In Lithuania, it is a first genetic study that analyses the DNA polymorphism of Scots pine at the level of cell’s nucleus and organelle’s genomes. In Europe, it is one of the first studies of DNR-based population structure covering in detail the eastern range of Scots pine, where the populations originate from Scotland in the west up to the Amur river estuary in the east. Our material represents a great magnitude of adaptive environments including the core populations at the central part of the species range as well as the marginal populations. The analysis was performed using high resolution and repeatability microsatellite DNA markers. / Tai yra pirmas genetinis mokslinis darbas Lietuvoje, nagrinėjantis paprastosios pušies DNR polimorfizmą ląstelės branduolio ir organoidų genomų lygmenyse. Europoje tai vienas iš pirmųjų mokslinių darbų, detaliai analizuojantis DNR polimorfizmą rytinėje paprastosios pušies rūšies arealo dalyje. Darbe lyginamos populiacijos, pradedant Škotija vakaruose, baigiant Amūro upės žiotimis tolimuose rytuose. Taip reprezentuojamas visas adaptacinių aplinkų gradientas: Europa–Uralas–Tolimieji Rytai. Tyrimui naudoti aukštos genetinės rezoliucijos ir patikimo pakartojamumo mikrosatelitinės DNR žymenys.

The defence mechanisms expressed in roots of Pinus sylvestris seedlings challenged with fungal pathogens were investigated, and a comparison was made between the expression of defences in non-mycorrhizal and mycorrhizal seedlings. Papillae were formed by cortical cells of non-mycorrhizal seedlings infected with Cylindrocarpon destructans. Histochemical evidence was obtained for pectic materials comprising an important polysaccharide component of these structures, and for the deposition of polyphenolic compounds also. Proton induced X-ray emission (PIXE) microanalysis indicated that insoluble calcium levels were elevated in papillae relative to normal cell walls. Although papillae appeared important in protecting cortical cells against penetration by fungal hyphae, a primary role for the wall appositions in the resistance of seedlings of Scots pine against root pathogens could not be proven. Although phytoalexins were not detected in the roots of Scots pine seedlings following infection with C. destructans, the mean content of an abietic acid fraction (comprising six compounds, of which only dehydroabietic acid could be positively identified), increased from 5.2 to 9.7mg g^-1 dry weight. This fraction exhibited some antifungal activity. -related proteins induced de novo by infection could not be detected, but several constitutive apoplastic proteins, including some with chitinase activity, appeared to increase in the needles of root-infected seedlings. The formation of ectomycorrhizae with Pisolithus tinctorius, Suillus bovinus and Hebeloma crustuliniforme did not itself induce papilla formation in the roots of P. sylvestris. Evidence was obtained to suggest that the response was suppressed when mycorrhizal seedlings were challenged with C. destructans. Results highly suggestive of the induction of systemic resistance in P. sylvestris seedlings, consequent upon mycorrhizal infection, were obtained. In seedlings grown in vitro the survival rate of mycorrhizal seedlings challenged aerially with Botrytis cinerea was 37.5% compared with 7.1 in seedlings grown gnotobiotically. However, the physiological mechanisms by which this protection was imparted remain to be determined.

The effects of sewage sludge application and the additional effects of clearfelling on nutrient cycling have been assessed in a mature Scots pine stand, north-east Scotland. The forest site was situated in a low rainfall area with high evapotranspiration and low leaching losses. The ground vegetation formed an important sink for N and P following sludge addition and clearfelling. Sludge application caused a foliar N response, increased foliar needle weight, and litterfall showed a significant and rapid potential to immobilize NH₄-N and PO₄-P added in sludge. The soil availability of NH₄-N and PO₄-P together with rates of mineralization of N and P and nitrification in sludge-treated areas were significantly increased compared with that of the control. Concentrations of NH₄-N, NO₃-N, PO₄-P and organic P were increased significantly following sludge addition and fluxes were an order of magnitude greater than that of the control. Peaks in concentrations of NH₃-N in sludge-treated areas exceeded the EC limit of 11.3 mg 1^-1 on several occasions. Of the total N and P applied to the sludge, throughfall and litterfall over a 17 month period, 2.4 % and 0.72 % were measured in the B_s soil horizon flux. After clearfelling, initial increases in soil availability of NH₄-N, NO₃-N andPO₄-P were measured. Felling increased nitrification rates, although increases were significant only in areas previously treated with sludge. Fluxes of NO₃-N, NH₄-N and PO₄-P and organic P were increased at least an order of magnitude greater in felled areas than those of the control. Immobilization of N and P was greater in green and abscised litters placed in previously sludge-treated areas than compared with those placed in control areas.

No description available.

Drought-induced tree mortality is a phenomenon affecting many forest ecosystems and is predicted to increase under ongoing climate change. Forest stability partly depends on regeneration: the process of renewing mature forest with subsequent generations. As seedlings are more susceptible to drought effects than mature trees, mortality of the seedling bank can represent a major bottleneck controlling forest structure and species composition. Scots Pine (Pinus sylvestris L.) is the most widely distributed of the Pinus species, covering a broad latitudinal gradient of ecological conditions. The thesis aims to deepen understanding of drought-induced mortality, while analysing intra-specific variation in the phenotypic and metabolic profile of Pinus sylvestris seedlings subjected to drought stress. I also consider the relevance of the results to the broader conceptual framework of drought-induced mortality. The experiments utilise seeds from different populations of origin (provenances) across the north-south axis of the European range of Pinus sylvestris, in order to determine the extent of regeneration capacity in this species under drought. Seeds were collected from different populations (provenances) that, along with other climatic and edaphic differences, span a gradient of water availability: from wet (Scotland) to intermediate (Austria, Poland) to dry (Spain). In Chapter 2, the effects of osmotic stress on the initial seedling establishment stage were studied by comparing phenotypic responses across provenances. Seedling germination, early growth, osmotic stress tolerance and survival were investigated using a polyethylene glycol irrigation treatment as a proxy for rapid and severe drought. Treatment, provenance and interaction effects were found for rate of germination, final proportion of seeds germinated, seedling size, and superoxide dismutase activity (an antioxidant enzyme). Root investment was affected by both provenance and time to germination. Although there was no significant effect of provenance on survival, a trend towards increased probability of survival under osmotic stress was indicated for the southernmost (driest) as compared with the northernmost (wettest) provenance. Chapter 3 investigates the responses of older seedlings (at 10 months) to a drying down of soil moisture for 40 days. Morphological and physiological data were collected to assess intra-specific and intra-population variation in the seedling stress response under drought. A metabolomics analysis using Ultra performance Liquid chromatography followed by mass spectrometry (UPLC/MS) was carried out to investigate whether metabolic markers could be identified that are suggestive of heightened oxidative stress and whether populations in different climatic and edaphic environments show variation in metabolic activity under drought. Preliminary results suggest large intra-population variability yet clear differentiation in metabolic responses to drought over the time course of the experiment. Univariate and multivariate analyses indicated that among the most significant increases in response to drought were those involved in osmoprotective and antioxidant capabilities, including the free amino acid proline and a quercetin derivative (a flavonoid). Interestingly, provenances, either under experimental drought or not, did not show significantly different metabolite profiles, even though provenance and its interaction with drought treatment did significantly affect seedling biomass and photochemical efficiency. In Chapter 4 the effects of provenance, maternal parentage and seed weight on germination rate, final germination percentage, as well as seedling drought responses in biomass allocation and the expression of selected antioxidant genes were analysed. Seed weights were measured individually and seed weight was found to have a strong positive effect on: germination rate, seedling dry weights, and number of needles. Expression of two antioxidant enzymes increased under drought. Seed weight was strongly determined by provenance and maternal parentage as well as their interaction. However, root to shoot biomass allocation depended on provenance and maternal effects that were not mediated by seed weight effects. Principal component analysis indicated that the Spanish provenances could be characterised by a higher root to shoot ratio and stem weight. Specific leaf area was also found to be lowest for the Spanish provenances.

Abstract The genetic basis of large adaptive differences in timing of bud set and frost hardiness between natural populations of Scots pine (Pinus sylvestris L.) was studied with the aid of RAPD markers and quantitative genetic tools. Steep clinal variation was found for both traits among Finnish Scots pine populations, and the differences between populations were found to be largely genetic. QTL mapping with Bayesian analysis revealed four potential QTLs for timing of bud set, and seven for frost hardiness. The QTLs were mostly different between the two traits. The potential QTLs included loci with large effects, and additionally smaller QTLs. The largest QTLs for bud set date accounted for about a fourth of the mean difference between populations. Thus, natural selection during adaptation has resulted in fixation of genes of large effect. This result is in conflict with the classical infinitesimal model, but agrees with the results of Orr (1998), suggesting fixation of large effects during adaptation. The applicability of RAPD and SSCP markers in quantitative genetic studies was also studied. The SSCP technique was found to be efficient in finding polymorphic markers. SSCP polymorphism in coding genes may provide candidate genes for QTL mapping studies. RAPDs were found to be useful for many descriptive analyses, but specific analyses would require more caution.

For the first time in Lithuania the foliage spectral reflectance properties of common tree species were investigated using hyperspectral imaging. The methodological outline was formulated and the procedures of practical hyperspectral imaging application were developed to stimulate the progress of hyperspectral remote sensing in Lithuanian forestry. Information extracted from foliage hyperspectral reflectance data was used to accurately determine forest tree species and the provenances of Scots Pine trees. The satisfactory results of determination of Scots Pine crown defoliation and the concentration of some needles chemical constituents were achieved investigating the foliar hyperspectral reflectance, too. The first spectral libraries of common Lithuanian tree species foliar reflectance were built considering the growing season. / Suformuoti hiperspektrinio skenavimo naudojimo įvairioms miško medžių savybėms tirti metodiniai ir praktiniai pagrindai – sukurtos ir išbandytos mėginių paėmimo, jų paruošimo skenuoti, skenavimo atlikimo ir gautos informacijos apdorojimo metodikos, kurios aprobuotos vykdant mokslinius tyrimus. Nustatyti vegetacijos sezono momentai, kuriais skirtingų miško medžių rūšių atpažinimas nuotoliniu būdu pagal jų spektrinus atspindžius būtų tiksliausias, o tai sudaro prielaidas tobulinti kitas nuotoliniais. Pasiūlyti metodai paprastosios pušies spyglių kai kurių cheminių elementų koncentracijai nustatyti naudojant hiperspektrinį skenavimą. Sukurtos Lietuvos miškuose augančių pagrindinių medžių rūšių lapijos spektrinio atspindžio kreivių bibliotekos, naudotinos miškų inventorizacijoje, kalibruoti ir klasifikuoti orlaiviuose sumontuotais jutikliais išgautus Lietuvos medynų hiperspektrinius vaizdus.

Four regional Scots pine ring-width chronologies at the northern forest-limit, and in the northern, middle and southern boreal forest belts in Finland cover the last fourteen centuries. Tree-ring statistics and response functions were examined, and tree-ring width variation was also compared to North Atlantic Oscillation (NAO) and volcanic forcing. The tree-ring statistics show evidence of an ecogeographical gradient along a north-south transect. The three northernmost regional chronologies share a positive response to mid-summer temperature, and all four chronologies show positive and significant correlation to early-summer precipitation. Moreover, a positive and significant relationship to winter NAO was detected in three out of four regional chronologies. NAO also drives the common (inter-regional) growth variability. Years of known cool summers caused by volcanic forcing exhibit exceptionally narrow tree rings in the three northernmost regional chronologies.

In this dissertation is analysed the transfer of artificial radionuclides (137Cs and 90Sr) from soil to tree. The main goal of this work – to estimate specific activi-ties of 137Cs and 90Sr in selected trees, investigate the peculiarities of these ra-dionuclides distribution in trees, suggest the methodology for estimation of the transfer of radionuclides from soil to tree in tree wood by chemical analog in soil under the tree crown, and to do the forecast of transfer of radionuclides in sys-tem “soil–tree” by the most relevant models. The main tasks solved in this dissertation are following: to do the radiomet-ric, radiochemical and biological affections researches of selected pines, evalu-ate the specific activity and concentration in collected samples of investigated radionuclides and their chemical analogs, apperciate the transfer of 137Cs and 90Sr from soil to tree and analyse peculiarities of this process by soil radioactive pollution and plants growing peculiarities; to modelling the spread of 137Cs and 90Sr distribution in system “soil–plant”, the accumulation of these radionuclides in tree and internal doses. This dissertation consists of introduction, five chapters, the main conclusion and recommendation, bibliography and list of author publications. In the introduction it is discussed the investigated problem, actualities of work, object of research, scientific novelty and practical significant of this dis-sertation, protective hypotheses. Additionally it is... [to full text] / Disertacijoje nagrinėjama dirbtinės kilmės radionuklidų (137Cs ir 90Sr) per-naša iš dirvožemio į medį. Pagrindinis šio darbo uždavinys – nustatyti 137Cs ir 90Sr savituosius aktyvumus tyrimui parinktuose medžiuose bei įvertinti šių ra-dionuklidų pasiskirstymo juose ypatumus, pasiūlyti metodiką radionuklido per-našos iš dirvožemio į medį vertinimui pagal radionuklido cheminį analogą dir-vožemyje po medžio laja, atlikti radionuklido pernašos iš dirvožemio į medį prognozę, parinkus tinkamiausius modelius. Šiame darbe sprendžiami tokie pagrindiniai uždaviniai: atlikti medžių sandų radiometrinius, radiocheminius ir pušų biologinio pažeistumo tyrimus; įvertinti tiriamųjų radionuklidų ir jų stabiliųjų cheminių analogų savituosius aktyvumus bandiniuose; įvertinti 137Cs ir 90Sr pernašos iš dirvožemio į medžius ir pasiskirs-tymo juose ypatumus, atsižvelgiant į dirvožemio radioaktyviąją užtaršą ir augalo vystymosi ypatumus; modeliuoti 137Cs ir 90Sr migracijos sistemoje „dirvožemis–medis“ sklaidą, įvertinti radionuklidų sukauptą augale kiekį, modeliuoti augalo patiriamą vidinę apšvitą. Disertaciją sudaro įvadas, penki skyriai, bendrosios išvados, rekomendaci-jos, naudotos literatūros ir autorės publikacijų sąrašai. Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, apra-šomas tyrimų objektas, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Pristatomos disertacijos tema autorės paskelbtos publikacijos, pranešimai, disertacijos struktūra... [toliau žr. visą tekstą]

Investigations of interactions between climate change and humans suffer from the lack of climate proxies directly linked to historical or archaeological datasets that describe past environmental conditions at a particular location and time. We present a new set of pine tree-ring records (Pinus sylvestris L) developed from burial timbers excavated at the historical center of Yaroslavl city, Russia. A 171 year delta C-13 tree-ring chronology from AD 1430 to AD 1600 evidences mostly wet summers during the 15th century but exceptionally dry conditions of the 16th century at the Upper Volga catchment. According to the tree-ring record there were four major droughts (<-1.5 sigma) lasting from 9 to 26 years: 1501-1517, 1524-1533, 1542-1555 and 1570-1596, and major pluvials (>+1.5 sigma) lasting from 70 to 5 years: 1430-1500, 1518-1523, 1534-1541, and 1556-1564. We discuss a plausible contribution of these droughts to crop failures and city fires documented with historical chronicles for the Upper Volga catchment. The devastating drought regime of the 16th century corresponds to the loss of independence of the Yaroslavl principality to the Grand Duchy of Moscow and the formation of the centralized Russian State during the reign of Ivan the Terrible (1533-1584) underpinning the emergence of the Russian Empire. This study substantiates the value of archaeological timbers from the oldest Russian cities and inclusion of stable carbon isotope analysis for understanding hydroclimatic regimes across the mid latitudes of East European Plain, and their relationship to the history of Russia. (C) 2016 Elsevier GmbH. All rights reserved.