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Snow damages on trees of an uneven age in mixed broadleaf forests: effects of topographical conditions and tree characteristics
No full textSnow damage on natural stands is an important problem concerning mountainous forest management. In the present research, the frequency and intensity of heavy snow damage on natural stands and the relationship of damages with characteristics of trees, stand and topography were studied in mountainous forests of northern Iran. A systematic sampling design was applied to the study area (140 ha), with 122 circular plots. The grid dimension was 100 m and each plot area was 1000 m2. The four types of snow damage to trees include: crown damage (8.6%), stem breakage (5.4%), uprooting (3.2%), and bending (1.4%). The frequency of crown damage grew with an increase in the diameter at breast height (DBH), while the frequency of stem breakage, uprooting and bending decreased with an increase the DBH. The frequency of crown damage, stem breakage, and total damages was related to tree species (p < 0.01). Not all tree species were equally susceptible to snow damage. The amount of damage grew with increasing elevation and slope angle and decreased with increasing soil depth. Young trees (DBH < 25 cm) were more susceptible to snow damage than other trees. Snow damage decreased by as the trees in the stand became more mixed in age. The susceptibility of trees to snow damage increased by height and slenderness coefficient. With adequate silvicultural operation, snow damage can be reduced to a minimum level in these natural forests.6s
Design hydrograph estimation in small and ungauged basins: a comparative assessment of event based (EBA4SUB) and continuous (COSMO4SUB) modelling approaches
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LA MISSIONE BIOLOGICA SAGAN-OMO DI EDOARDO ZAVATTARI DEL MARZO-OTTOBRE 1939 I. PREPARAZIONE, SVOLGIMENTO, RELAZIONI E RENDICONTO (FINE 1938-DICEMBRE 1939)
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Reactive postural responses to continous yaw perturbation in healthy humans: The effect of aging
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Synthesis of Stilbene and Chalcone Inhibitors of Influenza A Virus by SBA-15 Supported Hoveyda-Grubbs Metathesis
No full textThe age dynamics of vineyards: past trends affecting the future
No full textThe paperintroducesamodified versionofthedemographicbalanceequationcommonlyusedinhumandemographyinthestudyof
populations ofpermanentcrops.TheproposedmethodologyisthenappliedtoanalyzingtheevolutionoftheItalianvineyard.
In short,thestudymeasuresdifferentfactorsthathavehadanimpactontheextensionoftheItalianvineyardandonitsagestructuresuchas
the reducedinvestmentsinnewplantations;themassiveearlyexplantandalsotheextendedlifeofthevineyardssincetheyarekeptinproduction
well beyondtheconventionallimitoftheireconomiclife.ResultsshowthatthereductionoftheareacultivatedwithgrapesinItalyisdueto
different reasons,someofwhichrelatetothepastwhileothersmirrormorerecentbehaviorsofvinegrowers.
The methodologyalsoallowsthepredictionoftendenciesinthefuture.Threescenariosarebuilt,basedondifferenthypothesisaboutnew
investments andexplantationratesthataccountforthewineEUCMO2013–2030. Projectionsshow,thatinthenextdecades,boththeextension
of cultivatedareaandplantagewillbedeeplyinfluenced bychoicesthathadbeenmadeevendecadesbefore.Comparingtheresultsobtained
under thedifferenthypothesis,helpstoassesstherangeofpossibleimpactsofthenewpolicyframework.
In anincreasinglyglobalandcompetitivemarket,theanalysisproposedprovidesoriginalinsightsonsomefuturewavesinthewineindustry
both topolicymakersandstakeholders.Thisawarenessisespeciallyneededinordertoputinplacestrategiesaimedatavoidingsupply-demand
mismatches inasectorwheresupplymovesslowlywhiledemandtrendsarefastandalmostunpredictable.3n
