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Effect of natural and anthropogenic acidifi cation on aluminium distribution in forest soils of two regions in the Czech Republic 被引量:1
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作者 Lenka Pavlů LubošBorůvka +1 位作者 Ondřej Drábek Antonín Nikodem 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期363-370,共8页
To elucidate the dynamics of aluminium(Al),an element potentially toxic and strongly aff ected by acidifi cation processes,in soils,we selected two regions that were similar in relief,soil types,and vegetation cover b... To elucidate the dynamics of aluminium(Al),an element potentially toxic and strongly aff ected by acidifi cation processes,in soils,we selected two regions that were similar in relief,soil types,and vegetation cover but diff ered markedly in their history of acid precipitation:the JizerskéMountains(anthropogenically acidifi ed)and the NovohradskéMountains(naturally acidifi ed)in the Czech Republic.The levels of Al forms(exchangeable and organically bound)associated with diff erent environmental impacts were measured and univalent,divalent and trivalent Al species were quantifi ed using HPLC/IC.Exchangeable and organically bound Al concentrations were higher in the anthropogenically acidifi ed area.Only the concentrations of the leastdangerous species,the univalent,in organic soil horizons were similar for both mountains.The concentrations of exchangeable Al forms were correlated with Ca concentrations and with pH in the organic horizon.The known relationship of Al with soil pH was stronger in the mineral horizons.Relationships of exchangeable Al forms concentrations with sulphur concentrations or even more with the sulphur calcium molar ratio were found only in the JizerskéMountains,not in the Novohradské.Generally,the obtained results support the hypothesis that mechanisms diff ered between natural and anthropogenic acidifi cation. 展开更多
关键词 Soil acidifi cation Spruce forest Soil properties Aluminium forms Aluminium species
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The effect of climate factors on the size of forest wildfires(case study:Prague-East district,Czech Republic)
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作者 Zohreh Mohammadi Peter Lohmander +3 位作者 Jan Kašpar Roman Berčák Jaroslav Holuša Robert Marušák 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1291-1300,共10页
This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest wildfires.Multiple linear regression was used in combination with nonlinear variable transfo... This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest wildfires.Multiple linear regression was used in combination with nonlinear variable transformations to determine relevant nonlinear forest wildfire size functions.Data from the Prague-East District of the Czech Republic was used for model derivation.Individual burned forest area was hypothesized as a function of water vapor pressure,air temperature and wind speed.Wind speed was added to enhance predictions of the size of forest wildfires,and further improvements to the utility of prediction methods were added to the regression equation.The results show that if the air temperature increases,it may contain less water and the fuel will become drier.The size of the burned area then increases.If the relative humidity in the air increases and the wind speed decreases,the size of the burned area is reduced.Our model suggests that changes in the climate factors caused by ongoing climate change could cause significant changes in the size of wildfire in forests. 展开更多
关键词 Climatic variables Burned forest area Climate change Multiple linear regression
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Application of Restoration Methods on Brown Coal Localities of Czech Republic
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作者 M. Rehor M. Hendrychova M. Salek 《Journal of Agricultural Science and Technology(B)》 2011年第4期573-578,共6页
Over 70% brown coal reserves have been exploited in the North Bohemian Basin today. Openeast mining of brown coal naturally led to large landscape damages, Therefore reclamation work has acquired a great significance.... Over 70% brown coal reserves have been exploited in the North Bohemian Basin today. Openeast mining of brown coal naturally led to large landscape damages, Therefore reclamation work has acquired a great significance. The research methodology of the areas of interests and the reclamation works themselves described in this article arises from North Bohemian Mines locality reclamation philosophy. Apart from the earlier published methodology of fertilizable soils application used today in operation, experiments with filling areas left for natural succession and pilot have been launched lately. The results are stated in the paper. application of power plant stabilizer and ash in phyto-toxic areas 展开更多
关键词 RESTORATION DUMP GEOLOGY methodology.
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Deadwood position matters:Diversity and biomass of saproxylic beetles in a temperate beech forest
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作者 Vaclav Zumr Oto Nakladal +1 位作者 Josef Gallo JiríRemes 《Forest Ecosystems》 SCIE CSCD 2024年第1期120-130,共11页
Deadwood plays a key role for biodiversity in forests.A significant number of beetles from this group are currently listed as endangered in the Red List.In addition to other management recommendations,there have been ... Deadwood plays a key role for biodiversity in forests.A significant number of beetles from this group are currently listed as endangered in the Red List.In addition to other management recommendations,there have been recent efforts to enrich stands with dead wood to promote biodiversity.An important parameter for forestry enterprises is the optimization of these interventions.The study investigated the abundance,species richness,gamma diversity,conservation value and biomass of saproxylic beetles in natural forests using window traps.A total of 89traps were used for saproxylic beetle monitoring,of which 29 were placed on lying logs,30 on snags and 30 as controls in forest stand space.A total of 35,011 beetles were recorded in 564 species(61 families).Notably,20,515 of these belong to saproxylic beetles(59%)in 311 species(55%),with 62 classified as Red-List species(20%).In the group of'all saproxylic beetles',the results indicate that a diversity and y diversity(q=0)remain consistent across various deadwood types,whileβdiversity showed significant differences.Significant differences were found in the Red-List species group,where a diversity and y diversity differed,with higher values observed in snags.Rarefaction based total species richness of site was estimated to be 391 species,including 74 Red-Listed species.Comparing the sample coverage of the studied stand categories showed that all saproxylic species exhibit a pronounced preference for inhabiting areas featuring lying logs.Conversely,Red-List species mainly inhabit snags,withβdiversity being more similar to snags and forest stand space.Notably,both the conservation value(weighted average by conservation status)and beetle biomass are significantly highest in snags,whereas stand space shows the lowest values across all measured saproxylic beetle indices.Furthermore,the use of traps set on the poles in forest stand space resulted in an underestimation of the actual stand richness by 20%-25%.Our results support the conclusion that snags are indispensable features in beech forests,playing a key role in promoting high species diversity,especially among Red-List species,and supporting the biomass of saproxylic beetles.Consequently,it becomes crucial to incorporate a higher percentage of standing deadwood in managed forests or actively create equivalent environments by introducing high stumps. 展开更多
关键词 SNAGS COLEOPTERA Fagus sylvatica Unmanaged forests Red-list Coarse woody debris
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Instance Segmentation of Characters Recognized in Palmyrene Aramaic Inscriptions
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作者 Adéla Hamplová Alexey Lyavdansky +3 位作者 TomášNovák Ondrej Svojše David Franc Arnošt Veselý 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2869-2889,共21页
This study presents a single-class and multi-class instance segmentation approach applied to ancient Palmyrene inscriptions,employing two state-of-the-art deep learning algorithms,namely YOLOv8 and Roboflow 3.0.The go... This study presents a single-class and multi-class instance segmentation approach applied to ancient Palmyrene inscriptions,employing two state-of-the-art deep learning algorithms,namely YOLOv8 and Roboflow 3.0.The goal is to contribute to the preservation and understanding of historical texts,showcasing the potential of modern deep learning methods in archaeological research.Our research culminates in several key findings and scientific contributions.We comprehensively compare the performance of YOLOv8 and Roboflow 3.0 in the context of Palmyrene character segmentation—this comparative analysis mainly focuses on the strengths and weaknesses of each algorithm in this context.We also created and annotated an extensive dataset of Palmyrene inscriptions,a crucial resource for further research in the field.The dataset serves for training and evaluating the segmentation models.We employ comparative evaluation metrics to quantitatively assess the segmentation results,ensuring the reliability and reproducibility of our findings and we present custom visualization tools for predicted segmentation masks.Our study advances the state of the art in semi-automatic reading of Palmyrene inscriptions and establishes a benchmark for future research.The availability of the Palmyrene dataset and the insights into algorithm performance contribute to the broader understanding of historical text analysis. 展开更多
关键词 Optical character recognition instance segmentation Palmyrene ancient languages computer vision
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Genomic signatures of selection,local adaptation and production type characterisation of East Adriatic sheep breeds
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作者 Boris Lukic Ino Curik +4 位作者 Ivana Drzaic Vlatko Galić Mario Shihabi LubošVostry Vlatka Cubric-Curik 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期546-562,共17页
Background The importance of sheep breeding in the Mediterranean part of the eastern Adriatic has a long tradition since its arrival during the Neolithic migrations.Sheep production system is extensive and generally c... Background The importance of sheep breeding in the Mediterranean part of the eastern Adriatic has a long tradition since its arrival during the Neolithic migrations.Sheep production system is extensive and generally carried out in traditional systems without intensive systematic breeding programmes for high uniform trait production(carcass,wool and milk yield).Therefore,eight indigenous Croatian sheep breeds from eastern Adriatic treated here as metapopulation(EAS),are generally considered as multipurpose breeds(milk,meat and wool),not specialised for a particular type of production,but known for their robustness and resistance to certain environmental conditions.Our objective was to identify genomic regions and genes that exhibit patterns of positive selection signatures,decipher their biological and productive functionality,and provide a"genomic"characterization of EAS adaptation and determine its production type.Results We identified positive selection signatures in EAS using several methods based on reduced local variation,linkage disequilibrium and site frequency spectrum(eROHi,iHS,nSL and CLR).Our analyses identified numerous genomic regions and genes(e.g.,desmosomal cadherin and desmoglein gene families)associated with environmental adaptation and economically important traits.Most candidate genes were related to meat/production and health/immune response traits,while some of the candidate genes discovered were important for domestication and evolutionary processes(e.g.,HOXa gene family and FSIP2).These results were also confirmed by GO and QTL enrichment analysis.Conclusions Our results contribute to a better understanding of the unique adaptive genetic architecture of EAS and define its productive type,ultimately providing a new opportunity for future breeding programmes.At the same time,the numerous genes identified will improve our understanding of ruminant(sheep)robustness and resistance in the harsh and specific Mediterranean environment. 展开更多
关键词 Composite-likelihood ratio East Adriatic sheep Extreme ROH islands Genomic selection signatures Integrated haplotype score Number of segregating sites by length
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Assessing the effect of invasive organisms on forests under information uncertainty: The case of pine wood nematode in continental Europe
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作者 Nick Schafstall Laura Dobor +4 位作者 Marco Baldo Andrew MLiebhold Werner Rammer Juha Honkaniemi Tomás Hlásny 《Forest Ecosystems》 SCIE CSCD 2024年第5期685-696,共12页
Forests worldwide are experiencing increasingly intense biotic disturbances;however,assessing impacts of these disturbances is challenging due to the diverse range of organisms involved and the complex interactions am... Forests worldwide are experiencing increasingly intense biotic disturbances;however,assessing impacts of these disturbances is challenging due to the diverse range of organisms involved and the complex interactions among them.This particularly applies to invasive species,which can greatly alter ecological processes in their invaded territories.Here we focus on the pine wood nematode(PWN,Bursaphelenchus xylophilus),an invasive pathogen that has caused extensive mortality of pines in East Asia and more recently has invaded southern Europe.It is expected to expand its range into continental Europe with heavy impacts possible.Given the unknown dynamics of PWN in continental Europe,we reviewed laboratory and field experiments conducted in Asia and southern Europe to parameterize the main components of PWN biology and host-pathogen interactions in the Biotic Disturbance Engine(BITE),a model designed to implement a variety of forest biotic agents,from fungi to large herbivores.To simulate dynamically changing host availability and conditions,BITE was coupled with the forest landscape model iLand.The potential impacts of introducing PWN were assessed in a Central European forest landscape(40,928ha),likely within PWN’s reach in future decades.A parameter sensitivity analysis indicated a substantial influence of factors related to dispersal,colonization,and vegetation impact,whereas parameters related to population growth manifested a minor effect.Selection of different assumptions about biological processes resulted in differential timing and size of the main mortality wave,eliminating 40%–95%of pine trees within 100 years post-introduction,with a maximum annual carbon loss between 1.3%and 4.2%.PWN-induced tree mortality reduced the Gross Primary Productivity,increased heterotrophic respiration,and generated a distinct legacy sink effect in the recovery period.This assessment has corroborated the ecological plausibility of the simulated dynamics and highlighted the need for new strategies to navigate the substantial uncertainty in the agent’s biology and population dynamics. 展开更多
关键词 Biological invasions Process-based modelling Forest ecosystems Model parameters
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Changes in the adult sex ratio of six duck species breeding populations over two decades
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作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population Population dynamics Red-listed species WATERFOWL Winter weather conditions
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Differential roles of seed and sprout regeneration in forest diversity and productivity after disturbance
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作者 Marek Mejstrík Martin Svatek +2 位作者 Martina Pollastrini Martin Sramek Radim Matula 《Forest Ecosystems》 SCIE CSCD 2024年第3期371-380,共10页
Natural regeneration after disturbances is a key phase of forest development,which determines the trajectory of successional changes in tree species composition and diversity.Regenerating trees can originate from eith... Natural regeneration after disturbances is a key phase of forest development,which determines the trajectory of successional changes in tree species composition and diversity.Regenerating trees can originate from either seeds or sprouts produced by disturbed trees with sprouting ability.Although both regeneration strategies often develop and co-occur after a disturbance,they tend to affect forest development differently due to significant functional differences.However,the origin of tree regeneration is rarely distinguished in post-disturbance forest surveys and ecological studies,and the differential roles of seed and sprout regeneration in forest productivity and diversity remain poorly understood.To address these research gaps,we explored the role of sprout and seed regeneration in the formation of woody species diversity and above-ground biomass(AGB)productivity in early-stage forest development.Data were collected in two experimental forest stands in the Czech Republic,where trees were cut with varying intensities with the density of residual(uncut)trees ranging from 0 to 275 trees per hectare.All trees were mapped and their sizes were measured before cutting and then,either as a stump with sprouts or a residual tree,remeasured 11 years later.In addition,all tree saplings were mapped and measured 11 years after logging,and their origin(sprout or seed)was identified.To assess abundances and productivity,we estimated AGB of all2,685 sprouting stumps of 19 woody species and 504 generative(i.e.,seed origin)individuals of 16 woody species,using allometric equations.Mixed-effects models were used to analyze the effects of each regeneration strategy on woody species diversity and the total AGB under varying densities of residual trees.Nonmetric multidimensional scaling was used to evaluate the effect of regeneration strategies on species composition.AGB and diversity of sprouts were significantly higher than those of seed regeneration.Sprouts formed on average97.1%of the total regeneration AGB in H ady and 98.6%in Sobe s ice.The average species richness of sprouts was4.7 in H ady and 2.2 in Sob e sice,while the species richness of seed regeneration averaged 2.1 and 1.1 in H ady and Sob e sice,respectively.Increasing density of residual trees reduced AGB and diversity of both sprouts and seed regeneration,but seed regeneration was affected to a greater extent.Residual trees had an especially strong inhibitory effect on the establishment of seed regeneration.Consequently,seed-originated saplings were nearly absent in plots with high residual tree density,and abundant sprouts accounted for most of the AGB and diversity.However,unlike sprouts whose species composition resembled that of the original stand,seed regeneration brought in new species,enriching the stand?s overall species pool and beta diversity.Our results demonstrated differential roles of sprout and seed regeneration in the early stage of forest succession.Sprout regeneration was the main source of woody AGB productivity as well as species diversity,and its importance increased with the increasing density of standing mature trees.The results indicate the crucial yet previously underestimated role of sprout regeneration in post-disturbance forest dynamics.They suggest that the presence of residual mature trees,whether retained after partial cutting or undisturbed,can substantially suppress seed regeneration while the role of sprout regeneration in early succession becomes more distinctly evident. 展开更多
关键词 RESPROUTING SEEDING Residual trees Tree diversity Above-ground biomass
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Sustaining forest biodiversity:Exploring the effect of long-term natural disturbance dynamics on contemporary lichen communities in primary forest ecosystems
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作者 Rhiannon Gloor Marek Svitok +11 位作者 Martin Mikolas Jenyk Hofmeister Josef Halda Pavel Janda Francesco Maria Sabatini Lucie Zemanova Arne Buechling Daniel Kozak Matej Ferencik Michal Frankovic Martin Dusatko Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期556-567,共12页
In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are ef... In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are effective forest quality bioindicators,as they are generally long-lived organisms supported by continuity of specific forest structures and their associated microclimatic features.However,how lichen communities respond to the effects of fluctuating historical disturbances remains unclear.Using a dendrochronological approach,this study investigates how natural disturbance dynamics indirectly influence various lichen community metrics in some of Europe's best-preserved primary mixed-beech forests.Mixed modelling revealed that natural historical disturbance processes have decades-long effects on forest structural attributes,which had both congruent and divergent impacts on lichen community richness and composition.Total species richness indirectly benefited from both historical and recent higher-severity disturbances via increased standing dead tree basal area and canopy openness respectively-likely through the presence of both pioneer and late-successional species associated with these conditions.Red-listed species richness showed a dependence on habitat continuity(old trees),and increased with disturbance-related structures(standing dead trees)whilst simultaneously benefiting from periods without severe disturbance events(old trees and reduced deadwood volume).However,if the disturbance occurred over a century in the past,no substantial effect on forest structure was detected.Therefore,while disturbance-mediated forest structures can promote overall richness,threatened species appear vulnerable to more severe disturbance events-a concern,as disturbances are predicted to intensify with climate change.Additionally,the high number of threatened species found reinforce the critical role of primary forest structural attributes for biodiversity maintenance.Hence,we recommend a landscape-scale conservation approach encompassing forest patches in different successional stages to support diverse lichen communities,and the consideration of long-term disturbance dynamics in forest conservation efforts,as they provide critical insights for safeguarding biodiversity in our changing world. 展开更多
关键词 Mixed-beech forests Species richness Old-growth forests Carpathian mountains Biodiversity conservation DENDROECOLOGY Fagus sylvatica
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Planetary Homeostasis of Reactive Nitrogen Through Anaerobic Ammonium Oxidation
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作者 Guibing Zhu Bangrui Lan +8 位作者 Shuci Liu Cameron M.Callbeck Shanyun Wang Liping Jiang Asheesh Kumar Yadav Jan Vymazal Mike S.M.Jetten Ganlin Zhang Yongguan Zhu 《Engineering》 SCIE EI CAS CSCD 2024年第7期175-183,共9页
The availability of nitrogen(N)is crucial for both the productivity of terrestrial and aquatic ecosystems globally.However,the overuse of artificial fertilizers and the energy required to fix nitrogen have pushed the ... The availability of nitrogen(N)is crucial for both the productivity of terrestrial and aquatic ecosystems globally.However,the overuse of artificial fertilizers and the energy required to fix nitrogen have pushed the global nitrogen cycle(N-cycle)past its safe operating limits,leading to severe nitrogen pollution and the production of significant amounts of greenhouse gas nitrous oxide(N2O).The anaerobic ammonium oxidation(anammox)mechanism can counteract the release of ammonium and N2O in many oxygenlimited situations,assisting in the restoration of the homeostasis of the Earth’s N biogeochemistry.In this work,we looked into the characteristics of the anammox hotspots’distribution across various types of ecosystems worldwide.Anammox hotspots are present at diverse oxic-anoxic interfaces in terrestrial systems,and they are most prevalent at the oxic-anoxic transition zone in aquatic ecosystems.Based on the discovery of an anammox hotspot capable of oxidizing ammonium anoxically into N2 without N2O by-product,we then designed an innovative concept and technical routes of nature-based anammox hotspot geoengineering for climate change,biodiversity loss,and efficient utilization of water resources.After 15 years of actual use,anammox hotspot geoengineering has proven to be effective in ensuring clean drinking water,regulating the climate,fostering plant and animal diversity,and enhancing longterm environmental quality.The sustainable biogeoengineering of anammox could be a workable natural remedy to resolve the conflicts between environmental pollution and food security connected to N management. 展开更多
关键词 Biogeochemical N-cycle Oxic-anoxic interface Nature-based solution Biogeoengineering Nitrogen sustainable development
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Tree structure and diversity shape the biomass of primary temperate mountain forests
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作者 Dheeraj Ralhan Ruffy Rodrigo +14 位作者 Heather Keith Annemiek Irene Stegehuis Jakob Pavlin Yumei Jiang Milos Rydval Juliana Nogueira Alexandre Fruleux Marek Svitok Martin Mikolas Daniel Kozak Martin Dusatko Pavel Janda Oleh Chaskovsky Catalin-Constantin Roibu Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期568-579,共12页
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ... Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future. 展开更多
关键词 Biodiversity indicators Biomass carbon stock Ecosystem functioning Forest composition Primary forest structure Tree size distribution
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Manipulation of spermatogonial stem cells in livestock species 被引量:7
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作者 Filipp Savvulidi Martin Ptacek +1 位作者 Karina Savvulidi Vargova Ludek Stadnik 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第4期833-850,共18页
We are entering an exciting epoch in livestock biotechnology during which the fundamental approaches(such as transgenesis, spermatozoa cryopreservation and artificial insemination) will be enhanced based on the modern... We are entering an exciting epoch in livestock biotechnology during which the fundamental approaches(such as transgenesis, spermatozoa cryopreservation and artificial insemination) will be enhanced based on the modern understanding of the biology of spermatogonial stem cells(SSCs) combined with the outstanding recent advances in genomic editing technologies and in vitro cell culture systems. The general aim of this review is to outline comprehensively the promising applications of SSC manipulation that could in the nearest future find practical application in livestock breeding. Here, we will focus on 1) the basics of mammalian SSC biology;2) the approaches for SSC isolation and purification;3) the available in vitro systems for the stable expansion of isolated SSCs;4) a discussion of how the manipulation of SSCs can accelerate livestock transgenesis;5) a thorough overview of the techniques of SSC transplantation in livestock species(including the preparation of recipients for SSC transplantation,the ultrasonographic-guided SSC transplantation technique in large farm animals, and the perspectives to improve further the SSC transplantation efficiency), and finally, 6) why SSC transplantation is valuable to extend the techniques of spermatozoa cryopreservation and/or artificial insemination. For situations where no reliable data have yet been obtained for a particular livestock species, we will rely on the data obtained from studies conducted in rodents because the knowledge gained from rodent research is translatable to livestock species to a great extent. On the other hand, we will draw special attention to situations where such translation is not possible. 展开更多
关键词 CRISPR/Cas9 Genome editing LIVESTOCK TRANSGENESIS Long-term culture systems Male GERMLINE STEM cells Recipient preparation Sertoli CELLS Spermatogonial STEM CELLS Ultrasonographic-guided CANNULATION
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Properties and Applications of Bamboo Fiber—A Current-State-of-the Art 被引量:6
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作者 Chen Chen Haitao Li +7 位作者 Assima Dauletbek Feng Shen David Hui Milan Gaff Rodolfo Lorenzo Ileana Corbi Ottavia Corbi Mahmud Ashraf 《Journal of Renewable Materials》 SCIE EI 2022年第3期605-624,共20页
Fibers are used in many forms in engineering applications–one of the most common being used as reinforcement.Due to its renewable short natural growth cycle and abundance of bamboo resources,bamboo fiber has attracte... Fibers are used in many forms in engineering applications–one of the most common being used as reinforcement.Due to its renewable short natural growth cycle and abundance of bamboo resources,bamboo fiber has attracted attention over other natural fibers.Bamboo fiber has a complex natural structure but offers excellent mechanical properties,which are utilized in the textile,papermaking,construction,and composites industry.However,bam-boo fibers can easily absorb moisture and are prone to corrosion limiting their use in engineering applications.Therefore,a better understanding of bamboo fiber is particularly important.This paper reviews all existing research on the mechanical characterization of bamboo fiber with an emphasis on the extraction and treatment techniques,and their effect on relevant properties.The chemical composition of bamboo fibers has also been thoroughly investigated and presented herein.Current applications and future opportunities for bamboo fibers in various fields have been presented with a focus on research needs.This work can serve as a reference for future research on bamboo fiber. 展开更多
关键词 Bamboo fiber chemical composition STRUCTURE production method PROPERTIES APPLICATION
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Epigenetic and non-epigenetic mode of SIRT1 action during oocyte meiosis progression 被引量:3
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作者 Jan Nevoral Lukas Landsmann +11 位作者 Miriam Stiavnicka Petr Hosek Jiri Moravec Sarka Prokesova Hedvika Rimnacova Eliska Koutna Pavel Klein Kristyna Hoskova Tereza Zalmanova Tereza Fenclova Jaroslav Petr Milena Kralickova 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第4期895-906,共12页
Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further... Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further fate of mature oocytes has been strongly suggested. We hypothesised that SIRT1 plays the role of a signalling molecule in mature oocytes through selected epigenetic and non-epigenetic regulation.Results: We observed SIRT1 re-localisation in mature oocytes and its association with spindle microtubules.In mature oocytes, SIRT1 distribution shows a spindle-like pattern, and spindle-specific SIRT1 action decreasesα-tubulin acetylation. Based on the observation of the histone code in immature and mature oocytes, we suggest that SIRT1 is mostly predestined for an epigenetic mode of action in the germinal vesicles(GVs) of immature oocytes. Accordingly, BML-278-driven trimethylation of lysine K9 in histone H3 in mature oocytes is considered to be a result of GV epigenetic transformation.Conclusions: Taken together, our observations point out the dual spatiotemporal SIRT1 action in oocytes,which can be readily switched from the epigenetic to non-epigenetic mode of action depending on the progress of meiosis. 展开更多
关键词 Epigenetics HISTONE code In vitro maturation OOCYTE SIRT1 SIRTUIN 1
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The diameter of beech snags is an important factor for saproxylic beetle richness: Implications for forest management and conservation 被引量:1
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作者 Václav Zumr Oto Nakládal +1 位作者 Lukás Bílek JiríRemes 《Forest Ecosystems》 SCIE CSCD 2023年第5期635-645,共11页
Snags are an important component of beech forests that promote biodiversity.However,their occurrence is completely marginal in managed stands.Creating snags in these stands would greatly enhance biodiversity.We invest... Snags are an important component of beech forests that promote biodiversity.However,their occurrence is completely marginal in managed stands.Creating snags in these stands would greatly enhance biodiversity.We investigated whether snag dimensions were important for saproxylic beetle richness since they were easily transferable parameters to forest management and assessed the presence of other snag microhabitats affecting beetle communities.Data collection was performed using passive flight traps placed on thirty snags in a recent beech reserve.A total of 6706 adults belonging to 231 saproxylic species(53 Red List species,23%)were captured.The results showed that the most important snag parameters were the diameter(thickness)and canopy openness of the surrounding stands.The occurrence of Fomes fomentarius,the volume of snag and decay class 3 were marginally significant in terms of the preference of all saproxylic species.Alpha diversity was reduced by an advanced degree of decay and a surprisingly deep stem cavity.After dividing snag thickness into categories(<35 cm;35–70 cm and>70 cm DBH),we found that categories with snag diameter greater than 35 cm showed little differences in all saproxylic and Red List species richness and diversity indices and exhibited the highest similarity in beetle communities.Regarding recommendations to forest managers in terms of optimization and simplification of practical procedures,we suggest actively creating high stumps to act as snags greater than 35 cm in DBH diameter to promote biodiversity in beech management stands. 展开更多
关键词 DEADWOOD Coleoptera Biodiversity Active management Endangered beetles
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Diversity of click beetles in managed nonnative coniferous and native beech stands: Consequences of changes in the structural and species composition of tree stands in Central Europe 被引量:1
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作者 Václav Zumr Oto Nakladal +2 位作者 JiríRemes Tereza Brestovanska Váaclav Zumr 《Forest Ecosystems》 SCIE CSCD 2022年第5期596-605,共10页
The natural composition of forests has undergone significant changes over recent centuries.A closer-to-natural tree species composition has long been perceived as key to a high biodiversity.We investigated the impact ... The natural composition of forests has undergone significant changes over recent centuries.A closer-to-natural tree species composition has long been perceived as key to a high biodiversity.We investigated the impact on communities of click beetles(Elateridae)caused by changes in the tree species composition of spruce monocultures compared to reference sites of recently unmanaged natural beech forests.To collect data,passive interception traps were distributed within managed spruce stands of different age classes and natural beech forests of various developmental stages.The beetle species richness was slightly but not significantly higher in the beech forests.The saproxylic species group was significantly more common in the spruce stands,whereas the group of nonsaproxylic species was significantly more abundant in the beech stands.In the commercial stands,the significantly highest species richness was in the clearings(0–10-year-old stands),and at this forest age class,the vast majority of the beetle species occurred in the spruce stands.In the developmental stages of the natural forest,a slightly higher beetle richness was found at the disintegration stage.The study results suggested that different tree species compositions and stand structures affect the communities of click beetles and substantially change their species composition and thus their response to external influences.Therefore,management of stands using diverse silvicultural systems is recommended for creating diverse ecological niches in forests. 展开更多
关键词 Species richness Forest management Saproxylic beetles Nonsaproxylic beetles Dead wood ELATERIDAE Canopy openness
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Effects of Creatine Monohydrate Diet on Muscle Metabolism,Quality,Sensory and Oxidative Stability of Pork in Female,Entire and Castrated Male Pigs 被引量:1
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作者 Ivan Bahelka Ondřej Bučko +2 位作者 Roman Stupka MichalŠprysl JaroslavČítek 《Journal of Agricultural Science and Technology(A)》 2020年第2期78-85,共8页
Forty-two (42) finishing pigs (entire males—EM, surgical castrates—SC and gilts—G, each of 14)—progeny of Landracesows and Hampshire × Pietrain boars, were included in the trial. They were randomly divided in... Forty-two (42) finishing pigs (entire males—EM, surgical castrates—SC and gilts—G, each of 14)—progeny of Landracesows and Hampshire × Pietrain boars, were included in the trial. They were randomly divided into control and experimental groups(each of seven). Control groups were fed the standard diet without any supplement. Experimental groups received standard diet withthe same composition as control but with supplement of creatine monohydrate (CMH, 2.0 g/kg of feed) for 30 d prior to slaughter.Sex of pigs had significant effect (p < 0.05) on drip loss and tenderness of pork when EM showed higher drip loss than SC and lowertenderness compared to other two groups (4.71% vs. 3.80%, resp. 3.23 vs. 3.91 and 4.12). Creatine level in plasma was increased byCMH supplementation in 46% in EM, 43% in SC and 41% in G. Similarly, concentration of phosphocreatine (PCr) in muscleincreased in 84% in EM, 88% in SC and 83% in G, respectively. CMH also improved meat colour L* (50.03 vs. 48.88) and reduceddrip loss in both EM (5.24% vs. 4.18%) and G (4.48% vs. 3.60%). Higher tenderness and better oxidative stability of pork after CMHsupplementation was found in all three sexes. 展开更多
关键词 Eating quality feed additives oxidative stability PIG pork quality
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SIRT1-dependent modulation of methylation and acetylation of histone H3 on lysine 9(H3K9)in the zygotic pronuclei improves porcine embryo development 被引量:1
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作者 Katerina Adamkova Young-Joo Yi +8 位作者 Jaroslav Petr Tereza Zalmanova Kristyna Hoskova Pavla Jelinkova Jiri Moravec Milena Kralickova Miriam Sutovsky Peter Sutovsky Jan Nevoral 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第2期339-350,共12页
Background: The histone code is an established epigenetic regulator of early embryonic development in mammals.The lysine residue K9 of histone H3(H3 K9) is a prime target of SIRT1, a member of NAD+-dependent histone d... Background: The histone code is an established epigenetic regulator of early embryonic development in mammals.The lysine residue K9 of histone H3(H3 K9) is a prime target of SIRT1, a member of NAD+-dependent histone deacetylase family of enzymes targeting both histone and non-histone substrates. At present, little is known about SIRT1-modulation of H3 K9 in zygotic pronuclei and its association with the success of preimplantation embryo development. Therefore, we evaluated the effect of SIRT1 activity on H3 K9 methylation and acetylation in porcine zygotes and the significance of H3 K9 modifications for early embryonic development.Results: Our results show that SIRT1 activators resveratrol and BML-278 increased H3 K9 methylation and suppressed H3 K9 acetylation in both the paternal and maternal pronucleus. Inversely, SIRT1 inhibitors nicotinamide and sirtinol suppressed methylation and increased acetylation of pronuclear H3 K9. Evaluation of early embryonic development confirmed positive effect of selective SIRT1 activation on blastocyst formation rate(5.2 ± 2.9% versus 32.9 ± 8.1% in vehicle control and BML-278 group, respectively; P ≤ 0.05). Stimulation of SIRT1 activity coincided with fluorometric signal intensity of ooplasmic ubiquitin ligase MDM2, a known substrate of SIRT1 and known limiting factor of epigenome remodeling.Conclusions: We conclude that SIRT1 modulates zygotic histone code, obviously through direct deacetylation and via non-histone targets resulting in increased H3 K9 me3. These changes in zygotes lead to more successful pre-implantation embryonic development and, indeed, the specific SIRT1 activation due to BML-278 is beneficial for in vitro embryo production and blastocyst achievement. 展开更多
关键词 Embryonic DEVELOPMENT Epigenetics H3K9 METHYLATION SIRT1 SIRTUIN
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Analyzing Land Cover Change—The Impact of the Motorway Construction and Their Operation on Landscape Structure 被引量:1
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作者 Zdenek Keken Marika Sebkova Jan Skalos 《Journal of Geographic Information System》 2014年第5期559-571,共13页
The aim of our study was to assess the influence of motorways on landscape structure changes. The research was situated on segments of the D1 and D3 motorways in the Czech Republic. The method used for determining the... The aim of our study was to assess the influence of motorways on landscape structure changes. The research was situated on segments of the D1 and D3 motorways in the Czech Republic. The method used for determining the impacts of the construction and operation of the motorway on the landscape structure was based on comparing the development of the land cover types in an area where the motorway was present for almost the entire monitored period (D1 motorway segment) with the development of the land cover types in an area where the motorway was constructed towards the end of the monitored period (D3 motorway segment). Monitored period?was?between years 1949, 1988 (1984 segment of motorway D3) and 2007. Source materials were processed and analyzed in the ArcGIS software environment. Our comparison indicated that the main differences between segments were in the level of development of commercial, industrial and agricultural built-up area in the vicinity of motorways. The existence of the motorway also contributed to the development of residential areas. It should be noted that in both cases there was also an increase in the extension?of shrubs and scattered vegetation, and in small quantities also category of forest. 展开更多
关键词 LAND Use Landscape Development AERIAL PHOTOS Commercial SUBURBANIZATION LAND OCCUPATION
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