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Exploring the boost by dominant ectomycorrhizal trees to soil organic carbon sequestration in the subtropical forest of the Jiulianshan National Nature Reserve
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作者 Yuandong Cheng Junjie Huang +7 位作者 Sili Wang Kun Xiong Kuan Liang Fangchao Wang Shengnan Wang Heping Zhang G.Geoff Wang Fusheng Chen 《Journal of Forestry Research》 2026年第2期172-184,共13页
Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in ... Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in subtropical forests.However,the consequences of this shift for soil organic carbon is poorly understood.To address this,a field study was conducted across a natural gradient of arbuscular tree associations to investigate how different mycorrhizal associations affect soil organic carbon quantity,composition,chemical stability,and related soil properties.Soil organic carbon fractions,functional groups,microbial enzyme activities were analyzed.Results showed that increasing arbuscular mycorrhizal dominance was associated with declines in total soil organic carbon,particularly in recalcitrant and aromatic carbon forms.Ectomycorrhizaldominated forests exhibited higher nitrogen availability and elevated nitrogen-hydrolyzing enzyme activity,suggesting enhanced nitrogen acquisition strategies that suppress soil organic carbon decomposition and promote carbon retention.These findings indicate that mycorrhizal-mediated shifts in tree composition may significantly alter soil carbon sequestration potential.Incorporating mycorrhizal functional traits into forest management and carbon modeling could improve predictions of soil organic carbon responses under future environmental change. 展开更多
关键词 Arbuscular mycorrhizal trees Ectomycorrhizal trees Soil organic carbon pool Nitrogen hydrolase activity
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Height-based biomass models differ for naturally regenerated and planted young trees
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作者 Peter Marcis Jozef Pajtík +1 位作者 Bohdan Konôpka Martin Lukac 《Forest Ecosystems》 2026年第1期178-187,共10页
This study investigated biomass allocation in young stands of European beech(Fagus sylvatica L.)and Norway spruce(Picea abies(L.)Karst.)across 31 forest sites in the Western Carpathians,Slovakia.A total of 541 trees a... This study investigated biomass allocation in young stands of European beech(Fagus sylvatica L.)and Norway spruce(Picea abies(L.)Karst.)across 31 forest sites in the Western Carpathians,Slovakia.A total of 541 trees aged 2–10 years,originating from natural regeneration and planting,were destructively sampled to quantify biomass in four components:foliage,branches,stems,and roots.Generalized non-linear least squares(GNLS)models with a weighing variance function outperformed log-transformed seemingly unrelated regression(SUR)models in terms of accuracy and robustness,especially for foliage and branch biomass.When using height as the predictor,SUR models tended to underestimate biomass in planted beech,leading to notable underprediction of aboveground and total biomass.Biomass allocation patterns varied significantly by species and regeneration origin.Using a non-linear system of equations and component ratio modelling,we found out that planted spruce displayed low variability and a consistent dominance of needle biomass,while naturally regenerated beech showed greater variability and a higher proportion of stem biomass,reflecting stronger competition-driven vertical growth.Interspecific differences in total biomass were more pronounced when using tree height,with spruce generally exhibiting greater biomass than beech at equivalent heights.Overall,stem base diameter marginally outperformed tree height as a predictor of biomass.However,tree height-based models showed strong performance and are particularly suitable for integration with remote sensing applications.These findings can directly support forest managers and modellers in comparing regeneration methods and biomass estimation approaches for early-stage stand development,carbon accounting,and remote sensing calibration. 展开更多
关键词 European beech Norway spruce Allometric relations Tree height Diameter at base Whole-tree biomass Tree components
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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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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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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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The Climate Change Influences on the Trees and a Life of Men in the Mekong River Delta-Remedial Actions
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作者 An Nguyen Thi Ngoc Trang Huynh Nguyen Thuy 《Journal of Environmental Science and Engineering(A)》 2025年第4期192-196,共5页
Mekong River Delta has many home-gardens,here,everybody organizes the tourisms.We observed the real situations and substances,evaluation,a choice at some households in the Mekong River Delta in order to have a purpose... Mekong River Delta has many home-gardens,here,everybody organizes the tourisms.We observed the real situations and substances,evaluation,a choice at some households in the Mekong River Delta in order to have a purpose of search,here,they have the home-gardens;the farmers plant fruit trees at the villages of provinces,that is a place which is influenced by the climate change.We went to the villages such as:Hiep Thanh village,Chau Thanh district,Long An province;Tan Phu village,Tan Phu Dong district,Tien Giang province;Tieu Can village,Tieu Can district,Tra Vinh province to observe the landscape(here 10 households for 1 village),and we took the sample to analyze.We knew the factors such as:drought,deficiency of water,salt water intrusion,flood.These factors influence the trees,assets,diseases,lives of the persons who stay here,and cause many damages.We compare many home-gardens having a climate change with the normal home-gardens.Thus,we propose the reasonable methods in order to fix the consequence and prevent the salt intrusion,flood,important damages…And we present some illustrations. 展开更多
关键词 Climate change trees MEN home-gardens
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The winter magic of trees: Dormancy
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作者 郝篆香 《疯狂英语(新悦读)》 2025年第3期44-46,77,共4页
1 Trees don't create their own heat like mammals do,and they don't have warm shelters or fur coats.So how do they survive the deep freeze of winter?In a way they do hibernate(冬眠)like bears—but in trees this... 1 Trees don't create their own heat like mammals do,and they don't have warm shelters or fur coats.So how do they survive the deep freeze of winter?In a way they do hibernate(冬眠)like bears—but in trees this is called dormancy and it's pretty amazing. 展开更多
关键词 DORMANCY trees winter survival
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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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面向电力载波通信网络的SPIHT 图像压缩算法研究
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作者 容达京 裘君 《物联网技术》 2025年第17期46-49,共4页
随着电力载波通信(PLC)在智能电网和物联网中的广泛应用,图像传输技术对效率和功耗的要求日益提高。然而,传统的图像压缩算法在PLC网络中进行图像传输时,面临带宽限制和数据冗余的问题。分层树集划分算法(SPIHT)作为一种高效的图像压缩... 随着电力载波通信(PLC)在智能电网和物联网中的广泛应用,图像传输技术对效率和功耗的要求日益提高。然而,传统的图像压缩算法在PLC网络中进行图像传输时,面临带宽限制和数据冗余的问题。分层树集划分算法(SPIHT)作为一种高效的图像压缩方法,具有优异的压缩性能和嵌入式比特流特性。然而,SPIHT在低码率下的压缩性能仍有提升空间。为此,提出了一种基于奇异值分解(SVD)的改进SPIHT图像压缩算法。首先,利用SVD对图像进行降噪和初步压缩;随后,采用SPIHT算法对处理后的图像进行高效编码,生成嵌入式比特流。实验结果表明,在低码率条件下,改进的SPIHT算法在峰值信噪比(PSNR)和结构相似性指数(SSIM)两个方面均表现出优于传统SPIHT算法的效果,显著提高了图像传输的效率和质量,为PLC网络中的图像传输提供了一种新的高效解决方案。 展开更多
关键词 电力载波通信网络 图像压缩 spiht 奇异值分解 图像编码 图像传输
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Application and Prospects of CRISPR/Cas9 Genome Editing Technology in the Genetic Improvement of Fruit Trees
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作者 Xiaoqi CHEN Shaoping WU 《Asian Agricultural Research》 2025年第6期40-46,共7页
CRISPR/Cas9 technology, a revolutionary gene-editing tool, has rapidly garnered attention in plant science owing to its simplicity, high editing efficiency, and cost-effectiveness. Besides, it offers unprecedented pre... CRISPR/Cas9 technology, a revolutionary gene-editing tool, has rapidly garnered attention in plant science owing to its simplicity, high editing efficiency, and cost-effectiveness. Besides, it offers unprecedented precision and efficiency in the genetic improvement of fruit trees. To date, this technology has been widely utilized to enhance fruit quality, improve stress resistance, and mediate growth and development. These applications demonstrate its immense potential in fruit tree breeding. Looking ahead, advancements in editing efficiency, expanded application scopes, comprehensive safety assessments, and improved regulatory frameworks are expected to further broaden the role of CRISPR/Cas9 in fruit tree breeding, thereby driving the fruit tree industry toward higher yield, superior quality, enhanced stress resilience, higher efficiency, and contributing to global food security and sustainable agricultural development. This article outlines the fundamental principles of CRISPR/Cas9 gene editing technology, its applications in plants (including fruit trees), and its pivotal role in genetic improvement and germplasm innovation. 展开更多
关键词 CRISPR/Cas9 Genome editing Fruit trees Genetic improvement Germplasm enhancement
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Evolving adaptive and interpretable decision trees for cooperative submarine search
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作者 Yang Gao Yue Wang +3 位作者 Lingyun Tian Xiaotong Hong Chao Xue Dongguang Li 《Defence Technology(防务技术)》 2025年第6期83-94,共12页
System upgrades in unmanned systems have made Unmanned Aerial Vehicle(UAV)-based patrolling and monitoring a preferred solution for ocean surveillance.However,dynamic environments and large-scale deployments pose sign... System upgrades in unmanned systems have made Unmanned Aerial Vehicle(UAV)-based patrolling and monitoring a preferred solution for ocean surveillance.However,dynamic environments and large-scale deployments pose significant challenges for efficient decision-making,necessitating a modular multiagent control system.Deep Reinforcement Learning(DRL)and Decision Tree(DT)have been utilized for these complex decision-making tasks,but each has its limitations:DRL is highly adaptive but lacks interpretability,while DT is inherently interpretable but has limited adaptability.To overcome these challenges,we propose the Adaptive Interpretable Decision Tree(AIDT),an evolutionary-based algorithm that is both adaptable to diverse environmental settings and highly interpretable in its decision-making processes.We first construct a Markov decision process(MDP)-based simulation environment using the Cooperative Submarine Search task as a representative scenario for training and testing the proposed method.Specifically,we use the heat map as a state variable to address the issue of multi-agent input state proliferation.Next,we introduce the curiosity-guiding intrinsic reward to encourage comprehensive exploration and enhance algorithm performance.Additionally,we incorporate decision tree size as an influence factor in the adaptation process to balance task completion with computational efficiency.To further improve the generalization capability of the decision tree,we apply a normalization method to ensure consistent processing of input states.Finally,we validate the proposed algorithm in different environmental settings,and the results demonstrate both its adaptability and interpretability. 展开更多
关键词 Cooperative decision making Interpretable decision trees Cooperative submarine search Maritime unmanned systems
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Mangrove Trees also Release Climate-Warming Methane
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《Bulletin of the Chinese Academy of Sciences》 2025年第4期210-210,共1页
Mangrove ecosystems are celebrated as powerful carbon sinks,absorbing and storing atmospheric CO_(2) more efficiently than most terrestrial forests.However,they also release methane-a greenhouse gas far more potent th... Mangrove ecosystems are celebrated as powerful carbon sinks,absorbing and storing atmospheric CO_(2) more efficiently than most terrestrial forests.However,they also release methane-a greenhouse gas far more potent than carbon dioxide.A study published in Nature Geoscience(doi:10.1038/s41561-025-01848-4)on November 14 reveals that mangrove tree stems represent a previously overlooked pathway of methane emissions,partially reducing the climate benefits of these coastal ecosystems. 展开更多
关键词 carbon sinksabsorbing nature geoscience doi s carbon dioxidea coastal ecosystems mangrove trees carbon sinks greenhouse gas methane emissions
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Lifespan of tropical trees from seed to 1-cm diameter
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作者 Richard Condit Andrés Hernández +5 位作者 Oswaldo Calderón Rolando Pérez Salomón Aguilar Liza S.Comita Stephen P.Hubbell S.Joseph Wright 《Forest Ecosystems》 2025年第3期551-560,共10页
Background The full lifespan of long-lived trees includes a seedling phase,during which a seed germinates and grows to a size large enough to be measured in forest inventories.Seedling populations are usually studied ... Background The full lifespan of long-lived trees includes a seedling phase,during which a seed germinates and grows to a size large enough to be measured in forest inventories.Seedling populations are usually studied separately from adult trees,and the seedling lifespan,from seed to sapling,is poorly known.In the 50-ha Barro Colorado forest plot,we started intensive censuses of seeds and seedlings in 1994 in order to merge seedling and adult demography and document complete lifespans.Methods In 17 species abundant in seedling censuses,we subdivided populations into six size classes from seed to 1cm dbh,including seeds plus five seedling stages.The smallest seedling class was subdivided by age.Censuses in two consecutive years provided transition matrices describing the probability that a seedling in one stage moved to another one year later.For each species,we averaged the transition matrix across 25 censuses and used it to project the seedling lifespan,from seed until 1cm dbh or death.Results The predicted mean survival rate of seeds to 1cm dbh varied 1000-fold across species,from 2.9×10^(−6)to 4.4×10^(−3);the median was 2.0×10^(−4).The seedling lifespan,or the average time it takes a seed to grow to 1cm dbh,varied across species from 5.1 to 53.1 years,with a median of 20.3 years.In the median species,the 10%fastest-growing seeds would reach 1cm dbh in 9.0 years,and the slowest 10%in 34.6 years.Conclusions Combining seedling results with our previous study of lifespan after 1cm dbh,we estimate that the focal species have full lifespans varying from 41 years in a gap-demanding pioneer to 320 years in one shade-tolerant species.Lifetime demography can contribute precise survival rates and lifespans to forestry models. 展开更多
关键词 survival rate document complete lifespansmethods species variation forest plot seedling stage demographic transition merge seedling adult demography tree growth
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Assessment of the heartwood contribution to carbon accumulation in Pinus sylvestris L.trees under different forest site conditions
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作者 Natalia A.Galibina Kseniya M.Nikerova +1 位作者 Sergey A.Moshnikov Alexander M.Kryshen 《Forest Ecosystems》 2025年第1期159-175,共17页
Background:The heartwood(HW)proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration.We have for the first tim... Background:The heartwood(HW)proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration.We have for the first time studied the proportion of HW in the trunk and the distribution of carbon and extractives in sapwood(SW)and HW of 70–80 year old Pinus sylvestris L.trees under different growing conditions in the pine forests of North-West Russia.Method:We have examined the influence of conditions and tree position in stand(dominant,intermediate and suppressed trees)in the ecological series:blueberry pine forest(Blu)–lingonberry pine forest(Lin)–lichen pine forest(Lic).We have analyzed the influence of climate conditions in the biogeographical series of Lin:the middle taiga subzone–the northern taiga subzone–the transition area of the northern taiga subzone and tundra.Results:We found that the carbon concentration in HW was 1.6%–3.4%higher than in SW,and the difference depended on growing conditions.Carbon concentration in HW increased with a decrease in stand productivity(Blu-Lin-Lic).In medium-productive stands,the carbon concentration in SW was higher in intermediate and supressed trees compared to dominant trees.In the series from south to north,carbon concentration in HW increased by up to 2%,while in SW,it rose by 2.7%–3.8%.Conclusions:Our results once again emphasized the need for an empirical assessment of the accurate carbon content in aboveground wood biomass,including various forest growing conditions,to better understand the role of boreal forests in carbon storage. 展开更多
关键词 Scots pine Blueberry pine forest Lingonberry pine forest Lichen pine forest Tree social class Climate Carbon content EXTRACTIVES Cellulose LIGNIN
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无人机作业参数对雾滴在桃树冠层沉积分布的影响
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作者 蒋三生 卜小东 +1 位作者 郭辉 蒋晓 《中国农机化学报》 北大核心 2026年第1期147-152,共6页
为优选出无人机针对桃树喷施作业的参数组合,以双旋翼农业无人机为作业平台,设置三因素三水平的正交试验,通过试验结果和极差分析研究作业高度、作业速度、喷施流量对雾滴沉积密度、均匀性和穿透性的影响规律和影响程度。结果表明:作业... 为优选出无人机针对桃树喷施作业的参数组合,以双旋翼农业无人机为作业平台,设置三因素三水平的正交试验,通过试验结果和极差分析研究作业高度、作业速度、喷施流量对雾滴沉积密度、均匀性和穿透性的影响规律和影响程度。结果表明:作业高度H为3.5 m、作业速度V为2.5 m/s、喷施流量T为72 L/hm^(2)时,雾滴的沉积密度最佳,平均为34.03个/cm^(2),同时具有较好的沉积均匀性和穿透性;桃树上层沉积密度的较优因素水平:H=3.5 m、V=2.5 m/s、T=108 L/hm^(2),沉积分布均匀性的较优因素水平:H=4.0 m、V=2.0 m/s、T=72 L/hm^(2);桃树中、下层沉积密度的较优因素水平:H=4.0 m、V=2.5 m/s、T=72 L/hm^(2),中层沉积分布均匀性的较优因素水平:H=4.0 m、V=1.5 m/s、T=72 L/hm^(2),下层沉积分布均匀性的较优因素水平:H=3.5 m、V=2.5 m/s、T=90 L/hm^(2);雾滴沉积穿透性的较优因素水平:H=3.5 m、V=2.0 m/s、T=108 L/hm^(2);影响雾滴沉积效果的主次顺序在树冠上、中、下3个高度层均呈现不同的结果。综合对比发现,作业高度对喷施雾滴的沉积密度和沉积均匀性影响最大,作业速度次之,喷施流量的影响最小;影响雾滴沉积密度穿透性大小的因素主次顺序为喷施流量、作业高度、作业速度。试验结果可为农业无人机在果树产业中的绿色飞防应用和发展提供理论依据。 展开更多
关键词 无人机 作业参数 雾滴 沉积分布 桃树
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基于树木雷达的古槐树根系分布特征
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作者 卢伟娜 刘怡芸 +4 位作者 孙悦 夏爽 各如灿 李济菲 王旭东 《林业勘查设计》 2026年第1期82-86,共5页
古树是岁月里走来的绿色文物,承载深厚的文化内涵和历史底蕴,是自然历史进化过程中的瑰宝。古树根系健康状况对树木后期的保护与发展起到关键作用,选取不同立地条件下树龄为600 a与700 a的一级古树为研究对象,利用树木雷达检测系统,采... 古树是岁月里走来的绿色文物,承载深厚的文化内涵和历史底蕴,是自然历史进化过程中的瑰宝。古树根系健康状况对树木后期的保护与发展起到关键作用,选取不同立地条件下树龄为600 a与700 a的一级古树为研究对象,利用树木雷达检测系统,采用环状放线测量方式对古树根系进行无伤探测,得出树木直径不小于2 cm的粗根数量及分布情况。研究结果表明,在垂直方向上,古树的根系分布密度随深度的增加而先增加后减少,且集中分布在20~40 cm的区域。水平方向上,根系分布密度随着与根基距离的增加而减少,且根系分布密度最高处位于距离根基1 m处。硬质铺装和自然条件2种立地环境下,自然条件下的古树根系密度显著高于铺装压迫下的根系密度。结果显示采用树木雷达研究古树根系具有较强的可行性和合理性,为后期有针对性地对古树进行保护与复壮提供科学依据和参考。 展开更多
关键词 根系分布 树木雷达 古树 粗根
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基于隶属函数法和VIKOR法的梨轻简化树形适宜品种综合评价
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作者 闫帅 相丛超 +5 位作者 李冰莹 赵亮亮 彭垲 徐功勋 赵德英 曹玉芬 《果树学报》 北大核心 2026年第3期569-577,共9页
【目的】探明适宜‘双臂顺行式’棚架轻简化栽培的优良梨品种,实现良种良法配套。【方法】以长江中下游产区采用的‘双臂顺行式’棚架栽培的代表性梨园的17个品种为研究对象,调查分析不同品种生长结果特性和果实品质指标差异,利用隶属... 【目的】探明适宜‘双臂顺行式’棚架轻简化栽培的优良梨品种,实现良种良法配套。【方法】以长江中下游产区采用的‘双臂顺行式’棚架栽培的代表性梨园的17个品种为研究对象,调查分析不同品种生长结果特性和果实品质指标差异,利用隶属函数法和VIKOR法对不同品种在‘双臂顺行式’棚架栽培下生长结果及果实品质进行综合评价。【结果】‘双臂顺行式’棚架栽培模式下不同品种成枝力、长枝比例、产量、结果枝数、固酸比、可滴定酸含量、果肉细度和耐咀嚼性8个指标变异系数较大,差异化明显;隶属函数法综合评价值在0.70以上的梨品种有4个:丰水、圆黄、翠冠、玉绿,鄂梨2号综合评价值略低,为0.691;通过VIKOR法评价可知,早果性的权重值最大,为19.3%,中短枝比率权重最小,为2.3%,综合排名前5位的是丰水、圆黄、翠冠、玉绿、鄂梨2号。【结论】隶属函数法与VIKOR法均可作为树形和品种适宜性综合评价的方法;丰水、圆黄、翠冠、玉绿,鄂梨2号可作为长江中下游产区适宜‘双臂顺行式’棚架栽培的优良品种。 展开更多
关键词 隶属函数法 VIKOR法 树形 品种 综合评价
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