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Objective of the study is to assess wood yield and quality of Polish Norway spruce provenances and transfer effect in comparison with the local provenances. Object of the study is experimental plantation established in Kazlų Rūda EFE, Agurkiškės forest district (62 comp.., 43 plot). Six southern Polish proveniences were from Istebna, Ustron, Ujstoly ir Lagow forest districts and three open-pollinated families from Girionys seed orchard and progeny from the local Agurkiškės forest district were tested. Area of the experimental plantations 1,8 ha. Methods: quantitative and qualitative traits of the trees in the plantation were assessed by using the following tools and methods: height was measured with a telescopic pole, diameter with calipers and the quantitative traits were assessed by the standard methods used in genetics and breeding. Results: this study showed that growth rate and wood yield of the southern provenances were higher than of the progenies of the selected plus trees of Lithuanian origin. However, wood yield of soother Polish provenances was significantly higher than that of the local regular stands of Agurkiškių provenance. This indicates, that the seed orchard material is superior over the material form regular unimproved forests stands. This difference may be caused not only by the geographical transfer effect but also related to genetic quality of the original stands. Polish provinces possessed a lower number of forked trees but their stems were less... [to full text]

Magistro darbe tiriamas dirvos paruošimo būdo ir pasodinimo vietos įtaka eglės želdiniams. Darbo objektas – Šilutės miškų urėdijos Stemplių, Šiaudėnų ir Žemaičių Naumiesčio girininkijų 1999 - 2005 metų paprastosios eglės želdiniai. Darbo tikslas – nustatyti dirvos paruošimo būdo ir pasodinimo vietos įtaką eglės želdinių prigijimui ir augimui. Darbo metodai – literatūros loginės analizės; apskaitos aikštelių metodas; duomenys apdoroti matematinės statistikos metodais. Darbo rezultatai. Įvertinant dirvos paruošimo būdo ir pasodinimo vietos įtaką eglės želdiniams buvo įvertinti 112 sklypų, iš jų Nc augavietėje 29 sklypuose, Lc – 72 sklypuose, Ld – 11 sklypų. Pagal dirvos ruošimo būdus tyrimo objektai išsidėstė taip: dirva ruošta kauburėliais – 83 objektuose, vagomis - riekėmis (sodinant į šlaitelį) – 15 objektų ir 14 sklypų kai dirva visai neruošta. Pagal medelių pasodinimo vietą tirti objektai pasiskirstė taip: pasodinti kauburėlio viršuje – 36 objektai, kauburėlio šlaite – 47 objektai, vagų – riekių šlaite – 15 objektų ir neruoštoje dirvoje – 14 objektų. Atlikus paprastosios eglės želdinių tyrimus priklausomai nuo dirvos paruošimo būdo ir pasodinimo vietos, gauta jog geriausiai medeliai prigyja, kai dirva ruošta kauburėliais Lc augavietėje. Palyginus gautus duomenis pagal medelių biometrinius rodiklius geriausi rezultatai gauti taip pat, kai dirva ruošta kauburėliais Ld augavietėje. Blogiausiais eglaičių prigijimas ir biometriniai rodikliai yra, kai dirva visai neruošta Lc... [toliau žr. visą tekstą] / In MG work is studding Norway spruce growing depending from soil preparation way and seating place. The work's object - Šilutė's enterprise Stempliai, Šiaudėnai and Žemaičių Naumiestis forestry 1999 – 2005 years Norway spruce plantation. The work's aim - value Norway spruce plantations growth depending from soil preparation way and seating place. The work's methods -literature logical analysis, accounting plots method; statistical methods for data work were used. The work's results. Valued Norway spruce growth depending from soil preparation way and seating place was value 112 plots, from its in Nc place - 29 plots, in Lc - 72 plots, in Ld – 11 plots. From soil preparation way investigation object are: micro rise soil preparation - 83 objects, trench - slice (planting in slant) - 15 objects and in 14 plots when soil not prepared. From sapling growth investigation object divided so: plant in micro rise - 36 objects, micro slant - 47 objects, trench - slice slant - 15 objects and not prepared soil - 14 objects. Navigated Norway spruce plantation investigation depending from soil preparation way and seating place, got, what best plant establishes, when soil preparation micro rise in Lc place. Comparison got information by plant biometrics parameters best result got, when soil preparation in Ld place too. Worst spruce establishes and biometrics parameters are, when soil not prepared in Lc place. In summary, best results find when soil prepared in micro rise.

Darbo objektas - įvairaus amžiaus centrinio puvinio pažeisti eglės medžiai, kurie auga skirtinguose našumo rajonuose. Darbo tikslas – centrinio puvinio paplitimo tipinėse paprastosios eglės augavietėse (Nc, Nd, Lb, Lc, Ld) vertinimo garsiniu tomografu ARBOTOM 3D galimybių tyrimas. Darbo metodai – duomenys apie puvinio išplitimą rinkti naudojant garsinį tomografą Arbotom 3D. Surinkti duomenys apdoroti naudojant MS Excel, Statistica ir Arbotom programas. Atliekant tyrimą buvo naudoti tokie bendrieji metodai: dokumentų analizės, duomenų grupavimo, modeliavimo, loginis, palyginimo, apibendrinimo. Rezultatai – Duomenys buvo renkami 4 gamtiniuose – našumo rajonuose.Tyrimo metu pamatuota 3269 medžiai iš kurių 703 nuskenuota garsiniu tomografu. Darbo metu nustatyta, kad vaizdus, gautus garsinio tomografo Arbotom 3D pagalba, galima apdoroti su 85,44 proc patikimumu. Geriausiai puvinio buvimo stiebe faktą nusako ne absoliutus garso sklidimo greitis medienoje, bet minimalaus ir maksimalaus greičių sklidimo skirtumo santykis su mažiausiu sklidimo greičiu, bei stiebo skersmeniu 1.3 m aukštyje. Modeliuojant puvinio buvimo tikimybę Lietuvos mastu, modelyje tikslinga papildomai naudoti medžių amžių bei našumo rajoną. Didžiausias puvinio pažeistų medžių procentas buvo nustatytas IV (38,7 proc.) ir I ( 37,8 proc) Krafto klasės medžiams, II ir III klasėje pažeistų medžių buvo atitinkamai 28 proc. ir 34 proc. Tyrimų metu nustatyta, kad Lc ir Nc augavietėse puvinio pažeistų medžių dalis yra... [toliau žr. visą tekstą] / Subject of work –Norway spruce trees of various age class, that were damage by core rot in respect to regions of natural forest productivity. Aim of work – to investigate the possibilities of ARBOTOM 3D to identify the spread of core rot in Norway spruce regarding to forest type sites (Nc, Nd, Lb, Lc, Ld). Methods of work – material respecting rot spread were collected using tomography ARBOTOM 3D. Collected data was analyzed using Statistica, Excell and Arbotom software applications The following common scientific methods were used in this research: data analyzes, data grouping, modelling logic, comparison, syntheses. Results of work – The data of the research was collected in 4 State forests enterprises in respect to regions of natural forest productivity. In this study, 27 spruce stands of different age were choosen using random selection. The trees parameters were estimated for 3269 spruces, 703 out of estimated trees were scanned using acoustic tomography to determine the spread of rot inside stems. The reliability of 85.55 percentages was reached using ARBOTOM. The results of research revealed, that the most success approach to identify the rot in a stem was the ratio difference between maximal and minimas velocity to minimum velocity also stem diameter in 1.3 meter. Regarding to rot spread modelling in Lithuania it is advisable to use the ages of trees and regions of natural forest productivity additionally. The data of the research revealed that the most rotted... [to full text]

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No description available.

A dendrochronological and dendrochemical study was undertaken near the village of Kuujjuaq, northern Quebec. Changes in climate, radial growth and mineral nutrition of trees, as well as the contamination in Mn and Zn of tamarack and black spruce forests of the region during the last forty years were investigated. A growth model based on climatic variables was produced for each species. The regional climate didn't show any steady trend of increase in temperature and precipitation with time. However, the 1953-1964 decade was the warmest one and the 1964-1973 decade received the most precipitation. Radial growth of both species have probably increased during the investigated period. Growth of larch was primarily associated with May and June precipitation (R$ sp2$ = 0.134) when spruce growth was associated with spring temperature and July and August evapotranspiration (R$ sp2$ = 0.352). Wood chemistry (concentration, burden, and elemental ratio) suggests a stable soil fertility in base cations during the last forty years as well as a stable or increased availability of Zn during the last decade. More extensive research, in terms of number of sites and variables studied could confirm the observed trends in growth, soil fertility, and Mn and Zn availability in this part of northern Quebec.

Trembling aspen (Populus tremuloides Michx.) were observed growing along roads far north from the area where it dominates, in sites dominated by black spruce (Picea mariana (Mill.) B.S.P.) forests. This study examined the distribution of aspen at an early development stage and the conditions in which they are growing in a black spruce/feathermoss forest type in northwestern Abitibi, Quebec six years following harvesting. In this region, aspen are appearing in logged and burned areas that had been previously dominated by black spruce. The relationship of aspen growth with Ca availability and mineral soil access is the main focus of the study. Soil and foliar samples from aspen seedlings were collected from roadside, slash and cutover locations during the summer of 2003. Trees were also measured for height and basal diameter. Microsites where aspen was growing and where it was absent were compared to determine whether aspen was associated with specific microsites soil properties. The results suggest that there are differences in the growing conditions for aspen between different locations but that the trees are growing successfully in all of the three location types. In the cutovers, aspen seedlings were consistently found in association with patches of Polytrichum moss. All the sets of data indicate that Ca availability and access to mineral soil are not the main factors influencing the distribution of aspen but that soil pH, or a factor relating to pH, may be important.

Trembling aspen (Populus tremuloides (Michx.)) has become established along a mining road in the lower northern Quebec region (49°39' to 49°45'N and 79°01' to 79°02' W) in areas that have not supported aspen in the past. The primary means of regeneration of aspen is through vegetative root suckers, but it is doubtful that it could progress through this region at such a fast rate solely by asexual reproduction. Aspen are known to produce large amounts of seeds that could account for aspen's rapid progression, but sexual reproduction of aspen is rare; very little is known about Populus tremuloides seed germination and seed survival in natural conditions. The aim of this study was to determine seedbed conditions that facilitate the emergence and survival of Populus tremuloides seedlings, and to identify the key factors involved in these processes. Observations of established saplings and a sowing experiment were conducted on both post harvest and post fire sites. Our data on established saplings showed that there were seed-origin trembling aspen located in both post-harvest and burned areas indicating that Populus tremuloides can and has established from seed in areas where aspen was previously absent. Both our sowing experiment and our greenhouse experiment showed that the emergence of seedlings was relatively low, but that Polytrichum strictum moss and exposed mineral soil depressions were the best seedbeds for seed germination. Extreme temperatures and availability of moisture appeared to be controlling factors on seed germination, but ultimately the physical and biological characteristics of each substrate influenced the substrate's response to these factors in a different way. We conclude that sexual reproduction of trembling aspen may and has occurred in this region, and is promoted by the presence of exposed mineral soil and Polytrichum strictum moss. / Keywords: Bryophytes, Populus tremuloides, Polytrichum, Sphagnum, seedling, seedbed, germination, seed.

In Canada, the endangered prairie skink (Plestiodon septentrionalis) exists only in southwestern Manitoba. Habitat loss is the most significant threat faced by the prairie skink in Canada, with leafy spurge (Euphorbia esula) invasion identified as one of the suspected factors contributing to habitat loss. The objectives of this study were to determine microhabitat preferences and effect of leafy spurge on prairie skinks in southwestern Manitoba. To determine microhabitat preferences, occupied sites were compared to unoccupied sites. Artificial cover was identified as the most important microhabitat element. To determine the impacts of spurge on microhabitat, ground temperatures in invaded were compared to un-invaded sites. No significant differences in temperature or skink density were observed between invaded and un-invaded site; however, skinks were more likely to use spurge when cover was present, than when no cover was present. Artificial cover may improve microhabitat by providing refuge from predators and microhabitat for prey.