Amidon (1984), variable-exponent form Sharma Zhang (2004), segmented Max Burkhart (1976) explained 98% percent variability. Residual diagnostics indicated Zhang's (2004) provided constant minimum predicting along 8 20 m length, whereas other exhibited higher residual errors. Despite model's performance, variability prediction would affect its applicability estimating any merchantable height trees.

Язык: Английский

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Allometric tree volume models for Pinus roxberghii and Cedrus deodara in Karnali Province, Nepal

Forest Ecology and Management, Год журнала: 2023, Номер 546, С. 121364 - 121364

Опубликована: Авг. 25, 2023

Язык: Английский

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Mathematical system based on taper functions for distribution by structural product of culms in three giant bamboo taxa

Forest Systems, Год журнала: 2023, Номер 32(2), С. e010 - e010

Опубликована: Июнь 12, 2023

Aim of study: To generate a mathematical system to distribute structural products bamboo culms. Study area: Northeastern region the state Puebla, Mexico. Materials and methods: Eighty-seven culms Bambusa oldhamii Munro, Guadua aculeata Rupr. angustifolia Kunth were collected in Four taper functions evaluated, one with best predictive capacity was fitted model diameter over under wall together thickness model. The fitting strategy consisted additive equations using Weighted-Nonlinear Seemingly Unrelated Regression (WNSUR) procedure autocorrelation correction, combination Dummy Variable technique. Main results: Fang & Bailey case 1-a selected describe wall; Cao Papper used thickness. R2adj 0.977, 0.944 0.918, RMSE values 0.186 cm, 0.200 cm 0.134 for wall, thickness, respectively. G. had greatest followed by aculeata. highest proportion primary product presented angustifolia. generated parameters specific each taxon. Research highlights: profile can be modeled functions. A distribution type developed consisting of: (1) and, (2) function estimate commercial height.

Язык: Английский

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Modeling tree stem volume for hill Shorea robusta Gaertn. forests in Karnali Province, Nepal

Trees Forests and People, Год журнала: 2024, Номер 18, С. 100675 - 100675

Опубликована: Сен. 4, 2024

Язык: Английский

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