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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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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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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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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 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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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
关键词 应用 恢复方法 褐煤 捷克 填海工程 波西米亚 工作原理 工程哲学
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Habitat-dependent breeding biology of the Blue Tit(Cyanistes caeruleus)across a continuous and heterogeneous Mediterranean woodland
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作者 Jorge Garrido-Bautista Carmen Hernandez-Ruiz +4 位作者 Jose Luis Ros-Santaella Eliana Pintus Nicola Bernardo Mar Comas Gregorio Moreno-Rueda 《Avian Research》 SCIE CSCD 2023年第3期499-510,共12页
Mediterranean woodland environments are characterised by high spatial and temporal heterogeneity,which means the inhabiting species face a wide variety of selective pressures.Species may respond differently to habitat... Mediterranean woodland environments are characterised by high spatial and temporal heterogeneity,which means the inhabiting species face a wide variety of selective pressures.Species may respond differently to habitat heterogeneity and so distinct eco-evolutionary scenarios may be responsible for the inter-habitat variability in reproductive strategies observed in certain species.The inter-forest variability of some reproductive traits in passerines has been examined by comparing forest patches or separated fragments.However,there is still little information regarding how such highly mobile animals adjust their breeding performance across continuous and heterogeneous woodlands.Here we studied the reproductive performance of a population of Blue Tits(Cyanistes caeruleus) in an area of continuous Mediterranean woodland that included two mountain slopes and four different types of forest,ranging from deciduous oak forests to perennial non-oak forests.We studied the habitat heterogeneity and inter-forest phenotypic variation in terms of reproductive performance and adult and nestling biometry,besides also exploring the effects of ectoparasites on Blue Tit reproduction.Eggs were laid earliest in deciduous Pyrenean Oak(Quercus pyrenaica) forests,while clutch size and the number of fledglings were highest in the humid Pyrenean Oak forest,which had the greatest tree coverage and most humid climate,and lowest in the coniferous Scots Pine(Pinus sylvestris) forest.There were no inter-forest differences in hatching(percentage of nests with at least one egg hatched) and fledging(percentage of nests in which at least one nestling fledged)success.Similarly,there were no inter-forest differences in adult and nestling biometry,but adults that raised more fledglings had a lower body mass,while males whose females laid larger clutches had smaller tarsi.Most ectoparasites did not affect Blue Tit reproduction,although Culicoides had a negative impact on nestling body mass.These results suggest that Blue Tits can adjust their reproductive effort to the forest where they breed even across a very small spatial scale.Different eco-evolutionary scenarios,such as phenotypic plasticity or genetic structuring and local adaptation,might explain the phenotypic differentiation in the reproductive strategies observed over small areas in woodlands. 展开更多
关键词 BIRDS Breeding success Cavity-nesting birds Paridae PASSERINES REPRODUCTION
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The Characteristics of Glued Tensile Shear Strength Constituted of Wood Cut by CO_(2) Laser
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作者 Fatemeh Rezaei Milan Gaff +10 位作者 Róbert Nemeth Jerzy Smardzewski Peter Niemz Haitao Li Anil Kumar Sethy Luigi Todaro Gourav Kamboj Sumanta Das Roberto Corleto Gianluca Ditommaso Miklós Bak 《Journal of Renewable Materials》 EI 2023年第8期3277-3296,共20页
The performance of engineered wood products is highly associated with proper bonding and an efficient cutting method.This paper investigates the influence of CO_(2) laser cutting on the wetting properties,the modified ch... The performance of engineered wood products is highly associated with proper bonding and an efficient cutting method.This paper investigates the influence of CO_(2) laser cutting on the wetting properties,the modified che-mical component of the laser-cut surface,and the strength and adhesive penetration near the bondline.Beech-wood is cut by the laser with varying processing parameters,cutting speeds,gas pressures,and focal point positions.The laser-cut samples were divided into two groups,sanded and non-sanded samples.Polyvinyl acetate adhesive(PVAc)was used to bond the groups of laser-cut samples.After assembly with cold pressing,the tensile shear test was carried out.Numerical modelling was carried out to determine the partial elongation and shear strain of the glue line.Based on this,the shear modulus and linear elasticity of the glue line were estimated.Scan-ning electron microscopy was used to assess the adhesive penetration into the porosity structure of the laser-cut samples,and the depth of the heat-affected zone.The laser-cut surface was analysed by Fourier transform infrared spectroscopy.The wetting properties of the laser-cut surface were investigated by using a contact angle goni-ometer.The numerical model of the strain-stress curve confirmed the experimental model.The highest modulus of the linear elasticity of the glue in the numerical calculation belongs to the joint containing laser-cut samples at a gas pressure of 21(bar).The penetration depth of PVAc adhesive into the porosity structure of the laser-cut sam-ples was similar to that of sawn samples.The deepest heat-affected zone in the laser-cut samples was 150µm.A PVAc drop disappeared immediately on the laser-cut surface without sanding,but gradually on the sanded surface.In contrast,the drop on the sawn surface remained with an angle of 32°–48°.The degradation of hemi-cellulose and lignin was proven by the lower intensity of the C=O and C-O Bonds,compared to the sawn surface. 展开更多
关键词 CO_(2)laser cutting speed focal point position gas pressure glued tensile shear strength
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Douglas-fi r(Pseudotsuga menziesii(Mirb.)Franco)in Europe:an overview of management practices
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作者 Valeriu-Norocel Nicolescu William LMason +17 位作者 Jean-Charles Bastien Torsten Vor Krasimira Petkova Vilém Podrázský Martina Đodan Sanja Perić Nicola La Porta Robert Brus Siniša Andrašev Martin Slávik Juraj Modranský Michal Pástor Károly Rédei Branislav Cvjetkovic Ahmet Sivacioğlu Vasyl Lavnyy Cornelia Buzatu-Goanță Gheorghe Mihăilescu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期871-888,共18页
Douglas-fir(Pseudotsuga menziesii(Mirb.)Franco),one of the most commercially important tree species in western North America and one of the most valuable timber trees worldwide,was introduced to Europe in 1827.It beca... Douglas-fir(Pseudotsuga menziesii(Mirb.)Franco),one of the most commercially important tree species in western North America and one of the most valuable timber trees worldwide,was introduced to Europe in 1827.It became a major species for aff orestation in Western Europe after WWII,currently grows in 35 countries on over 0.83 million ha and is one of the most widespread nonnative tree species across the continent.A lower sensitivity to drought makes Douglas-fi r a potential alternative to the more drought-sensitive Norway spruce so its importance in Europe is expected to increase in the future.It is one of the fastest growing conifer species cultivated in Europe,with the largest reported dimensions of 2.3 m in diameter and 67.5 m in height.Pure stands have high productivity(up to 20 m 3 ha−1 a−1)and production(over 1000 m 3 ha−1).The species is generally regenerated by planting(initial stocking density from less than 1000 seedlings ha−1 to more than 4000 ha−1),using seedlings of European provenance derived from seed orchards or certifi ed seed stands.As the range of end-uses of its wood is very wide,the rotation period of Douglas-fi r is highly variable and ranges between 40 and 120 years.When the production of large-sized,knotfree timber is targeted,thinnings are always coupled with pruning up to 6 m.There is an increasing interest in growing Douglas-fi r in mixtures and managing stands through close-to-nature silviculture,but the species’intermediate shade tolerance means that it is best managed through group selection or shelterwood systems. 展开更多
关键词 Douglas-fi r Ecological requirements Growth and yield Timber Climate change
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Exploring well-being disparities between urban and rural areas:A case study in the Stavropol Territory,Russia
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作者 Anastasia CHAPLITSKAYA Wim HEIJMAN Johan van OPHEM 《Regional Sustainability》 2024年第1期80-92,共13页
Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially importa... Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially important in countries where agricultural production accounts for a significant share of the gross product,such as Russia.In this study,we identified the key indicators of satisfaction and differences between rural and urban citizens based on their social,economic,and environmental backgrounds,and determined whether there are well-being disparities between rural and urban areas in the Stavropol Territory,Russia.We collected primary data through a survey based on the European Social Survey framework to investigate the potential differences between rural and urban areas.By computing the regional well-being index using principal component analysis,we found that there was no statistically significant difference in well-being between rural and urban areas.Results of key indicators showed that rural residents felt psychologically more comfortable and safer,assessed their family relationships better,and adhered more to traditions and customs.However,urban residents showed better economic and social conditions(e.g.,infrastructures,medical care,education,and Internet access).The results of this study imply that we can better understand the local needs,advantages,and unique qualities,thereby gaining insight into the effectiveness of government programs.Policy-makers and local authorities can consider targeted interventions based on the findings of this study and strive to enhance the well-being of both urban and rural residents. 展开更多
关键词 WELL-BEING Sustainable development Rural areas Urban areas Principal component analysis(PCA) RUSSIA
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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:4
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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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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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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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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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Can a dam type of an alpine lake be derived from lake geometry?A negative result
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作者 Adam EMMER Vojtěch CURIN 《Journal of Mountain Science》 SCIE CSCD 2021年第3期614-621,共8页
Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is apparent.As a consequence,numero... Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is apparent.As a consequence,numerous region-and nation-wide GLOF assessment studies have been published recently.These studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by them.Clearly,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual assignment.Different lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mechanism(dam overtopping/dam breach)and thus GLOF magnitude.In this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam type.Our dataset of 851 lakes of the Cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the spectra.The only promising results are obtained for extreme values(selected bins)of the ratios.For instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed lake.Overall,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra. 展开更多
关键词 Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed Negative result Cordillera Blanca
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Assessing the response of dryland barley yield to climate variability in semi-arid regions,Iran
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作者 Mohammad KHEIRI Jafar KAMBOUZIA +2 位作者 Reza DEIHIMFARD Saghi M MOGHADDAM Seyran ANVARI 《Journal of Arid Land》 SCIE CSCD 2021年第9期905-917,共13页
Precipitation and temperature are the most abiotic factors that greatly impact the yield of crop,particularly in dryland.Barley,as the main cereal is predominantly cultivated in dryland and the livelihood of smallhold... Precipitation and temperature are the most abiotic factors that greatly impact the yield of crop,particularly in dryland.Barley,as the main cereal is predominantly cultivated in dryland and the livelihood of smallholders depends on the production of this crop,particularly in arid and semi-arid regions.This study aimed to investigate the response of the grain yield of dryland barley to temperature and precipitation variations at annual,seasonal and monthly scales in seven counties of East and West Azerbaijan provinces in northwestern Iran during 1991-2010.Humidity index(HI)was calculated and its relationship with dryland barley yield was evaluated at annual and monthly scales.The results showed that the minimum,maximum and mean temperatures increased by 0.19℃/a,0.11℃/a and 0.10℃/a,respectively,while annual precipitation decreased by 0.80 mm/a during 1991-2010.Climate in study area has become drier by 0.22/a in annual HI during the study period.Negative effects of increasing temperature on the grain yield of dryland barley were more severe than the positive effects of increasing precipitation.Besides,weather variations in April and May were related more to the grain yield of dryland barley than those in other months.The grain yield of dryland barley was more drastically affected by the variation of annual minimum temperature comparing with other weather variables.Furthermore,our findings illustrated that the grain yield of dryland barley increased by 0.01 t/hm^(2) for each unit increase in annual HI during 1991-2010.Finally,any increase in the monthly HI led to crop yield improvement in the study area,particularly in the drier counties,i.e.,Myaneh,Tabriz and Khoy in Iran. 展开更多
关键词 humidity index crop yield spatiotemporal variation temperature precipitation
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The Extent of Land Use Impact on Water Regime in the Vseminka Catchment
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作者 Pavel Kovar Darina Vassova 《Journal of Environmental Science and Engineering(B)》 2012年第2期228-237,共10页
关键词 土地利用变化 影响程度 水情 降雨径流过程 地下水补给 流域 洪水事件 水量平衡分析
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Differences in Aggressiveness and Morphology of Mycosphaerella graminicola Isolates Causal Agent of Septoria Tritici Blotch on Wheat
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作者 L. Vechet E. Vydrova 《Journal of Agricultural Science and Technology(A)》 2011年第3X期386-393,共8页
关键词 小麦品种 形态特征 分离株 污点 覆盖面积 栽培类型 反应 平均
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