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印支造山带:Song Chay构造带
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作者 林伟 王印 +4 位作者 刘飞 孟令通 吴钦颖 郭钊 李金雁 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第1期1-28,共28页
印支运动是二十世纪初法国地质学家根据越南北部晚三叠世大规模角度不整合所提出。越南北部的Song Chay构造带作为印支造山带概念的提出地,记录了大量经典的印支造山相关的信息,是理解印支造山带构造演化的关键地区。本文在课题组对Song... 印支运动是二十世纪初法国地质学家根据越南北部晚三叠世大规模角度不整合所提出。越南北部的Song Chay构造带作为印支造山带概念的提出地,记录了大量经典的印支造山相关的信息,是理解印支造山带构造演化的关键地区。本文在课题组对Song Chay地区十多年研究基础上,结合前人研究成果,系统厘定了Song Chay构造带的几何空间格架、运动学特征及其演化过程。详细的野外地质考察表明,Song Chay构造带从SW向NE依次可以划分成:新生代的大象山单元、代表缝合带的Song Chay蛇绿混杂岩单元,以及越南东北部褶皱冲断系统。其中蛇绿混杂岩单元和褶皱冲断系统中发育NE-SW向矿物拉伸线理,并具有顶部向NE方向的剪切变形特征,指示了Song Chay洋壳向SW的俯冲以及向NE的逆冲过程。精确的年代学工作表明,Song Chay蛇绿混杂岩中斜长花岗岩的结晶年龄为356.4±2.9Ma,表明至少在早石炭世Song Chay洋就已经形成了成熟的大洋地壳。褶皱冲断带内部的低温年代学数据约束了顶部向NE的剪切变形年龄在250~245Ma之间,表明为华南和印支板块碰撞时间。另外,Song Chay蛇绿混杂岩基质中碎屑锆石物源研究表明,Song Chay蛇绿混杂岩基质中碎屑锆石主要是来自于俯冲的华南板块,只有很少一部分来自印支板块,因此推测Song Chay洋可能为一个十分有限的小洋盆。构造几何学、运动学以及碎屑锆石物源研究表明,在Song Chay构造带内的“滇-琼缝合带”两侧构造特征可对比,并未因“滇琼洋”的闭合而造成差异。因此,我们认为“滇-琼缝合带”并不能代表一个大洋。根据我们及前人的构造学、岩石学、年代学工作,建立了一个初步的Song Chay洋从晚石炭世至中三叠世的构造演化模型:(1)310~270Ma,Song Chay洋开始向SW俯冲到印支板块之下,此时岩浆弧并不发育,蛇绿混杂岩物源主要为华南板块;(2)270~250Ma,Song Chay洋继续俯冲,此时弧岩浆岩大量发育,蛇绿混杂岩同时接受弧岩浆岩及华南板块碎屑物质;(3)250~245Ma,Song Chay洋闭合,华南板块与印支板块碰撞;(4)245~230Ma,印支造山带进入碰撞后伸展阶段。 展开更多
关键词 印支运动 song Chay构造带 构造解析 碎屑锆石 滇-琼缝合带
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Modifications in aroma characteristics of'Merlot'dry red wines aged in American,French and Slovakian oak barrels with different toasting degrees
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作者 Haocheng Lu Binhao Cheng +2 位作者 Yibin Lan Changqing Duan Fei He 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期381-391,共11页
Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermen... Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak aging.The fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel aromas.The concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak barrels.The concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting ones.The compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could not.The fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious. 展开更多
关键词 Wine Aroma oak Barrel oak species Toasting degrees Geographic origin Aging
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Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)
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作者 Ryan McClory Richard H.Ellis +5 位作者 Martin Lukac Jo Clark Carolina Mayoral Kris M.Hart Andrew R.G.Plackett A.Rob MacKenzie 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期1-12,共12页
Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commer... Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each year.Anthropogenic emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced photosynthesis.To examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) concentrations.Inter-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in 2018.The numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting Q.robur at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature acorns.The number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient plots.Enrichment with CO_(2) also increased the number of oak knopper galls(Andricus quercuscalicis Burgsdorf).We conclude that elevated CO_(2) increased the occurrence of acorns developing from flowers,but the putative benefit to mature acorn numbers may have been hidden by excessive pre-and/or post-dispersal predation.There was no evidence that elevated CO_(2) altered masting behaviour. 展开更多
关键词 Quercus robur L. ACORNS MASTING Pedunculate oak Carbon dioxide
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Economic significance and environmental impacts of the Song Dam Drinking Water Project(SDDWP)in Garhwal Himalaya
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作者 Vishwambhar Prasad SATI 《Regional Sustainability》 2024年第2期140-152,共13页
With the population growth through natural growth and migration,coupled with the city expansion,it is the fact that Dehradun City in India faces severe water scarcity.Therefore,the Song Dam Drinking Water Project(SDDW... With the population growth through natural growth and migration,coupled with the city expansion,it is the fact that Dehradun City in India faces severe water scarcity.Therefore,the Song Dam Drinking Water Project(SDDWP)is proposed to provide ample drinking water to Dehradun City and its suburban areas.This paper examined economic significance and environmental impacts of the SDDWP in Garhwal Himalaya,India.To conduct this study,we collected data from both primary and secondary sources.There are 12 villages and 3 forest divisions in the surrounding areas of the proposed dam project,of which 3 villages will be fully submerged and 50 households will be affected.For this study,50 heads of the households were interviewed in the 3 submerged villages.The questions mainly focused on economic significance,environmental impacts,and rehabilitation issues of the dam project.The findings of this study indicate that economic significance of the dam project is substantial,including providing ample water for drinking and irrigation,contributing to groundwater recharge,creating job opportunities,and promoting the development of tourism and fisheries in the Doon Valley.In terms of the rehabilitation of the affected people,there are only 50 households in need of rehabilitation.Currently,the arable land of these affected people is not sufficient to sustain their livelihoods.The entire landscape is fragile,rugged,and precipitous;therefore,the affected people are willing to rehabilitate to more suitable areas in the Doon Valley.Moreover,it is essential to provide them with sufficient compensation packages including the compensation of arable land,houses,cash,common property resources,institutions,belongingness,and cultural adaptation.On the other hand,the proposed dam project will have adverse environmental impacts including arable land degradation,forest degradation,loss of fauna and flora,soil erosion,landslides,and soil siltation.These impacts will lead to the ecological imbalances in both upstream and downstream areas.This study suggests that the affected people should be given sufficient compensation packages in all respects.Afforestation programs can be launched in the degraded areas to compensate for the loss of forest in the affected areas. 展开更多
关键词 Water scarcity Rehabilitation issues song Dam Drinking Water Project(SDDWP) Dehradun City song River BASIN
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Climate-change habitat shifts for the vulnerable endemic oak species(Quercus arkansana Sarg.)
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作者 Suresh Chandra Subedi Seth Drake +1 位作者 Binaya Adhikari Mark V.Coggeshall 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期117-127,共11页
Quercus arkansana(Arkansas oak)is at risk of becoming endangered,as the total known population size is represented by a few isolated populations.The potential impact of climate change on this species in the near futur... Quercus arkansana(Arkansas oak)is at risk of becoming endangered,as the total known population size is represented by a few isolated populations.The potential impact of climate change on this species in the near future is high,yet knowledge of its predicted effects is limited.Our study utilized the biomod2 R package to develop habi-tat suitability ensemble models based on bioclimatic and topographic environmental variables and the known loca-tions of current distribution of Q.arkansana.We predicted suitable habitats across three climate change scenarios(SSP1-2.6,SSP2-4.5,and SSP5-8.5)for 2050,2070,and 2090.Our findings reveal that the current suitable habitat for Q.arkansana is approximately 127,881 km^(2) across seven states(Texas,Arkansas,Alabama,Louisiana,Mississippi,Georgia,and Florida);approximately 9.5%is encompassed within state and federally managed protected areas.Our models predict that all current suitable habitats will disap-pear by 2050 due to climate change,resulting in a northward shift into new regions such as Tennessee and Kentucky.The large extent of suitable habitat outside protected areas sug-gests that a species-specific action plan incorporating pro-tected areas and other areas may be crucial for its conserva-tion.Moreover,protection of Q.arkansana habitat against climate change may require locally and regionally focused conservation policies,adaptive management strategies,and educational outreach among local people. 展开更多
关键词 Biomod2 Climate change CONSERVATION Habitat loss Habitat shift Species distribution modeling oak species
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Case Records as Medical Stories: A Song-dynasty Doctor’s Narration of His Own Medicine-Xu Shuwei (1080-1154)
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作者 Asaf Goldschmidt 《Chinese Medicine and Culture》 2024年第2期95-103,共9页
The key point in studying or teaching the history of Chinese medicine is on the doctrines underlying it and on its perception of the body,physiology,pathology,and its treatment.Namely,there is often a tendency to focu... The key point in studying or teaching the history of Chinese medicine is on the doctrines underlying it and on its perception of the body,physiology,pathology,and its treatment.Namely,there is often a tendency to focus on reading and analysing the classical canons and therapy-related texts including formularies and materia medica collections.However,focusing on these sources provides us with a one-sided presentation of Chinese medicine.These primary sources lack the clinical down-to-earth know-how that encompasses medical treatment,which are represented,for instance,in the clinical rounds of modern medical schools.Our traditional focus on the medical canons and formularies provides almost no clinical knowledge,leaving us with a one-sided narrative that ignores how medicine and healing are actually practiced in the field.This paper focuses on the latter aspect of medicine from a historical perspective.Using written and visual sources dating to the Song dynasty,clinical encounters between doctors and patients including their families are depicted based on case records recorded by a physician,members of the patient’s family,and bystanders.This array of case records or case stories will enable us to narrate the interaction between physicians and patients both from the clinical perspective and from the social interaction.This paper will also discuss visual depictions of the medical encounter to provide another perspective for narrating medicine during the Song dynasty.Medical case records and paintings depicting medical encounters are exemplary of the potential of Chinese primary sources for narrative medicine. 展开更多
关键词 Clinical encounter Medical practice song dynasty Xu Shuwei Case records
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Construction of the Genealogy of Eccentric Monks Based on the Historical Materials of Chan Buddhism in the Song Dynasty--From Enlightened Masters in Chan Buddhism,Sages,to Saints
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作者 Jing-Jia Huang 《Cultural and Religious Studies》 2024年第8期501-511,共11页
Regarding the Chan Buddhism lamp records from the Song Dynasty and starting from Jing De Zhuan Deng Lu,the category of“enlightened masters in Chan Buddhism”禪門達者was listed separately,meaning a separate category w... Regarding the Chan Buddhism lamp records from the Song Dynasty and starting from Jing De Zhuan Deng Lu,the category of“enlightened masters in Chan Buddhism”禪門達者was listed separately,meaning a separate category was established for eccentric monks who pretended to be crazy,had unknown inheritance and miraculous deeds,and were difficult to classify.The following lamp records named this category of eccentric monks as“sages”散聖,or“saints”應化聖賢,which constructed another historical genealogy for the special Chan Buddhism eccentric monks.Moreover,the early lamp records included mostly idiosyncratic mad monks from previous dynasties.Since the Southern Song Dynasty,Chan Buddhism historical materials included many sages from the current dynasty.Therefore,this study mainly examines how the genealogy of Chan Buddhism eccentric monks was constructed in Song Dynasty Chan Buddhism lamp records,including quotations,and organizes the images of eccentric monks in the Song Dynasty,as written in Chan Buddhism historical materials,in order that the meaning of existence of these enlightened masters,sages,saints,etc.,included in the genealogy of Song Dynasty eccentric monks in the history of Chan Buddhism can be reflected. 展开更多
关键词 genealogy of eccentric monks enlightened masters in Chan Buddhism sages in Chan Buddhism saints in Chan Buddhism song Dynasty
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The Impact of Contextual Teaching Method on Sichuan Folk Song Education and Students’Musical Expressiveness
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作者 Jing Li 《Journal of Contemporary Educational Research》 2024年第9期100-105,共6页
This study explores the application of the contextual teaching method in Sichuan folk song education and its impact on students’musical expressiveness.By incorporating contextual teaching methods in music classes,thi... This study explores the application of the contextual teaching method in Sichuan folk song education and its impact on students’musical expressiveness.By incorporating contextual teaching methods in music classes,this research investigates the effectiveness of this approach in enhancing students’understanding of Sichuan folk songs and improving their musical expressiveness and emotional expression.A mixed-method research approach is employed,utilizing classroom observations,questionnaires,interviews,and statistical analysis to assess the practical outcomes of contextual teaching in folk song education. 展开更多
关键词 Contextual teaching Sichuan folk songs Musical expressiveness Music education
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Effects of Pruning Types on Tree Vigor of Bamboo-Leaf Oak Inferred from Allometric Analysis
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作者 Hideyasu Shimada 《American Journal of Plant Sciences》 2023年第12期1430-1438,共9页
There are two well-known types of tree pruning, crown raising and crown reduction. In Japan, the former has been rarely used, whereas the latter has been widely used. However, it remains unclear which type is more eff... There are two well-known types of tree pruning, crown raising and crown reduction. In Japan, the former has been rarely used, whereas the latter has been widely used. However, it remains unclear which type is more effective to maintain tree vigor and health. Bamboo-leaf oak (Quercus myrsinifolia) trees were experimentally planted and pruned with the two pruning types compared with the no-pruning type. In the crown raising, the lower part of each tree was pruned, and its dominant leader was maintained from the aspect of structural pruning, whereas in the crown reduction, the upper part of each tree was pruned, and the tree height was reduced. The oak trees were observed and recorded in terms of leaf area, leaf weight, branch weight, and tree shape for about one year. The morphological data were statistically analyzed in terms of their allometric relationships. The crown raising type shared the same allometric patterns with the no-pruning types, but the crown reduction type did not. The trees of the crown reduction type were more likely to suffer from pests and disease. The allometric differences between the two pruning types may be considered the result of a decline in whole-tree vigor and health in crown reduction. The crown raising seemed more likely to control tree vigor and health than the crown reduction. The present results would help arborists determine which method to use for pruning. 展开更多
关键词 Allometric Difference Crown Raising Crown Reduction oak Tree Growth
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Aspect Level Songs Rating Based Upon Reviews in English
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作者 Muhammad Aasim Qureshi Muhammad Asif +4 位作者 Saira Anwar Umar Shaukat Atta-ur-Rahman Muhammad Adnan Khan Amir Mosavi 《Computers, Materials & Continua》 SCIE EI 2023年第2期2589-2605,共17页
With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after ... With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after the use of the item.The enormous increase in these reviews has raised the need for an automated system to analyze these reviews to rate these items.Sentiment Analysis(SA)is a technique that performs such decision analysis.This research targets the ranking and rating through sentiment analysis of these reviews,on different aspects.As a case study,Songs are opted to design and test the decision model.Different aspects of songs namely music,lyrics,song,voice and video are picked.For the reason,reviews of 20 songs are scraped from YouTube,pre-processed and formed a dataset.Different machine learning algorithms—Naïve Bayes(NB),Gradient Boost Tree,Logistic Regression LR,K-Nearest Neighbors(KNN)and Artificial Neural Network(ANN)are applied.ANN performed the best with 74.99%accuracy.Results are validated using K-Fold. 展开更多
关键词 Machine learning natural language processing songs reviews:sentiment analysis songs rating aspect level sentiment analysis reviews analysis text classification MUSIC
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Local and range-wide distribution of song types suggest Ovenbirds(Seiurus aurocapilla)have song neighborhoods but not macro-dialects
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作者 Patrick M.Jagielski Jennifer R.Foote 《Avian Research》 SCIE CSCD 2023年第2期191-199,共9页
The song systems of oscine passerines(songbirds)are complex and diverse.Because songs are used for both mate attraction and territory defense and are therefore important signals for survival and reproduction,comprehen... The song systems of oscine passerines(songbirds)are complex and diverse.Because songs are used for both mate attraction and territory defense and are therefore important signals for survival and reproduction,comprehensive knowledge of within and among species song structure and distribution is informative for understanding the evolution of song repertoires and vocal behaviour.In this study,we explored variation in the song structure of the Ovenbird(Seiurus aurocapilla),a widespread warbler(Family Parulidae)found in North American forests.We analyzed recordings from the 2021 breeding season to assess song type variation at a local(n=158 birds;Sault Ste.Marie,ON)and breeding range scale(n=512 birds;eBird).We characterized the local song types and tested whether Ovenbirds share song types with their neighbors more often than expected by chance.We then characterized song types of Ovenbirds across the breeding range to determine whether any geographic pattern of song clustering exists(i.e.,macro-dialects).We found 10 distinct song types and some evidence for song type clustering at the local study site(i.e.,song neighborhoods).We found 7 of those 10 song types throughout the breeding range and identified an additional 24 types that were not recorded in our local population.We found no evidence for song dialects across the Ovenbird breeding range.This study contributes to our understanding of Ovenbird song while simultaneously adding to our understanding of geographic structuring of warbler repertoires.Our work contributes to delineating a more comprehensive understanding of factors affecting dialect development for this diverse group of songbirds. 展开更多
关键词 DIALECTS eBird Geographic variation Ovenbird Parulidae Seiurus aurocapilla song type
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Forest composition and red oak (Quercus sp.) response to elevation gradients across greentree reservoirs
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作者 Cassandra Hug Pradip Saud +1 位作者 Keith McKnight Douglas C.Osborne 《Forest Ecosystems》 SCIE CSCD 2023年第5期607-617,共11页
Elevation gradients within forested wetlands have long been recognized for their role in defining species composition through factors such as hydrology and soil characteristics.Greentree reservoirs(GTRs)are leveeimpou... Elevation gradients within forested wetlands have long been recognized for their role in defining species composition through factors such as hydrology and soil characteristics.Greentree reservoirs(GTRs)are leveeimpounded tracts of bottomland hardwood forest flooded throughout the winter months to provide habitat for overwintering waterfowl.Artificial flooding of GTRs alters the forest composition due to flood frequency,depth,and duration in combination with slight changes in topography.To evaluate the effect of elevation gradients,soil properties,and management techniques in the overstory species composition and red oak(Quercus spp.)species abundance,we inventoried 662 plots across 12 independent GTRs in eastern Arkansas.In the lower elevations ranging from 50.98 to 54.99 m above sea level,the importance value index(IVI)was highest for nuttall oak(Quercus texana)and overcup oak(Quercus lyrata),whereas IVI shifted to cherrybark oak(Quercus pagoda)in the higher elevations ranging from 54.99 to 58.00 m.Alpha diversity did not differ by elevation gradient,soil property,or management technique within GTRs.Beta diversity,using non-metric multi-dimensional scaling(NMDS)analysis,indicated site-specific variability significantly correlated with the environmental predictors,including elevation(R^(2)=0.57),easting(R^(2)=0.47),soil texture(R^(2)=0.21),and pH(R^(2)=0.12).Red oak species-specific mixed-effects modeling of abundance response using Poisson distribution suggested an inverse correlation of nuttall oak and a direct correlation of cherrybark oak abundance with elevation.However,willow oak(Quercus phellos)abundance was not significantly affected by elevation but was by silt loam soil texture and restoration management techniques.These findings will aid management efforts to reduce the dominance of less desirable species that are prominent under specific environmental conditions and promote the dominance of more desirable species.Ultimately GTR sustainability is increasingly important amid the unpredictable impacts of climate change on the preferred red oak species that are economically,ecologically,and environmentally valuable to the sustaining economy of the local community and managing habitats for wildlife. 展开更多
关键词 Bottomland hardwoods DIVERSITY Forested wetland OVERSTORY Red oak Soil Thinning and management
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Assessment of Cork Oak Decline Using Digital Multispectral Imagery in Relation with in Situ Crown Condition
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作者 Soumia El Ahmadi Hassan Ramzi +2 位作者 Abderrahman Aafi Nejm Eddine Jmii Taoufik Aadel 《Open Journal of Forestry》 2023年第1期145-160,共16页
Cork oak in Maamora forest is experiencing the dieback phenomenon. The evaluation of the latter in this forest has gained the importance over time and with the solicitation of managers to objectify its phytosanitary s... Cork oak in Maamora forest is experiencing the dieback phenomenon. The evaluation of the latter in this forest has gained the importance over time and with the solicitation of managers to objectify its phytosanitary situation. Aiming at prioritizing management actions, remote sensing seems to be an effective tool to inquire about stands’ health conditions and their evolution. To this end, this study aims at mapping and validating health status of cork oak stands in Maamora. Sentinel 2 images in 2015 and 2020 were processed to calculate the differential normalized difference water index (NDWI), revealing vegetation moisture variation caused by drought. A statistical method based on thresholds was used to map cork oak dieback stands, those with no changes and those recovered. Results have shown that 54.63% of cork oak in Maamora forest have not changed in terms of phytosanitary situation between 2015 and 2020, 31.10% of oak stands are afflicted by a slight decline and 12.97% by a severe decline. Areas with slight or strong recovery remain minimal and represent 1.04% and 0.25% respectively. Ground data indicated that the map generated displayed a good distinction between stands severely and slightly declined with a global accuracy of 66.66%. Therefore, further research elaborating an advanced vegetation index reflecting the various factors of dieback would be of much importance. 展开更多
关键词 DIEBACK Cork oak Forest Mâamora Satellite Images Crown Condition
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Ice storm damage to oak forests in subtropical China
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作者 Jinyu Guo Jifa Cui +5 位作者 Nan Wu Yaqian Zhang Jie Wang Hanyu Xiang Baoshuang Hu Youbing Zhou 《Forest Ecosystems》 SCIE CSCD 2023年第3期368-377,共10页
Ice storms,as important sources of frequent and injurious disturbances,drive forest dynamics in the Northern Hemisphere.However,stand-level differential vulnerability to ice storms and the associated factors that pred... Ice storms,as important sources of frequent and injurious disturbances,drive forest dynamics in the Northern Hemisphere.However,stand-level differential vulnerability to ice storms and the associated factors that predispose forest stands remain unclear.This is particularly concerning in the subtropics where the frequency of ice storms is predicted to increase with global warming.Here we assessed how the impact on three forest stands(early and late secondary-growth forests,and old-growth forests)differed after an extreme ice storm during 20–21 March 2022,and identified the abiotic and biotic factors that determine the damage intensity in the Shennongjia World Natural Heritage Site,a biodiversity conservation hotspot in central China.We found a stand-specific‘middomain effect’where the late secondary-growth forest sustained the most severe damage,the early secondarygrowth forest sustained the least,and the old-growth forest suffered an intermediate amount.‘Crown broken’was the most severe damage type across all three forest stands,although the proportion of‘branch broken’was also high in the old-growth forest.Topography played a significant role in determining the vulnerability of the early secondary-growth forest to severe ice storms whereas the forest structure and composition were important factors in explaining the damage rates in the old-growth forest,although they differed among the damage categories.In contrast,topography,forest structure and composition generally explain the intensity of damage in the late secondary-growth forests.Our results highlight that,in subtropical forests,the intensity of damage caused by severe ice storms and related determining factors are stand-level dependent.We also suggest exploring potential management strategies(e.g.,slow-growing hardwood species that can resist storms should be the main species for reforestation in early secondary-growth forests)to mitigate the risk of future severe ice storms,as well as other wind-related climatic extremes. 展开更多
关键词 Ice storm Forest stand Extreme climate Forest vulnerability Abiotic and biotic factors oak forest
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Do forest health threats affect upland oak regeneration and recruitment?Advance reproduction is a key co-morbidity
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作者 Lance A.Vickers Benjamin O.Knapp +1 位作者 Daniel C.Dey Lauren S.Pile Knapp 《Forest Ecosystems》 SCIE CSCD 2023年第6期743-751,共9页
We analyzed national forest inventory data collected from circa 2000–2018 across 37 states in the eastern United States to better understand the influence of forest health related canopy disturbances on the regenerat... We analyzed national forest inventory data collected from circa 2000–2018 across 37 states in the eastern United States to better understand the influence of forest health related canopy disturbances on the regeneration and recruitment dynamics of upland oaks(Quercus).We found low levels of oak recruitment across all disturbance types examined but limited evidence of any direct effects from the type of disturbance on the population of regenerating oaks.The general lack of differences in oak regeneration response between forest health disturbances and disturbances caused by harvested or non-disturbed plots does not indicate that the effects of forest health disturbances were benign,however.Instead,low level of oak recruitment across all disturbance types highlights the pervasiveness of the trend of shifting composition in once oak-dominated forests where oak is absent or sparse in the regeneration layer.Our results show that oak recruitment was higher when oak was present as advance reproduction prior to disturbance from any cause examined.Collectively,these results lead us to conclude that the widespread inadequacy of oak advance reproduction in mature oak-dominated forests is the prevailing threat to oak forest health and sustainability.We suggest the status of advance reproduction be treated as a co-morbidity when weighing the risk and potential outcomes from other threats to upland oak forests in the eastern United States. 展开更多
关键词 Temperate deciduous forest Regeneration ecology Forest inventory and analysis oak/hickory Forest pests INSECT Disease Harvesting
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Impact of black cherry on pedunculate oak vitality in mixed forests:Balancing benefits and concerns
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作者 Ellen Desie Bart Muys +8 位作者 Jan den Ouden Bart Nyssen Rita Sousa-Silva Leon van den Berg Arnold van den Burg Gert-Jan van Duinen Koenraad Van Meerbeek Maaike Weijters Karen Vancampenhout 《Forest Ecosystems》 SCIE CSCD 2023年第6期690-699,共10页
The vitality of European forests continues to decline due to new pests and diseases,climate-change related disturbances and high loads of atmospheric nitrogen deposition.Deteriorating soil health is a major factor und... The vitality of European forests continues to decline due to new pests and diseases,climate-change related disturbances and high loads of atmospheric nitrogen deposition.Deteriorating soil health is a major factor underpinning the low vitality of West-European forests.Selecting tree species with soil ameliorative traits is proposed as an avenue to counteract soil acidification and improve overall forest vitality.Here we evaluate the impact of black cherry(Prunus serotina Ehrh.),a known rich litter species,on the vitality of neighboring pedunculate oak(Quercus robur L.)in ten mixed forests on sand in Germany,Belgium and the Netherlands.We found that black cherry admixture increases foliar N and P to a surplus whereas it causes deficiencies in foliar Mg,thereby resulting in an overall negative effect on oak foliar nutrient concentrations.Contrary,defoliation of oak leaves by herbivory decreases with the proximity of black cherry.Using structural equation modelling(SEM),we tested the hypothesized‘improved soil health’pathway.Our analyses showed that black cherry admixture leads to lower accumulation in the humus layer,resulting in higher soil base saturation which has a positive effect on foliar Ca yet a negative effect on total chlorophyll.Moreover,the SEM illustrated that herbivory of oak leaves decreases when black cherry is admixed,both via dilution and improved soil health.Indirect effects of black cherry on oak vitality via“improved soil health”in our SEM are however small in comparison to direct relations.Hence,our study showed that the combined positive and negative impacts of black cherry on oak vitality are limited,which tempers the potential benefits of using the rich litter species to counteract oak decline via improved soil health–yet,the concern of black cherry as an invasive alien species negatively affecting the vitality of mature pedunculate oak trees may also be exaggerated. 展开更多
关键词 Rich litter species Black cherry Nutrient cycling Insect herbivory Dilution effect Humus type Pedunculate oak Plant-soil interaction
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Heterogeneity in song rates in the Collared Flycatcher(Ficedula albicollis)explained with the availability parameter in generalized N-mixture models:Its importance for abundance estimates in avian aural counts
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作者 Grzegorz Neubauer Arkadiusz Sikora 《Avian Research》 SCIE CSCD 2023年第1期38-44,共7页
Binomial N-mixture models are commonly applied to estimate abundance unaffected by imperfect detection,but are known to be sensitive to violations of assumptions.One of the model’s assumptions,the independence of det... Binomial N-mixture models are commonly applied to estimate abundance unaffected by imperfect detection,but are known to be sensitive to violations of assumptions.One of the model’s assumptions,the independence of detections has rarely been tested.It requires that during a survey,detection of one individual does not affect detection of another individual.This assumption can be frequently violated in passerine birds,which exhibit territorial behaviour by singing,since neighbouring individuals are likely to motivate each other to vocalize,leading to non-independence in singing activity and in the following detection rate.Here,we explored this phenomenon with the generalized,binomial version of the N-mixture model,where detection probability is decomposed into availability probability φ-which can be interpreted as per capita song rate or the probability of vocalising-and actual detection probability p,given vocalisations take place.Using repeated counts of the Collared Flycatcher(Ficedula albicollis)as a case study,and treating the maximum observed counts C_(maxi) at a site i as an explanatory covariate for φ,we showed that per capita song rates increased with observed counts at a site.Hence,if song rates vary due to local abundance,including C_(maxi)as an explanatory variable for song rate addressed with φ,helps to explain this variation(which otherwise goes undetected)and improves inferences under the model.This had strong effects on the resulting abundance estimates:if this relationship was ignored in the models,total estimated population sizes were consequently lower by as much as 22-27%,compared to when this effect was included.Since it is likely that song rates may commonly be density-dependent in birds manifesting territorial behaviours by singing,further tests addressing violations of independence assumptions in these models are needed.As suggested by Kery and Royle(2016),despite some form of circularity likely being involved,modelling heterogeneity in the detection process with the help of C_(maxi)in standard N-mixture models(which,given availability,conflate availability with detection in a single parameter)should be applicable as well. 展开更多
关键词 ABUNDANCE Awailabity Bird∞mt Dansity dpendent detection Ganerlizd N minture models Singing sactiwity song Tate
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Reacting to Epidemics:The Innovative Imperial Public Health System during the Late Northern Song Dynasty
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作者 Asaf Goldschmidt 《Chinese Medicine and Culture》 2023年第1期68-75,共8页
Song China was a period in which China experienced a great increase in its population.Concurrently,the Song dynasty also experienced a rise in the frequency of epidemics and two major wars with the Western Xia and Lia... Song China was a period in which China experienced a great increase in its population.Concurrently,the Song dynasty also experienced a rise in the frequency of epidemics and two major wars with the Western Xia and Liao dynasties during the 1000s and 1040s.The consequences of these changes were exacerbated by the increased geographical mobility of certain social groups such as traders and examinees attending civil service examinations.Thus,casualties of wars,epidemics,or disease,especially of people whose families were far away and could not care for them were left without care and“their corpses often lay bare along the roads.”This new social environment created a need for general relief.The Northern Song government(960-1127 CE),especially during the reign of Emperor Huizong,established an innovative public health system to address this issue.The public health system included poorhouses,public hospitals,and pauper’s cemeteries.The first were more of charity organizations,whereas the latter two promoted public health by providing medical services for the poor and burial for those that nobody cared for.In terms of rationale behind these institutions,on the one hand,they constituted an attempt to get the poor and homeless off the streets while providing them relief or burial.On the other hand,it seems that Huizong’s deep concern with medicine propelled him to design and implement a comprehensive public health system oriented to prevent contagion and outbreak of epidemics.This article depicts the background,the organization,and the functions of the system.The article also discusses the conditions and reasons that gave rise to such a unique undertaking by the Northern Song government. 展开更多
关键词 EPIDEMICS History of medicine Hospitals HUIZONG Public health Pauper’s cemetery song dynasty
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Cultural Duplicity:The Social Poetic Nature of Folk Songs and Their Discourse
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作者 LU Fangfang 《Cultural and Religious Studies》 2023年第3期118-122,共5页
There is a close relationship between the folk songs and the earth bound society in China,bearing functions of load transfer,expression,dissemination of information,and beauty aspiration,etc.Folk songs are mainly pres... There is a close relationship between the folk songs and the earth bound society in China,bearing functions of load transfer,expression,dissemination of information,and beauty aspiration,etc.Folk songs are mainly presented through voice and thus possess powerful cultural duplicity,which rightly represents the social poetic quality that both the local residents and the nation-state need to take advantage of.A flexible space of co-existence is thus provided with for both of them. 展开更多
关键词 folk songs duplicity ethnic minority NATION-STATE
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Implications of Planting Southern Live Oak Trees in the Wrong Urban Space in East Baton Rouge, Louisiana United States
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作者 Lucinda A. Kangwana Yaw A. Twumasi +4 位作者 Zhu H. Ning Ronald O. Okwemba Janeth E. Mjema Priscilla M. Loh John Bosco Namwamba 《Open Journal of Forestry》 2023年第4期339-352,共14页
Afforestation has been observed as a green trend in urban areas. The incorporation of trees in urban infrastructure is highly recommended to act as a solution to outlined environmental problems such as global warming.... Afforestation has been observed as a green trend in urban areas. The incorporation of trees in urban infrastructure is highly recommended to act as a solution to outlined environmental problems such as global warming. However, it has been precipitously introduced in cities, towns, and metropolitans. The introduction of the green practice was so abrupt that it became devoid to meeting the essential needs for tree growth, thus, failing to bring out the desired effects. Inappropriately selecting and planting trees in urban spaces has resulted in stressed trees that are deficient at reaching up to the calculated goals and in the long run end up being problematic. The main objective of this study is to evaluate the implications of planting southern live oak (Quercus virginiana) trees in the wrong urban space so as to aid in recommending sustainable green solutions for the urban community. By studying southern live oaks planted in Howell Community Park and three randomly selected areas in Southern University Baton Rouge Campus, this study analyzes how the selection of these tree species in the urban spaces influenced their growth and general well-being. These urban spaces were randomly drafted based on accessibility and availability of several southern live oaks. Planting approaches in the four study areas were explored and the general health condition of the trees was determined using the tree appraisal method presented by the i-tree model: my tree. ArcGIS collector was used to collect the GPS coordinates of the trees and ArcMap was used to generate the maps of the study areas. ArcMap software geolocated the coordinates of the southern live oaks in all the four-study areas. The software was used to generate shapefiles of the four study areas and their location in East Baton Rouge. The analysis of the results proved that none of the southern live oaks had an excellent health condition and most of the trees experienced different issues due to planting them in the wrong urban spaces. 展开更多
关键词 Southern Live oak Tree Species Urban Space Wrong Urban Space
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