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Impact of Fast-Growing Trees Planting on Degraded Land from Perspectives of Ecosystem Services—Case Study from Slovakia
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作者 Jarmila Makovníková Boris Pálka Stanislav Kološta 《Journal of Geoscience and Environment Protection》 2022年第11期140-150,共11页
The aim of the study was to assess the effect of natural phytoremediation, impact of growing fast-growing trees on contaminated agricultural land on ecosystem services using a Matrix evaluation system. The Matrix syst... The aim of the study was to assess the effect of natural phytoremediation, impact of growing fast-growing trees on contaminated agricultural land on ecosystem services using a Matrix evaluation system. The Matrix system is a table that links an ecosystem to its potential to provide ecosystem services. To determine the monetary price of natural capital for the provision of ecosystem services, we chose the value transfer method, based on which it is possible to assign a price (1 point = 40.7 EUR) to point values. Monitoring of the study site Kuchyňa (Mollic Fluvisol) is running since year 2010. The fast-growing willow was planted (between 2006 to 2018 year) on an area of about 43 hectares. During the monitoring of soil parameters, we observed a slight decrease in the value of the active soil reaction, a negative trend in the content of available phosphorus and a positive trend in the development of the total content risk elements in the soil. The phytoremediation ability of willow regarding risk elements was manifested by an increase in the value and price of production and regulatory ecosystem services at the monitored location. The price of natural phytoremediation of fast-growing willow on the given area was 218762.5 EUR for production services and 171509.8 EUR for regulatory services. 展开更多
关键词 Ecosystem Services Soil Parameters Fast Growing trees
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基于粒子索引排序算法的kd-tree缓存优化问题研究
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作者 张挺 林震寰 +2 位作者 杨丁颖 王宗锴 陈轶凡 《工程科学与技术》 北大核心 2026年第1期313-323,共11页
在使用kd-tree进行大规模随机粒子近邻搜索时,可能出现计算域内索引值相近的粒子在空间上距离较远而导致kd-tree搜索路径在短时间内产生较大差异等问题,使得节点数据的访问效率降低,最终影响kd-tree近邻搜索的效率。为解决该问题,本文... 在使用kd-tree进行大规模随机粒子近邻搜索时,可能出现计算域内索引值相近的粒子在空间上距离较远而导致kd-tree搜索路径在短时间内产生较大差异等问题,使得节点数据的访问效率降低,最终影响kd-tree近邻搜索的效率。为解决该问题,本文引入了主成分分析中最大离散度降维的思想,采用平均绝对差作为离散度衡量指标,提出了基于平均绝对差粒子索引值排序的缓存优化策略MAD-index-sort,通过计算粒子集群平均绝对差最大的维度来实现数据降维,进而完成粒子的索引值重排序,并应用具有自动终止准则的ATC-kd-tree进行近邻搜索。为验证MADindex-sort缓存优化策略的可行性,设计了不同维度和离散度对照组进行近邻搜索效率对比实验。结果表明,MADindex-sort能根据粒子集群的离散度自动改变排序方向,具有更强的适应性,相较于未排序的情况性能最高可提升30.3%。 展开更多
关键词 KD-tree 粒子近邻搜索 缓存优化 粒子索引值排序
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Carbon storage in biomass,litter,and soil of different native and introduced fast-growing tree plantations in the South Caspian Sea 被引量:4
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作者 Jamshid Eslamdoust Hormoz Sohrabi 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期444-452,共9页
Replantation of degraded forest using rapidgrowth trees can play a significant role in global carbon budget by storing large quantities of carbon in live biomass,forest floor,and soil organic matter.We assessed the po... Replantation of degraded forest using rapidgrowth trees can play a significant role in global carbon budget by storing large quantities of carbon in live biomass,forest floor,and soil organic matter.We assessed the potential of 20-year old stands of three rapid-growth tree species,including Alnus subcordata,Populus deltoides and Taxodium distichum,for carbon(C) storage at ecosystem level.In September 2013,48 replicate plots(16 m × 16 m) in 8 stands of three plantations were established.36 trees were felled down and fresh biomass of different components was weighed in the field.Biomass equations were fitted using data based on the 36 felled trees.The biomass of understory vegetation and litter were measured by harvesting all the components.The C fraction of understory,litter,and soil were measured.The ecosystem C storage was as follows: A.subcordata(626.5 Mg ha) [ P.deltoides(542.9Mg ha) [ T.distichum(486.8 Mg ha)(P \ 0.001),of which78.1–87.4% was in the soil.P.deltoides plantation reached the highest tree biomass(206.6 Mg ha),followed by A.subcordata(134.5 Mg ha) and T.distichum(123.3 Mg ha).The highest soil C was stored in theplantation of A.subcordata(555.5 Mg ha).The C storage and sequestration of the plantations after 20 years were considerable(25–30 Mg hayear) and broadleaves species had higher potential.Native species had a higher soil C storage while the potential of introduced species for live biomass production was higher. 展开更多
关键词 BIOMASS Carbon storage Climate change MONOCULTURE tree allometry Soil carbon
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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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Characterization of Gut and Gill Microbiomes in Fast-Growing Pacific White Shrimp Penaeus vannamei
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作者 FU Zhenqiang CHEN Qinglong +3 位作者 YE Yinjun ZHAO Huixin LIN Genmei LU Jianguo 《Journal of Ocean University of China》 2025年第5期1386-1400,共15页
The relationship between microbial communities and their hosts is important to the health and productivity of marine ani-mals in aquaculture.This study investigated the microbiomes in the gut and gill of Penaeus vanna... The relationship between microbial communities and their hosts is important to the health and productivity of marine ani-mals in aquaculture.This study investigated the microbiomes in the gut and gill of Penaeus vannamei using 16S rRNA gene sequencing,comparing the microbial characteristics in the fast-growing trait and in the control group.Fast-growing individuals exhibited sig-nificantly different growth parameters and gut/gill microbiomes.Significantly higher weight gain and condition factors,as well as lower hepatosomatic indices(HSI),were observed in fast-growing individuals.Fast-growing individuals also displayed significantly higher operational taxonomic unit(OTU)counts(in gills)and greater phylogenetic diversity(PD)in both gut and gill microbiomes,while Lactobacillus was significantly more abundant and showed strong network centrality in the gut of this group.Furthermore,beta diversity analysis revealed significant differences in microbial community structure between the groups in both gut and gills.Functional predictions indicated increased activity in metabolic pathways(e.g.,carbon metabolism,protein export)in the fast-growing group,reflecting the adaptations to increased energy utilization.Conversely,other genera such as TM7a were found at significantly lower abundance in the fast-growing group and showed sig-nificant correlations with growth parameters,highlighting potential microbial indicators of different growth strategies or physiological trade-offs.These findings underscore the close relationship between microbial communities and the health and productivity of Penaeus vannamei.Future studies should focus on optimizing growth perfor-mance and balancing it with the immune robustness in P.vannamei. 展开更多
关键词 Penaeus vannamei microbial characterization growth performance fast-growing trait
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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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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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Functional relationships of nodulation response and biomass production at nursery stages of two fast-growing, leguminous-multipurpose tree species in Bangladesh: Albizia saman and Leucaena leucocephala
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作者 Md.Salim AZAD Samir MONDOL Md.Abdul MATIN 《Forestry Studies in China》 CAS 2013年第4期274-285,共12页
This study was carried out to assess the relationship of the status of nodulation(i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters(i.e., number of leaves, ro... This study was carried out to assess the relationship of the status of nodulation(i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters(i.e., number of leaves, root and shoot lengths, root biomass and shoot biomass) in Albizia saman and Leucaena leucocephala. The assessment started 60 days after seeding. The study revealed that nodulation response and biomass production in both species showed significant differences over time(p < 0.05) in all variables except in the root-shoot ratio(oven-dry) of L. leucocephala. The study also showed significant differences(p < 0.05) in nodule formation and biomass production at the end of the study period between the two species except in the number of nodules and leaves and the green root-shoot ratio. There were strong positive correlations between nodule formation and biomass production, i.e., the number of nodules and the age of plants, the number of nodules and leaves, as well as the number of nodules and biomass(root biomass and shoot biomass) in both species. The results obtained using principal component analysis(PCA) and correlation coefficients of the different characteristics of nodulation and biomass production were similar in both species. The PCA showed that shoot biomass(shoot green weight and shoot oven-dry weight) is positively correlated with PC1(with an eigenvalue of 7.50) and root length is positively correlated with PC2(with an eigenvalue of 0.19) in the case of A. saman. In the case of L. leucocephala, the PCA revealed that root biomass(root green weight and root oven-dry weight), shoot biomass and shoot length are also positively correlated with PC1, while nodule formation and the number of leaves are positively correlated with PC2(with an eigenvalue PC1 of 6.92 and PC2 of 0.49). 展开更多
关键词 leguminous tree species nitrogen fixation nodule formation nursery practice seedling growth
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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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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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Optimization models of stand structure and selective cutting cycle for large diameter trees of broadleaved forest in Changbai Mountain 被引量:6
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作者 郝清玉 周玉萍 +1 位作者 王立海 吴金卓 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期135-140,共6页
The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the d... The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the data from Hongshi Forestry Bureau, in Changbai Mountain region, Jilin Province, China. The data were measured in 232 permanent sample plots. With the data of permanent sample plots, the parameters of transition probability and ingrowth models were estimated, and some models were compared and partly modified. During the simulation of stand structure, four factors such as largest diameter residual tree (LDT), the ratio of the number of trees in a given diameter class to those in the next larger diameter class (q), residual basal area (RBA) and selective cutting cycle (C) were considered. The simulation results showed that the optimum stand structure parameters for large diameter trees are as follows: q is 1.2, LDT is 46cm, RBA is larger than 26 m^2 and selective cutting cycle time (C) is between 10 and 20 years. 展开更多
关键词 Large diameter tree Stand structure OPTIMIZATION Broad-leaved forest MODEL
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Review:effects of wind on trees 被引量:9
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作者 朱教君 刘足根 +2 位作者 MATSUZAKI Takeshi Gonda Yutaka Gonda Yutaka 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期153-160,i003,i004,共10页
Wind not only causes extensive damages to trees in many parts of the world, it also has more subtle effects on the growth and morphology of trees and forest ecology as well. Wind damage to trees has historically been ... Wind not only causes extensive damages to trees in many parts of the world, it also has more subtle effects on the growth and morphology of trees and forest ecology as well. Wind damage to trees has historically been the field of silviculture, but increasing recognition of the importance and complexity of the subject has recently got people involved from many other disciplines. Due to the global climate changes, it is believed that the risk of further and stronger storms is increasing. In order to better understand the effects of wind on individual trees, forest stand and forest ecosystem, and further to practice the management of forests, it is necessary to summarize the research results related to this subject. This review was mostly based on the references from recent researches in the field, especially from the symposium volumes of some international conferences on this subject. The results indicated that there have been significant progresses in the following aspects: 1) the aerodynamic interaction between wind and trees, 2) the mechanics of trees under wind loading and adaptive growth, 3) the tree's physiological responses to wind, and 4) the risk assessment of wind damage to forest. However, there are some aspects which may need further studies: 1) wind damage to natural forests, 2) wind-driven gap formation and forest dynamics, 3) the effects of changes resulted from wind disturbances on ecological processes of forest ecosystem, and 4) management for the wind-damaged forests. Key words Wind - Wind effect - Trees/forest - Forest ecology - Disturbance CLC number S718 Document code B Foundation item: This research was supported by “the 100-Young-Researcher Project” of Chinese Academy of Sciences (BR0301) and National Natural Science Foundation (30371149).Biography: ZHU Jiao-jun (1965-), male, Ph. Doctor, Professor of Institute of Applied Ecology, Chinese Academy of Sciences, Professor of Graduate School of Chinese Academy of Sciences. China. Scholar researcher of Faculty of Agriculture, Niigata University, JapanResponsible editor: Song Funan 展开更多
关键词 WIND Wind effect trees/forest Forest ecology DISTURBANCE
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