Models for Predicting Tree Diameter at Breast Height from Over and Under Bark Diameter of Stump in Eucalyptus camaldulensis Plantations

Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 20, 2025

Allometric functions that predict tree diameter at breast height (D) from stump (DS), referred to as DS-D models, are essential for estimating forest metrics like stand volume and belowground carbon (C), especially when D cannot be measured, such after inadequately recorded clearcutting or illegal logging of threatened species.Many available models generic diverse species ecological condition, arelargely based on DS measured over bark (DSoB). Studies show thickness (BT), a factor DSoB, varies intra-species across ecosystemsas response fire history other factors. This raises concerns about the reliance generic, DSoB-based modelsfor inventoryon regenerating clearcut plantation sites. We hypothesize local calibrated with under (DSuB) better account in-situecological variability inBT. To test this, we gathered data through destructive non-destructive sampling clonally propagated (CP), post-fire recovery (FR), coppice-regenerated (CR) stands monoculture Eucalyptus camaldulensisplantations (ECPs) in East Africa. Using data, employed machine learning traditional statistical methods calibrate alternately DSoB DSuB predictor variables. Through error residuals effect sizes analyses, compared (1) performance previously published, ex-situgeneric equations versus study-derived (2) effectivenessDSoB DSoBboth input variables (3) assessed variation between non-fire impacted ECP stands. The results showed in-situ outperformed ex-situ substituting regressors improved model accuracy, substitution variable did not reduce models. (4) modeling allometry was complicated by high heterogeneity classes. These findings recalibrating can capture due circumvention environmental effects BT. further confirm utility even stump's layer is missing.

Language: Английский

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Synergistic mapping of urban tree canopy height using ICESat-2 data and GF-2 imagery

International Journal of Applied Earth Observation and Geoinformation, Journal Year: 2025, Volume and Issue: 136, P. 104348 - 104348

Published: Jan. 31, 2025

Language: Английский

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A Novel Method for Extracting DBH and Crown Base Height in Forests Using Small Motion Clips

Forests, Journal Year: 2024, Volume and Issue: 15(9), P. 1635 - 1635

Published: Sept. 16, 2024

The diameter at breast height (DBH) and crown base (CBH) are important indicators in forest surveys. To enhance the accuracy convenience of DBH CBH extraction for standing trees, a method based on understory small motion clips (a series images captured with slight viewpoint changes) has been proposed. Histogram equalization quadtree uniformization algorithms employed to extract image features, improving consistency feature extraction. Additionally, depth map construction point cloud reconstruction is improved by minimizing variance cost function. Six 20 m × square sample plots were selected verify effectiveness method. Depth maps clouds reconstructed from clips, trees extracted using pinhole imaging model. results indicated that root mean error (RMSE) ranged 0.60 cm 1.18 cm, relative errors ranging 1.81% 5.42%. Similarly, RMSE 0.08 0.21 m, 1.97% 5.58%. These meet standards required proposed enhances efficiency extracting tree structural parameters close-range photogrammetry (CRP) forestry. A rapid accurate provided this method, laying foundation subsequent resource management monitoring.

Language: Английский

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Exploration of morphological diversity to select naturally occurring promising walnut (Juglans regia L.) genotypes from the North-Western Himalayan region

South African Journal of Botany, Journal Year: 2024, Volume and Issue: 177, P. 264 - 278

Published: Dec. 13, 2024

Language: Английский

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