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Modelling tree volume for a tropical rainforest in Okomu National Park, Edo State, Nigeria
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作者 H.I.Aigbe D.H.Japheth U.E.Ekwugha 《Journal of Forestry Research》 2025年第4期189-203,共15页
Volume models for the long-term management of Okomu National Park in Nigeria are not available. The main challenge in assessing forest resources is the lack of accurate, species-specific baseline data and updated info... Volume models for the long-term management of Okomu National Park in Nigeria are not available. The main challenge in assessing forest resources is the lack of accurate, species-specific baseline data and updated information on volume models, growth rates, and disturbances. This complicates the development of effective management plans. This study addresses this by modelling tree volume using temporary sample plots laid out using a systematic line transect method Data was collected from 16 40 m × 50 m plots using a Spiegel relascope. DBH, top, middle, and base diameters, and overall height were measured for trees ≤ 10 cm DBH. Newton’s formula calculated volume of each tree, and per hectare estimates generated. The results showed an average of 132 trees per hectare. Population densities of individual species ranged from 1–11/ha, indicating a low density. Strombosia pustulata was the most abundant species. For coefficients that form the basis for species grouping, species-specific volume equations were developed and grouped into three clusters. Regression equations were fitted and selected based on specific statistical metrics. The volume models showed that generalized (V_(i)=b_(0)+b_(1)(D_(i)^(2)H_(i))+ε_(i)) functions, based on the statistical metrics, performed more effectively. The generalized functions exhibited superior performance, evidenced by the uniform residual plot distribution for DBH^(2)H, implying consistent experimental error and adherence to regression assumptions. A t-test at 95% confidence showed that the discrepancy between predicted and actual values was insignificant. This study indicates that the prediction models provide effective management tools for climate mitigation and determining carbon sequestration by a tropical forest. 展开更多
关键词 MODELLING volume equations Tropical rainforest Okomu National Park tree species
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Construction of tree volume equations for Chinese fir plantations in Guizhou Province, southwestern China 被引量:5
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作者 Zhong-Sheng XIA Wei-Sheng ZENG +1 位作者 Song ZHU Hong-Zhang LUO 《Forestry Studies in China》 CAS 2013年第3期179-185,共7页
Forest volume, the major component of forest biomass, is an important issue in forest resource monitoring.It is estimated from tree volume tables or equations. Based on tree volume data of 1840 sample trees from Chine... Forest volume, the major component of forest biomass, is an important issue in forest resource monitoring.It is estimated from tree volume tables or equations. Based on tree volume data of 1840 sample trees from Chinese fir (Cunninghamia lanceolata) plantations in Guizhou Province in southwestern China, parallel one- and two-variable tree volume tables and tree height curves for central and other areas were constructed using an error-in-variable modeling method. The results show that, although the one-variable tree volume equations and height curves between the central and other areas were significantly different, the two-variable volume equations were sufficiently close, so that a generalized two-variable tree volume equation could be established for the entire province. 展开更多
关键词 tree volume two-variable equation one-variable equation error-in-variable modeling method parallel models Chinese fir
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Combined Fault Tree Analysis and Bayesian Network for Reliability Assessment of Marine Internal Combustion Engine
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作者 Ivana Jovanović Çağlar Karatuğ +1 位作者 Maja Perčić Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期239-258,共20页
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ... This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels. 展开更多
关键词 Fault tree analysis Bayesian network RELIABILITY REDUNDANCY Internal combustion engine
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Formulae of Tree Height Curve and Volume Curve Derived from Theory of Column Buckling
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作者 郑小贤 刘东兰 +1 位作者 刘玉洪 宋新民 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第2期91-93,共3页
In this paper, the new formulae of tree height curve and volume cdrie were derived from the theory of column buckling. They were applied to artificial Pine (Pinus sylvestris var. mongolica) and Larch (Larix principis ... In this paper, the new formulae of tree height curve and volume cdrie were derived from the theory of column buckling. They were applied to artificial Pine (Pinus sylvestris var. mongolica) and Larch (Larix principis rupprechtii). The results demonsed that the new formulae wee more effeCtive and precise than conventional formulae of height curve and volume curve. 展开更多
关键词 COLUMN BUCKLING theory tree HEIGHT CURVE volume CURVE
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The distribution and frequency of damage to roadside trees in low-volume road construction
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作者 Majid Lotfalian Mehran Nasiri 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第1期221-226,共6页
We investigated the distribution and frequency of damage to tree stands adjacent to low-volume roads according to the type of hillside materials involved(soil or rock) and hillside gradient in mountainous forests of... We investigated the distribution and frequency of damage to tree stands adjacent to low-volume roads according to the type of hillside materials involved(soil or rock) and hillside gradient in mountainous forests of northern Iran. A total of 80 plots were systematically and randomly sampled to record damaged trees(bending,crushing and wounding) by class of hillside gradient and materials at the edge of road. Tree wounding and crushing at rock slopes was significantly greater than at hillsides with a mix of clay soil(p / 0.05). Damage on hillsides with slope gradients[45% were 2, 8.5 and 2.3 times more frequent than on hillsides with slope gradient/15% for bending, crushing and wounding, respectively. The damage distribution varied according by type and the most frequent damage was tree wounding(p / 0.05). The damage distribution was measured at distances of 4, 5 and 8 m from the road fillslope for tree bending, crushing and wounding, respectively. Using hydraulic excavators and physical barriers(wooden obstruction and synthetic holder) during earthworks for road construction could reduce these damage. 展开更多
关键词 Low-volume road construction tree damage Hillside materials GRADIENT DISTRIBUTION
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Urban tree species classification based on multispectral airborne LiDAR 被引量:1
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作者 HU Pei-Lun CHEN Yu-Wei +3 位作者 Mohammad Imangholiloo Markus Holopainen WANG Yi-Cheng Juha Hyyppä 《红外与毫米波学报》 北大核心 2025年第2期211-216,共6页
Urban tree species provide various essential ecosystem services in cities,such as regulating urban temperatures,reducing noise,capturing carbon,and mitigating the urban heat island effect.The quality of these services... Urban tree species provide various essential ecosystem services in cities,such as regulating urban temperatures,reducing noise,capturing carbon,and mitigating the urban heat island effect.The quality of these services is influenced by species diversity,tree health,and the distribution and the composition of trees.Traditionally,data on urban trees has been collected through field surveys and manual interpretation of remote sensing images.In this study,we evaluated the effectiveness of multispectral airborne laser scanning(ALS)data in classifying 24 common urban roadside tree species in Espoo,Finland.Tree crown structure information,intensity features,and spectral data were used for classification.Eight different machine learning algorithms were tested,with the extra trees(ET)algorithm performing the best,achieving an overall accuracy of 71.7%using multispectral LiDAR data.This result highlights that integrating structural and spectral information within a single framework can improve the classification accuracy.Future research will focus on identifying the most important features for species classification and developing algorithms with greater efficiency and accuracy. 展开更多
关键词 multispectral airborne LiDAR machine learning tree species classification
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Establishment of an efficient Agrobacterium rhizogenes-mediated hairy root transformation method for subtropical fruit trees 被引量:1
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作者 Mao Yin Yonghua Jiang +4 位作者 Yingjie Wen Fachao Shi Hua Huang Qian Yan Hailun Liu 《Horticultural Plant Journal》 2025年第4期1699-1702,共4页
Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herb... Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herbaceous plants,with notable applications in species such as Arabidopsis(Yin et al.,2024),soybean(Zhang et al.,2024),rice(Zhang et al.,2020),and Chinese cabbage(Li et al.,2021).However,its application in fruit trees is limited.This is primarily due to their long growth cycles and lack of rapid,efficient,and stable transgenic systems,which severely hinders foundational research involving plant genetic transformation(Mei et al.,2024).Furthermore,for subtropical fruit trees,the presence of recalcitrant seeds adds an extra layer of difficulty to genetic transformation(Umarani et al.,2015),as most methods rely on seed germination as a basis for transformation. 展开更多
关键词 study gene function krenek plant genetic engineering hairy root transformation fruit trees agrobacterium rhizogenes subtropical fruit trees genetic transformation chinese cabbage li
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Possibilities of native endophytic fungi as entomopathogenic biocontrol agents at a local scale:the case of deciduous and non-deciduous Mediterranean forest trees 被引量:1
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作者 Álvaro Benito-Delgado Sergio Diez-Hermano Julio Javier Diez 《Journal of Forestry Research》 2025年第3期224-236,共13页
Tree endophytic fungi play an important role in reducing insect herbivory,either by repelling them or kill-ing them directly.Identifying which fungi show such activ-ity could lead to new environmentally friendly pesti... Tree endophytic fungi play an important role in reducing insect herbivory,either by repelling them or kill-ing them directly.Identifying which fungi show such activ-ity could lead to new environmentally friendly pesticides.In this study,the Mediterranean basin climate conditions are projected to harshen in the next decades,will increase vulnerability of tree species to pest invasions.Endophytic fungi were isolated from wood and leaves of Quercus pyr-enaica,Q.ilex and Q.suber and tested for virulence against adults of the mealworm beetle,Tenebrio molitor L.using a direct contact method.Only 3 of 111 sporulating isolates had entomopathogenic activity,all identified as Lecanicillium lecanii.The pathogenicity of L.lecanii on T.molitor resulted in a median lethal time(TL50)of 14-16 d.Compared with commercial products,L.lecanii caused faster insect death than the nematode Steinernema carpocapsae and nuclear polyhedrosis virus(no effect on T.molitor survival),and slower than Beauveria bassiana(TL50=5),Beauveria pseu-dobassiana(TL50=8d)and Bacillus thuriengensis(80%mortality first day after inoculation).Mortality was also accelerated under water stress,reducing TL50 by an addi-tional 33%.Remarkably,water stress alone had a comparable effect on mortality to that of L.lecanii isolates.This study confirms T.molitor as a good model insect for pathogenicity testing and agrees with management policies proposed in the EU Green Deal. 展开更多
关键词 BIOCONTROL PESTICIDE tree pest Native fungi Climate change
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Rapid springtime leaf osmotic adjustment,but low late-seasonal and interannual variation in leaf turgor loss points in three temperate tree species 被引量:1
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作者 Norbert Kunert 《Journal of Forestry Research》 2025年第4期31-40,共10页
Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interan... Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interannual differences in water availability are affecting π_(tlp) as a static trait.I monitored the seasonal variation of π_(tlp) during a drought year starting in early spring with juvenile leaves and assessed the interannual variation in π_(tlp) of fully matured leaves among years with diverting water availability for three temperate broad-leaved tree species.The largest seasonal changes in π_(tlp) occurred during leaf unfolding until leaves were fully developed and matured.After leaves matured,no significant changes occurred for the rest of the vegetation period.Interannual variation that could be related to water availability was only present in one of the three tree species.The results suggest that the investigated species have a rapid period of osmotic adjustment early in the growing season followed by a period of relative stability,when π_(tlp) can be considered as a static trait. 展开更多
关键词 Drought Leaf drought tolerance traits tree mortality Turgor loss point
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基于Extra Trees模型的咪唑类离子液体植物毒性预测及SHAP值分析
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作者 茹雨璇 曹雨希西 +2 位作者 胡肖肖 邵云海 马琳 《宝鸡文理学院学报(自然科学版)》 2025年第3期17-22,44,共7页
目的构建一种高效可行的机器学习模型用于咪唑类离子液体对植物的毒性预测,为绿色、低毒性离子液体的开发提供理论支持和新思路。方法收集200余个咪唑类离子液体对植物的毒性实验数据集,基于SMILES字符串提取分子描述符,构建了一个Extra... 目的构建一种高效可行的机器学习模型用于咪唑类离子液体对植物的毒性预测,为绿色、低毒性离子液体的开发提供理论支持和新思路。方法收集200余个咪唑类离子液体对植物的毒性实验数据集,基于SMILES字符串提取分子描述符,构建了一个Extra Trees预测模型。模型的性能通过决定系数(R^(2))、均方根误差(RMSE)等指标进行评估,并采用SHapley Additive exPlanations(SHAP)值分析预测结果,以量化特征值对毒性预测的贡献程度。结果Extra Trees模型在测试集上显示出良好的预测性能(R^(2)=0.944,RMSE=0.351)。SHAP分析揭示了分子中非极性基团、支链/环状结构、分子量等物理化学性质及分子结构对植物毒性的影响。结论构建的Extra Trees模型能够快速准确地预测咪唑离子液体的植物毒性,具有较好的泛化能力和鲁棒性,可为环境风险评估及绿色离子液体的设计开发提供科学依据。 展开更多
关键词 咪唑离子液体 机器学习 Extra trees模型 植物毒性
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Intelligent sequential multi-impulse collision avoidance method for non-cooperative spacecraft based on an improved search tree algorithm 被引量:1
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作者 Xuyang CAO Xin NING +4 位作者 Zheng WANG Suyi LIU Fei CHENG Wenlong LI Xiaobin LIAN 《Chinese Journal of Aeronautics》 2025年第4期378-393,共16页
The problem of collision avoidance for non-cooperative targets has received significant attention from researchers in recent years.Non-cooperative targets exhibit uncertain states and unpredictable behaviors,making co... The problem of collision avoidance for non-cooperative targets has received significant attention from researchers in recent years.Non-cooperative targets exhibit uncertain states and unpredictable behaviors,making collision avoidance significantly more challenging than that for space debris.Much existing research focuses on the continuous thrust model,whereas the impulsive maneuver model is more appropriate for long-duration and long-distance avoidance missions.Additionally,it is important to minimize the impact on the original mission while avoiding noncooperative targets.On the other hand,the existing avoidance algorithms are computationally complex and time-consuming especially with the limited computing capability of the on-board computer,posing challenges for practical engineering applications.To conquer these difficulties,this paper makes the following key contributions:(A)a turn-based(sequential decision-making)limited-area impulsive collision avoidance model considering the time delay of precision orbit determination is established for the first time;(B)a novel Selection Probability Learning Adaptive Search-depth Search Tree(SPL-ASST)algorithm is proposed for non-cooperative target avoidance,which improves the decision-making efficiency by introducing an adaptive-search-depth mechanism and a neural network into the traditional Monte Carlo Tree Search(MCTS).Numerical simulations confirm the effectiveness and efficiency of the proposed method. 展开更多
关键词 Non-cooperative target Collision avoidance Limited motion area Impulsive maneuver model Search tree algorithm Neural networks
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基于Adaboost和Decision Tree的地层岩性预测研究
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作者 杨春曦 肖文梁 +2 位作者 徐亚军 郝梓宇 鲍挺 《地下空间与工程学报》 北大核心 2025年第S2期634-642,650,共10页
本文旨在研究基于Adaboost和Decision Tree算法的地层岩性预测方法,通过对气井的地层岩性实测数据进行分析,筛选出深度、地层电阻率等九种关键地球物理参数,利用上述机器学习算法构建气井地层岩性预测模型。在模型构建过程中,为解决Adab... 本文旨在研究基于Adaboost和Decision Tree算法的地层岩性预测方法,通过对气井的地层岩性实测数据进行分析,筛选出深度、地层电阻率等九种关键地球物理参数,利用上述机器学习算法构建气井地层岩性预测模型。在模型构建过程中,为解决Adaboost SAMME和Decision Tree算法参数选取和优化难点,利用交叉验证法筛选出最优参数组合。结果表明:Adaboost SAMME算法在岩性和地层岩性预测方面表现优异,准确率高达96%以上,相对而言,Decision Tree算法准确率稍低,为87%;模型预测准确率随训练集比例的增大而增加,原始数据随机化处理可以提高模型预测准确率;主成分分析(PCA)效果明显优于奇异值分解(SVD)。研究成果可为地下空间与能源工程钻井的地层岩性预测提供参考。 展开更多
关键词 地层岩性预测 机器学习 ADABOOST Decision tree
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Unveiling urbanization effects on trees outside forests along the urban-rural gradient in megacity Bengaluru
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作者 Tao Jiang Maximilian Freudenberg +3 位作者 Christoph Kleinn V.P.Tewari B.N.Diwakara Nils Nolke 《Forest Ecosystems》 2025年第1期56-65,共10页
Rapid urbanization has caused significant changes along the urban-rural gradient,leading to a variety of landscapes that are mainly shaped by human activities.This dynamic interplay also influences the distribution an... Rapid urbanization has caused significant changes along the urban-rural gradient,leading to a variety of landscapes that are mainly shaped by human activities.This dynamic interplay also influences the distribution and characteristics of trees outside forests(TOF).Understanding the pattern of these trees will support informed decision-making in urban planning,in conservation strategies,and altogether in sustainable land management practices in the urban context.In this study,we employed a deep learning-based object detection model and high resolution satellite imagery to identify 1.3 million trees with bounding boxes within a 250 km^(2)research transect spanning the urban-rural gradient of Bengaluru,a megacity in Southern India.Additionally,we developed an allometric equation to estimate diameter at breast height(DBH)from the tree crown diameter(CD)derived from the detected bounding boxes.Our study focused on analyzing variations in tree density and tree size along this gradient.The findings revealed distinct patterns:the urban domain displayed larger tree crown diameters(mean:8.87 m)and DBH(mean:43.78 cm)but having relatively low tree density(32 trees per hectare).Furthermore,with increasing distance from the city center,tree density increased,while the mean tree crown diameter and mean tree basal area decreased,showing clear differences of tree density and size between the urban and rural domains in Bengaluru.This study offers an efficient methodology that helps generating instructive insights into the dynamics of TOF along the urban-rural gradient.This may inform urban planning and management strategies for enhancing green infrastructure and biodiversity conservation in rapidly urbanizing cities like Bengaluru. 展开更多
关键词 Individual tree detection URBANIZATION tree density tree crown diameter
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Iceberg Draft Prediction Using Several Tree-Based Machine Learning Models
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作者 AZIMI Hamed SHIRI Hodjat 《Journal of Ocean University of China》 2025年第5期1269-1288,共20页
The Arctic region is experiencing accelerated sea ice melt and increased iceberg detachment from glaciers due to climate change.These drifting icebergs present a risk and engineering challenge for subsea installations... The Arctic region is experiencing accelerated sea ice melt and increased iceberg detachment from glaciers due to climate change.These drifting icebergs present a risk and engineering challenge for subsea installations traversing shallow waters,where ice-berg keels may reach the seabed,potentially damaging subsea structures.Consequently,costly and time-intensive iceberg manage-ment operations,such as towing and rerouting,are undertaken to safeguard subsea and offshore infrastructure.This study,therefore,explores the application of extra tree regression(ETR)as a robust solution for estimating iceberg draft,particularly in the preliminary phases of decision-making for iceberg management projects.Nine ETR models were developed using parameters influencing iceberg draft.Subsequent analyses identified the most effective models and significant input variables.Uncertainty analysis revealed that the superior ETR model tended to overestimate iceberg drafts;however,it achieved the highest precision,correlation,and simplicity in estimation.Comparison with decision tree regression,random forest regression,and empirical methods confirmed the superior perfor-mance of ETR in predicting iceberg drafts. 展开更多
关键词 sea-bottom founded structures iceberg draft extra tree regression decision tree regression random forest regression
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Tree Detection in RGB Satellite Imagery Using YOLO-Based Deep Learning Models
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作者 Irfan Abbas Robertas Damaševičius 《Computers, Materials & Continua》 2025年第10期483-502,共20页
Forests are vital ecosystems that play a crucial role in sustaining life on Earth and supporting human well-being.Traditional forest mapping and monitoring methods are often costly and limited in scope,necessitating t... Forests are vital ecosystems that play a crucial role in sustaining life on Earth and supporting human well-being.Traditional forest mapping and monitoring methods are often costly and limited in scope,necessitating the adoption of advanced,automated approaches for improved forest conservation and management.This study explores the application of deep learning-based object detection techniques for individual tree detection in RGB satellite imagery.A dataset of 3157 images was collected and divided into training(2528),validation(495),and testing(134)sets.To enhance model robustness and generalization,data augmentation was applied to the training part of the dataset.Various YOLO-based models,including YOLOv8,YOLOv9,YOLOv10,YOLOv11,and YOLOv12,were evaluated using different hyperparameters and optimization techniques,such as stochastic gradient descent(SGD)and auto-optimization.These models were assessed in terms of detection accuracy and the number of detected trees.The highest-performing model,YOLOv12m,achieved a mean average precision(mAP@50)of 0.908,mAP@50:95 of 0.581,recall of 0.851,precision of 0.852,and an F1-score of 0.847.The results demonstrate that YOLO-based object detection offers a highly efficient,scalable,and accurate solution for individual tree detection in satellite imagery,facilitating improved forest inventory,monitoring,and ecosystem management.This study underscores the potential of AI-driven tree detection to enhance environmental sustainability and support data-driven decision-making in forestry. 展开更多
关键词 tree detection RGB satellite imagery forest monitoring precision forestry object detection remote sensing environmental surveillance forest inventory aerial imagery LIDAR AI in forestry tree segmentation
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Distributions of parvalbumin,calbindin-D28k,and calretinin in the cerebrum of Chinese tree shrews(Tupaia belangeri chinensis):A high-resolution neuroanatomical resource
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作者 Rong Zhang Jia-Li Long +4 位作者 Yi-Fan Ye Hao-Yun Ye Xiao-Nan Zhao Xing Cai Li Lu 《Zoological Research》 2025年第4期893-911,共19页
The Chinese tree shrew has gained prominence as a model organism due to its phylogenetic proximity to primates,offering distinct advantages over traditional rodent models in biomedical research.However,the neuroanatom... The Chinese tree shrew has gained prominence as a model organism due to its phylogenetic proximity to primates,offering distinct advantages over traditional rodent models in biomedical research.However,the neuroanatomy of this species remains insufficiently defined,limiting its utility in neurophysiological and neuropathological studies.In this study,immunofluorescence microscopy was employed to comprehensively map the distribution of three calciumbinding proteins,parvalbumin,calbindin D-28k,and calretinin,across the tree shrew cerebrum.Serial brain sections in sagittal,coronal,and horizontal planes from 12 individuals generated a dataset of 3638 cellular-resolution images.This dataset,accessible via Science Data Bank(https://doi.org/10.57760/sciencedb.23471),provides detailed region-and laminar-selective distributions of calcium-binding proteins valuable for the cyto-and chemoarchitectural characterization of the tree shrew cerebrum.This resource will not only advance our understanding of brain organization and facilitate basic and translational neuroscience research in tree shrews but also enhance comparative and evolutionary analyses across species. 展开更多
关键词 tree shrew Distribution PARVALBUMIN CALBINDIN CALRETININ RESOURCE
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Regulation of the main terpenoids biosynthesis and accumulation in fruit trees
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作者 Yujie Hu Tianyi Zheng +6 位作者 Jie Dong Wangze Li Xiaoyu Ma Jin Li Yulin Fang Keqin Chen Kekun Zhang 《Horticultural Plant Journal》 2025年第5期1761-1776,共16页
Terpenoids are vital secondary metabolites in plants that function as agents for defense and stress resistance.These genes not only play crucial roles in plant growth and development but also function in diverse biolo... Terpenoids are vital secondary metabolites in plants that function as agents for defense and stress resistance.These genes not only play crucial roles in plant growth and development but also function in diverse biological group interactions.Terpenoids released by fruit trees possess defensive properties and constitute a class of aromatic compounds.For some fruits,terpenoids are indispensable indicators for evaluating fruit quality and the economic value.Significant research progress has been made in terpenoids biosynthesis and regulation.In this review,we introduce the main terpenoids of fruit trees,emphasize synthetic enzymes and regulatory factors involved in the mevalonate pathway and the methylerythritol pathway,and analyze TPS gene family identification and diversity in several fruit tree species.Moreover,the regulation of terpenes biosynthesis,including the molecular interaction mechanisms of environmental factors and hormone signaling pathways,are comprehensively described.Our objective is to summarize the molecular regulatory network and research foundation of terpenoids biosynthesis,providing a reference for investigations of metabolic pathways and promoting the development of techniques for the regulation and breeding of terpenoids in fruit trees. 展开更多
关键词 TERPENOIDS Synthesis REGULATION Fruit trees secondary metabolite TPS
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Allometric equations quantify accelerated growth and carbon fixation in trees of northeastern north America
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作者 John Schwarzmann Donald M.Waller 《Forest Ecosystems》 2025年第5期919-932,共14页
A tree's basal area(BA)and wood volume scale exponentially with tree diameter in species-specifc patterns.Recent observed increases in tree growth suggest these allometric relationships are shifting in response to... A tree's basal area(BA)and wood volume scale exponentially with tree diameter in species-specifc patterns.Recent observed increases in tree growth suggest these allometric relationships are shifting in response to climate change,rising CO_(2) levels,and/or changes in forest management.We analyzed 9,214 cores from nine conifer and 11 broadleaf species grown in managed mixed-species stands in the upper Midwest to quantify how well diameter(diameter at breast height(DBH))serves to predict BA growth and above-ground wood and carbon(C).These samples include many large trees.We ft mixed models to predict BA growth and above-ground biomass/C from diameter,tree height,and the BA of nearby trees while controlling for site effects.Models account for 55%–83%of the variance in log(recent growth),improving predictions over earlier models.Growth-diameter scaling exponents covary with certain leaf and stem(but not wood)functional traits,reflecting growth strategies.LogBA increment scales linearly with log(diameter)as trees grow bigger in 16/20 species and growth actually accelerates in Quercus rubra L.Three other species plateau in growth.Growth only decelerates in red pine,Pinus resinosa Ait.Growth in whole-tree,above-ground biomass,and C accelerate even more strongly with diameter(mean exponent:2.08 vs.1.30 for BA growth).Sustained BA growth and accelerating wood/C growth contradict the common assumption that tree growth declines in bigger trees.Yield tables and silvicultural guidelines should be updated to reflect these current relationships.Such revisions will favor delaying harvests in many managed stands to increase wood production and enhance ecosystem values including C fxation and storage.Further research may resolve the relative roles of thinning,climatic conditions,nitrogen inputs,and rising CO2 levels on changing patterns of tree growth. 展开更多
关键词 tree growth Forest carbon tree allometry Diameter at breast height(DBH) Basal area(BA)increment Carbon sequestration Functional trait
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Anatomical mapping of GFAP-immunoreactive astrocytes in the tree shrew brain
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作者 Ya-Tao Wang Qi-Qi Xu +10 位作者 Shuo-Wen Wang Jin-Kun Guo Shuai-Deng Wang Xin-Ya Qin Qing-Hong Shan Yu Wang Rong-Yu Liu Yue-Xiong Yang Chen-Wei Wang Peng Chen Jiang-Ning Zhou 《Zoological Research》 2025年第4期877-892,共16页
Astrocytes are associated with varying brain size between rodents and primates.As a close evolutionary relative of primates,the tree shrew(Tupaia belangeri)provides a valuable comparative model for investigating glial... Astrocytes are associated with varying brain size between rodents and primates.As a close evolutionary relative of primates,the tree shrew(Tupaia belangeri)provides a valuable comparative model for investigating glial architecture.However,the anatomical distribution and morphological characteristics of astrocytes in the tree shrew brain remain poorly characterized.In this study,glial fibrillary acidic protein(GFAP)immunofluorescence was employed to systematically examine the spatial distribution and morphology of astrocytes in the whole brain of tree shrews.Notably,GFAP-immunoreactive(ir)astrocytes were detected throughout the telencephalon,diencephalon,mesencephalon,metencephalon,and myelencephalon.Distinct laminar distribution was evident in regions such as the main olfactory bulb and hippocampus.Semi-quantitative comparisons revealed significant regional differences in astrocyte density between tree shrews and mice,encompassing the main olfactory bulb,accessory olfactory bulb,olfactory tubercle,cortex,hippocampus,cortical amygdaloid nucleus,hypothalamus,thalamus,superior colliculus,interpeduncular nucleus,median raphe nucleus,and parabrachial nucleus.Compared to mice,tree shrews exhibited higher astrocyte density with increased morphological complexity in the posterior hypothalamic nucleus,dorsomedial hypothalamic nucleus,ventromedial hypothalamic nucleus,and periaqueductal gray,but lower density with greater morphological complexity in the hippocampus and substantia nigra.In the paraventricular hypothalamic nucleus and lateral hypothalamic area,GFAP-ir astrocytes displayed comparable densities between tree shrews and mice but exhibited region-specific differences in morphological complexity.This study provides the first brain-wide mapping of GFAP-ir astrocytes in tree shrews,revealing marked interspecies differences in their distribution and morphology,and establishing a neuroanatomical framework for understanding astrocyte involvement in diverse physiological and behavioral functions. 展开更多
关键词 tree shrews ASTROCYTES Morphology HIPPOCAMPUS HYPOTHALAMUS
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Properties of ions may explain elemental stoichiometry in late-and early-wood:a case study in Scots pine tree rings
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作者 Vladimir L.Gavrikov Ruslan A.Sharafutdinov +1 位作者 Alexey I.Fertikov Eugene A.Vaganov 《Journal of Forestry Research》 2025年第1期493-504,共12页
Understanding why elements are distributed in tree xylem in a particular way is a significant challenge in dendrochemistry.This study explored a hypothesis that metal elements in the xylem interact due to differences ... Understanding why elements are distributed in tree xylem in a particular way is a significant challenge in dendrochemistry.This study explored a hypothesis that metal elements in the xylem interact due to differences in physical properties such as ionic radius and ionization potential.Scots pine in an even-aged stand established during the early 1970s in eastern Siberia was the study species.Increment cores were taken from the north and south sides of trees and scanned with an X-ray fluorescent multi scanner.With the help of X-ray scanning,the following elements were analyzed:aluminum(Al),potassium(K),calcium(Ca),titanium(Ti),manganese(Mn),iron(Fe),copper(Cu),strontium(Sr)and zinc(Zn).Scanning data on the elements were split into early-wood and late-wood data for each year of growth.The following ratios were analyzed:Ca/Sr,Fe/Ca,Fe/Sr,Al/Cu,Al/Zn,Ti/Mn,and Mn/K.Among these,ones having a consistent pattern across tree rings,the ratios show a more or less dependable relationship:that an element shows a larger decrease(relative another element)that has a larger ionic radius and lower ionization potential.Hypothetically,this may be due to the advantage of an ion with smaller ionic radius and higher ionization potential under a deficit of accommodation centers in organic molecules.An experiment approach should be applied to clarify the relationships. 展开更多
关键词 Dendrochemistry tree rings Early-wood Late-wood Scots pine
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