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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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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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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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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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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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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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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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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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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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Possibilities of native endophytic fungi as entomopathogenic biocontrol agents at a local scale:the case of deciduous and non-deciduous Mediterranean forest trees
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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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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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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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Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests
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作者 Yue Chen Zikun Mao +2 位作者 Jonathan A.Myers Jinghua Yu Xugao Wang 《Forest Ecosystems》 SCIE CSCD 2024年第4期448-456,共9页
Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these f... Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM trees.To test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(i.e.total aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon stocks.However,biodiversity and environmental factors had opposite effects on AM vs.EM tree carbon stocks.Specifically,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon stocks.Environmental heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon stocks.Consequently,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment effect.This is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM vs.EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified.In summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests. 展开更多
关键词 BIODIVERSITY Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock
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Role of outdoor trees on pedestrian wind and thermal conditions around a pre-education building for sustainable energy management
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作者 LI Xiao-jie TANG Hui-li 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2039-2053,共15页
Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian... Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian-level wind velocity and thermal condition.In this study,a numerical investigation is employed to assess the role of trees planted in the windward direction of the building complex on the thermal and pedestrian wind velocity conditions around/inside a pre-education building located in the center of the complex.Compared to the previous studies(which considered only outside buildings),this work considers the effects of trees on microclimate change both inside/outside buildings.Effects of different parameters including the leaf area density and number of trees,number of rows,far-field velocity magnitude,and thermal condition around the main building are assessed.The results show that the flow velocity in the spacing between the first-row buildings is reduced by 30%-40% when the one-row trees with 2 m height are planted 15 m farther than the buildings.Furthermore,two rows of trees are more effective in higher velocities and reduce the maximum velocity by about 50%.The investigation shows that trees also could reduce the temperature by about 1℃around the building. 展开更多
关键词 sustainable management energy trees urban area thermal condition building
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Enhanced Cooling Efficiency of Urban Trees on Hotter Summer Days in 70 Cities of China
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作者 Limei YANG Jun GE +4 位作者 Yipeng CAO Yu LIU Xing LUO Shiyao WANG Weidong GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2259-2275,共17页
Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter d... Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter days, depending on the physiological response of urban trees to rising ambient temperature. However, the response of urban trees' cooling efficiency to rising urban temperature remains poorly quantified for China's cities. In this study, we quantify the response of urban trees' cooling efficiency to rising urban temperature at noontime [~1330 LT(local time), LT=UTC+8] in 17summers(June, July, and August) from 2003–19 in 70 economically developed cities of China based on satellite observations. The results show that urban trees have stronger cooling efficiency with increasing temperature, suggesting additional cooling benefits provided by urban trees on hotter days. The enhanced cooling efficiency values of urban trees range from 0.002 to 0.055℃ %-1 per 1℃ increase in temperature across the selected cities, with larger values for the lowTCP-level cities. The response is also regulated by background temperature and precipitation, as the additional cooling benefit tends to be larger in warmer and wetter cities at the same TCP level. The positive response of urban trees' cooling efficiency to rising urban temperature is explained mainly by the stronger evapotranspiration of urban trees on hotter days.These results have important implications for alleviating urban heat risk by utilizing urban trees, particularly considering that extreme hot days are becoming more frequent in cities under global warming. 展开更多
关键词 urban trees cooling efficiency China's cities EVAPOTRANSPIRATION SUMMER hot days
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Trees support functional soils in a dryland agricultural area
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作者 Jingyi Ding David J.Eldridge 《Geography and Sustainability》 CSCD 2024年第4期588-596,共9页
Trees provide multiple ecosystem services such as carbon sequestration,hydrological regulation and habitat for arboreal animals.However,they are often removed to support agricultural enterprises.Despite the importance... Trees provide multiple ecosystem services such as carbon sequestration,hydrological regulation and habitat for arboreal animals.However,they are often removed to support agricultural enterprises.Despite the importance of tree remnants,we know relatively little about how soils differ across sites of varying condition.Here,we describe a study where we examined the relative effects of trees,compared with unvegetated interspaces,on soil functions in remnant patches at sites in good and poor condition in two eucalypt communities in an irrigation area in eastern Australia.We found that,in general,carbon and nutrient cycling were relatively greater beneath trees,and in surface soils,but there were no clear trends in relation to site condition.The values of most soil attributes(e.g.,soluble and exchangeable cations,nitrogen,phosphorus)were greater beneath trees,indicating strong fertile island effects in both communities.Overall,our study confirms the importance of trees in remnant patches in agricultural landscapes,particularly those in sites of poor condition.It also suggests that soil processes may still be relatively intact,even in sites in poor condition.Our study reinforces the need to protect trees in remnant woodland reserves to maintain critical ecosystem functions related to nutrient retention.These remnants are important for achieving sustainable management of agricultural systems. 展开更多
关键词 CONDITION EUCALYPTUS Fertile islands Soil function trees WOODLANDS
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Intelligent evaluation of mean cutting force of conical pick by boosting trees and Bayesian optimization
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作者 LIU Zi-da LIU Yong-ping +3 位作者 SUN Jing YANG Jia-ming YANG Bo LI Di-yuan 《Journal of Central South University》 CSCD 2024年第11期3948-3964,共17页
Conical picks are important tools for rock mechanical excavation.Mean cutting force(MCF)of conical pick determines the suitability of the target rock for mechanical excavation.Accurate evaluation of MCF is important f... Conical picks are important tools for rock mechanical excavation.Mean cutting force(MCF)of conical pick determines the suitability of the target rock for mechanical excavation.Accurate evaluation of MCF is important for pick design and rock cutting.This study proposed hybrid methods composed of boosting trees and Bayesian optimization(BO)for accurate evaluation of MCF.220 datasets including uniaxial compression strength,tensile strength,tip angle(θ),attack angle,and cutting depth,were collected.Four boosting trees were developed based on the database to predict MCF.BO optimized the hyper-parameters of these boosting trees.Model evaluation suggested that the proposed hybrid models outperformed many commonly utilized machine learning models.The hybrid model composed of BO and categorical boosting(BO-CatBoost)was the best.Its outstanding performance was attributed to its advantages in dealing with categorical features(θincluded 6 types of angles and could be considered as categorical features).A graphical user interface was developed to facilitate the application of BO-CatBoost for the estimation of MCF.Moreover,the influences of the input parameters on the model and their relationship with MCF were analyzed.Whenθincreased from 80°to 90°,it had a significant contribution to the increase of MCF. 展开更多
关键词 rock cutting conical pick mean cutting force boosting trees Bayesian optimization
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Advances in Molecular Regulatory Mechanisms of Fruit Trees under Low Temperature Stress
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作者 Huan LIU Lijuan GAO +3 位作者 Minghui JI Longfei LI Jintao XU Baofeng HAO 《Plant Diseases and Pests》 2024年第3期46-48,共3页
The most recent research findings on the tolerance of fruit trees to cold stress are reviewed from a molecular perspective,including the perception and transduction of low temperature calcium signaling,CBF-dependent m... The most recent research findings on the tolerance of fruit trees to cold stress are reviewed from a molecular perspective,including the perception and transduction of low temperature calcium signaling,CBF-dependent molecular regulatory mechanisms,non-CBF-dependent molecular regulatory mechanisms,and so forth.The objective is to provide a reference basis for further improving the cold resistance of fruit trees and cultivating new varieties of hardy plants. 展开更多
关键词 Low temperature stress Fruit trees Growth and development Molecular mechanism Research progress
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Research and Application Effects of Biochar-based Fertilizer on Fruit Trees
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作者 Hui JIANG Xiaowei WU +4 位作者 Xingfang QIU Cuie CHEN Hailiang LU Yaohao WU Qianhua JI 《Asian Agricultural Research》 2024年第12期30-35,39,共7页
Biochar and biochar-based fertilizer are effective ways to realize the resource utilization of agricultural and forestry wastes.Because of its soil improvement,yield increase,quality improvement and significant enviro... Biochar and biochar-based fertilizer are effective ways to realize the resource utilization of agricultural and forestry wastes.Because of its soil improvement,yield increase,quality improvement and significant environmental effects,it has become a research hotspot,and its application in agriculture has also increased.In this paper,the preparation,types,application methods and effects of biochar-based fertilizer on fruit trees were summarized.Finally,this paper discussed the application prospects of biochar-based fertilizer on fruit trees. 展开更多
关键词 Biochar-based fertilizer Fruit trees Fertilizer application method Application effects
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Automated extraction and validation of Stone Pine(Pinus pinea L.)trees from UAV-based digital surface models
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作者 Asli Ozdarici-Ok Ali Ozgun Ok +1 位作者 Mustafa Zeybek Ayhan Atesoglu 《Geo-Spatial Information Science》 CSCD 2024年第1期142-162,共21页
Stone Pine(Pinus pinea L.)is currently the pine species with the highest commercial value with edible seeds.In this respect,this study introduces a new methodology for extracting Stone Pine trees from Digital Surface ... Stone Pine(Pinus pinea L.)is currently the pine species with the highest commercial value with edible seeds.In this respect,this study introduces a new methodology for extracting Stone Pine trees from Digital Surface Models(DSMs)generated through an Unmanned Aerial Vehicle(UAV)mission.We developed a novel enhanced probability map of local maxima that facilitates the computation of the orientation symmetry by means of new probabilistic local minima information.Four test sites are used to evaluate our automated framework within one of the most important Stone Pine forest areas in Antalya,Turkey.A Hand-held Mobile Laser Scanner(HMLS)was utilized to collect the reference point cloud dataset.Our findings confirm that the proposed methodology,which uses a single DSM as an input,secures overall pixel-based and object-based F1-scores of 88.3%and 97.7%,respectively.The overall median Euclidean distance revealed between the automatically extracted stem locations and the manually extracted ones is computed to be 36 cm(less than 4 pixels),demonstrating the effectiveness and robustness of the proposed methodology.Finally,the comparison with the state-of-the-art reveals that the outcomes of the proposed methodology outperform the results of six previous studies in this context. 展开更多
关键词 Stone pine trees Pinus pinea Digital Surface Model(DSM) Unmanned Aerial Vehicle(UAV) enhanced local maxima probabilistic local minima
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