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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Možnosti využití přirozené obnovy buku na revíru Ratibořice

Mervart, Tomáš January 2011 (has links)
No description available.
32

Komprimace dřeva buku obsahující nepravé jádro a porovnání s dřevem bělovým

Putna, Ondřej January 2012 (has links)
No description available.
33

Diverzita ektomykorhizních hub ve vybraných bučinách Blanského lesa / Diversity of ectomycorrhizal fungi in selected beech stands in Blanský les

HEJNA, Ondřej January 2013 (has links)
The diversity and abundance of ectomycorrhizal fungi in three beech stands were compared during 2012 and 2013 years in two soil horizons. Individual ectomycorrhizal roots tips were morphologically and anatomically characterized. Representative morphotypes were identified by using molecular methods to confirm and verify ectomycorrhizal fungal species.
34

Možnosti uplatnění obalů typu Marbet při pěstování sadebního materiálu buku lesního

Čeřovský, Jindřich January 2012 (has links)
No description available.
35

Změna permeability nepravého jádra bukového dřeva

Dömény, Jakub January 2012 (has links)
No description available.
36

Analýza přirozené obnovy smrku ztepilého a vnášení melioračních dřevin na majetku města Počátky

Maršík, Roman January 2013 (has links)
No description available.
37

Monitoring tvorby dřeva buku lesního (Fagus sylvatica L.) na buněčné úrovni

Ondrouch, Tomáš January 2013 (has links)
No description available.
38

Dynamika obnovy jedle a buku v západních Karpatech (Mionší, Razula, Salajka)

Přívětivý, Tomáš January 2013 (has links)
No description available.
39

Vliv lesa na migraci a sedimentaci rizikových prvků a vybrané environmentální problémy

Juřička, David January 2016 (has links)
The research of the dissertation thesis was focused on the ability of forests to activate and immobilize metals in the environment with their huge grants from deep mining of mineral resources. The research was be located in the area of Rožná with ongoing uranium mining, and area of Olší with ended uranium mining in the Czech Republic. During the years 2014 and 2015 was at the alluvial streams of Nedvědička (Rožná) and Hadůvka (Olší) recipients of pollution by radionuclides and metals from mining, taken in spring and autumn aspect of the overall 380 samples of leaves from trees, herb layer and river sediments. The samples were analyzed by the XFR and ICP-OES methods. In the organic matter were found such as elements Al, Cl, Cu, Cr, Fe, Mn, Mo, Ni, Rb, S, Sr, U, Zn and Zr, in many cases at high concentrations corresponding to polluted areas in the mining or industrial areas. A statistically significant difference in the concentrations of chemical elements in the fytomasss and river sediment between the upper, middle and lower stream areas of interest was not found. In the area of Nedvědička were found higher concentrations of a greater range of metals than in the area of Hadůvka. In the area of Hadůvka were by ICP-OES found significantly higher levels of uranium in the leaves than in the area of Nedvědička, reaching up to 34.86 mg.kg-1 in the dried material.The seasonal dynamics of the content of chemical elements in fytomass was confirmed. The species composition of the forest growth in the areas of interest with a predominance of Picea abies and the type of management has been evaluated as unfavorable for immobilization of metals in the environment. In the area of Nedvědička were suggested corrective actions - planting vegetation with a predominance of Fagus silvatica which should have a beneficial effect on soil and water pH by a suitable character of waste and contribute to the spread of inhibition of metals in the environment. In the area of Hadůvka are the suggested measures focused on the redevelopment of existing vegetation with a predominance of Picea abies on vegetation with a predominance of deciduous trees, especially Fagus silvatica, in order to adjust gradually the pH of the soil and thereby reduce the mobility of metals in the environment.
40

Uticaj klimatskih promena na vezivanje ugljenika, rast i biodiverzitet bukovih šuma u Srbiji / The impact of climate change on carbon sequestration, growth and biodiversity of European beech forests in Serbia

Stojanović Dejan 30 June 2014 (has links)
<p>Prognoze Međuvladinog panela o klimatskim promenama govore da će&nbsp;prostor Jugoistočne Evrope biti&nbsp; pod snažnim uticajem izmenjenih klimatskih&nbsp;uslova u 21. veku. Očekuje se da će leta biti toplija i suvlja sa vi&scaron;e&nbsp;ekstremnih događaja i temperaturama koje mogu u proseku porasti i za čak&nbsp;3,8&deg;C, &scaron;to predstavlja veliki izazov za &scaron;umarstvo. Da bi se odgovorilo na taj&nbsp;izazov neophodno je načiniti i sprovesti adekvatne mere adaptacije, &scaron;to bi&nbsp;značilo prilagođavanje mera gazdovanja &scaron;umama novonastlim ekolo&scaron;kim&nbsp;uslovima. Jedan od značajnih alata u tom prilagođavanju predstavljaju&nbsp;različiti &nbsp;modelarski pristupi. U&nbsp; ovoj disertaciji su upotrebljene&nbsp;najsavremenije metode modeliranja uticaja klimatskih promena na &scaron;ume.&nbsp;Radi se o pionirskom istraživanje koje je prvo takve vrste u regionu. Dva&nbsp;različita metodska pristupa, vezanih za distribuciju, rast, adaptivno i&nbsp;multifunkcionalno gazdovanja bukovim &scaron;umama u Srbiji u klimatskim&nbsp;uslovima 21. veka su uputila na nekoliko najbitnijih rezultata i zaključaka. &nbsp;Izmenjeni klimatski uslovi će imati uticaj na rast i distribuciju bukovih &scaron;uma&nbsp;u 21. veku na osnovu simulacija sa 4C modelom i predikcija pomoću&nbsp;Elenbergovog koeficijenta. Na &nbsp;kraju simuliranog perioda 2001-2030 pomoću&nbsp;4C modela zabeležene su &nbsp;veće zapremine za devet sastojina&nbsp;monodominantnih bukovih &scaron;uma u odnosu na referentni period 1961-1990,&nbsp;dok su zapremine na kraju perioda 2071-2100 po pravilu bile veće ili &nbsp;slične&nbsp;referentnom period. Simulacije u period 2001-2030 su proseku imale najveće&nbsp;godi&scaron;nje priraste i najvi&scaron;e mrtvog drveta, a one u period 1961-1990 &nbsp;najmanje.&nbsp;Najbolje rezultate za vezivanje ugljenika i očuvanje biodiverziteta je pokazao&nbsp;scenario gazdovanja u kojem nije bilo intervencija. Suprotno tome, &nbsp;najvi&scaron;e prinosa drveta je zabeleženo u scenarijima sa najintenzivnijim&nbsp;intervencijama. U adaptivnom multifunkcionalnom gazdovanju bukovim&nbsp;&scaron;umama za scenarija preferencija koje su kreirale tri grupe zainteresovanih&nbsp;strana (Uprava za &scaron;ume, sektor za&scaron;tite prirode i JP &bdquo;Srbija&scaron;ume&ldquo;) pokazalo se&nbsp;da gazdovanje koje podrazumeva če&scaron;će zahvate (pet godina između seča)&nbsp;daje bolje rezultate u odnosu scenarija koji podrazumevaju desetogodi&scaron;nje&nbsp;intervale. Scenariji gazdovanja u kojima su posečena visoka stabla su&nbsp;pokazale bolje rezultate u multifunkcionalnom gazdovanju u odnosu na&nbsp;scenarija gde su sečena niža stabla u istom zapreminskom odnosu za sva&nbsp;<span style="font-size: 12px;">scenarija preferencija zainteresovanih strana. Elenbergov koeficijent je&nbsp;</span><span style="font-size: 12px;">pokazao dobru prediktivnu sposobnost za određivanje donje granice&nbsp;</span><span style="font-size: 12px;">distribucije bukovih &scaron;uma u &nbsp;Srbiji. Do kraja 21. veka okvirno 90% dana&scaron;njih&nbsp;</span><span style="font-size: 12px;">bukovih &scaron;uma će se naći izvan bioklimatske ekolo&scaron;ke ni&scaron;e u kojoj su bili u&nbsp;</span><span style="font-size: 12px;">20. veku, dok će se 50% naći u zoni u kojoj je &nbsp;zabeležen njen masovni&nbsp;</span><span style="font-size: 12px;">mortalitet u Mađarskoj. Izračunate granice EQ su bile ne&scaron;to niže od dobijenih&nbsp;</span><span style="font-size: 12px;">u sličnim studijama u region &scaron;to implicira striktan regionalni i lokalni pristup&nbsp;</span><span style="font-size: 12px;">problem. Poređenje rezultata simulacija sa 4C modelom i EQ za posmatranih&nbsp;</span><span style="font-size: 12px;">devet sastojina je pokazalo različite trendove vezano za rast (distribuciju)&nbsp;</span><span style="font-size: 12px;">bukovih &scaron;uma u Srbiji do kraja 21. veka. 4C model je predvideo pobolj&scaron;anje&nbsp;</span><span style="font-size: 12px;">uslova, dok je EQ predvideo pogor&scaron;anje uslova. Iz tog razloga potrebna su&nbsp;</span><span style="font-size: 12px;">dalja kontinuirana dugoročna istraživanja bukovih &scaron;uma kako bi smo dobili&nbsp;</span><span style="font-size: 12px;">pouzdaniju osnovu za procenu budućeg rasprostranjenja, rasta i planiranja&nbsp;</span><span style="font-size: 12px;">gazdovanja ovim &scaron;umama u budućnosti.</span></p> / <p>Predictions of the Intergovernmental Panel on Climate Change suggest that&nbsp;the region of Southeast Europe will be strongly influenced by the altered&nbsp;climate conditions in 21 century. It is expected that the summers will be&nbsp;hotter and drier with more extreme events and temperatures that can rise on&nbsp;average as much as 3.8 &deg;C. That is a big challenge for forestry. To respond&nbsp;to this challenge it is necessary to make and implement appropriate&nbsp;adaptation measures which would mean adapting forest management&nbsp;practice to changed environmental conditions. Different models are one of&nbsp;the important tools which can be used in this purpose. In this dissertation&nbsp;state-of-the art methods for calculating the impact of climate change on&nbsp;forests have been applied. This is a pioneering work and the first of its kind&nbsp;in the region. Two different methodological approaches, related to the&nbsp;distribution, growth, adaptive and multifunctional management of&nbsp;European beech forests in Serbia has been performed and provided&nbsp;following results and conclusions. Changed climatic conditions will have&nbsp;<br />an impact on the growth and distribution of beech forests in 21st century&nbsp;based on simulations with the 4C model and predictions of Ellenberg&rsquo;s&nbsp;climate quotient (EQ). At the end of the simulated period 2001-2030 higher&nbsp;volumes were recorded for the nine beech stands in comparison to the&nbsp;reference period 1961 to 1990, while the volume at the end of the period&nbsp;2071-2100 were higher or similar to the reference period. Simulations in&nbsp;the period 2001-2030&nbsp; have had the greatest average annual increment and&nbsp;the biggest amount of dead wood. The best results for carbon sequestration&nbsp;and biodiversity were provided by management scenario in which there&nbsp;were no management measures. In contrast, the highest yield&nbsp; of timber is&nbsp;recorded in the scenarios with the most intensive management measures.&nbsp;The adaptive multifunctional &nbsp;management of beech forests including three&nbsp;<span style="font-size: 12px;">scenarios of preferences&rsquo; (Forest Directorate , Nature Protection Sector and&nbsp;</span><span style="font-size: 12px;">Public Enterprise &quot;Srbija&scaron;ume&quot; ) suggested that management measures that&nbsp;</span><span style="font-size: 12px;">involved more frequent interventions (five years between felling) gives</span><span style="font-size: 12px;">better results than scenario which include a ten-year periods. Scenarios in&nbsp;</span><span style="font-size: 12px;">which higher trees are cut provide better results than scenario where the&nbsp;</span><span style="font-size: 12px;">lower trees are cut. EQ showed good predictive capability for determining&nbsp;</span><span style="font-size: 12px;">the lower (xeric) limit of the distribution of beech forests in Serbia. By the&nbsp;</span><span style="font-size: 12px;">end of 21st century, approximately 90 % of today&#39;s beech forests will be&nbsp;</span><span style="font-size: 12px;">found outside the bioclimatic niches in which they were in the 20th century,&nbsp;</span><span style="font-size: 12px;">while the 50 % of them will be in the zone in which their mass mortality is&nbsp;</span><span style="font-size: 12px;">observed in Hungary. Calculated EQ beech threshold distribution for Serbia&nbsp;</span><span style="font-size: 12px;">were slightly lower than in similar studies in the region (Hungary) , which&nbsp;</span><span style="font-size: 12px;">implies strict regional and local approach to the problem. Comparison of&nbsp;</span><span style="font-size: 12px;">simulated results with the 4C model and EQ for nine stands showed </span><span style="font-size: 12px;">different trends related to growth (distribution) of beech forests in Serbia by&nbsp;</span><span style="font-size: 12px;">the end of 21st century. 4C model predicted improvement of environmental </span><span style="font-size: 12px;">conditions, while the EQ predicted their worsening. For this reason,&nbsp;</span><span style="font-size: 12px;">continuing long-term studies of beech forests are needed in order to get a&nbsp;</span><span style="font-size: 12px;">more reliable basis for estimating future distribution, growth and planning&nbsp;</span><span style="font-size: 12px;">of forest management in the future.</span></p>

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