Browsing by Subject "Picea abies"

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  • Virjamo, Virpi; Fyhrquist, Pia; Koskinen, Akseli; Lavola, Anu; Nissinen, Katri; Julkunen-Tiitto, Riitta (2020)
    Knowledge about the defensive chemistry of coniferous trees has increased in recent years regarding a number of alkaloid compounds; in addition to phenolics and terpenes. Here, we show that Norway spruce (Picea abies (L.) H. Karst.), an important boreal zone tree species; accumulates 1,6-dehydropinidine (2-methyl-6-(2-propenyl)-1,6-piperideine) in its needles and bark. We reanalyzed previously published GC-MS data to obtain a full picture of 1,6-dehydropinidine in P. abies. 1,6-dehydropinidine appeared to especially accumulate in developing spring shoots. We used solid-phase partitioning to collect the alkaloid fraction of the sprouts and thin-layer chromatography to purify 1,6-dehydropinidine. The antibacterial properties of the 1,6-dehydropinidine fraction were tested using a broth microdilution method; with Streptococcus equi subsp. equi as a model organism. Based on our results 1,6-dehydropinidine is common in alkaloid extractions from P. abies (0.4 +/- 0.03 mg g(-1) dw in mature needles) and it is especially abundant in young spruce shoots (2.7 +/- 0.5 mg g(-1) dw). Moreover; 1,6-dehydropinidine extracted from P. abies sprouts showed mild antibacterial potential against Streptococcus equi subsp. equi (MIC 55 mu g mL(-1)). The antibacterial activity of a plant compound thought of as an intermediate rather than an end-product of biosynthesis calls for more detailed studies regarding the biological function of these coniferous alkaloids
  • Kallio, Tauno (Suomen metsätieteellinen seura, 1971)
  • Sirén, Gustaf (Suomen metsätieteellinen seura, 1950)
  • Valsta, Lauri. (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1992)
  • Trotsiuk, Volodymyr; Hartig, Florian; Cailleret, Maxime; Babst, Flurin; Forrester, David I.; Baltensweiler, Andri; Buchmann, Nina; Bugmann, Harald; Gessler, Arthur; Gharun, Mana; Minunno, Francesco; Rigling, Andreas; Rohner, Brigitte; Stillhard, Jonas; Thurig, Esther; Waldner, Peter; Ferretti, Marco; Eugster, Werner; Schaub, Marcus (2020)
    The response of forest productivity to climate extremes strongly depends on ambient environmental and site conditions. To better understand these relationships at a regional scale, we used nearly 800 observation years from 271 permanent long-term forest monitoring plots across Switzerland, obtained between 1980 and 2017. We assimilated these data into the 3-PG forest ecosystem model using Bayesian inference, reducing the bias of model predictions from 14% to 5% for forest stem carbon stocks and from 45% to 9% for stem carbon stock changes. We then estimated the productivity of forests dominated by Picea abies and Fagus sylvatica for the period of 1960-2018, and tested for productivity shifts in response to climate along elevational gradient and in extreme years. Simulated net primary productivity (NPP) decreased with elevation (2.86 +/- 0.006 Mg C ha(-1) year(-1) km(-1) for P. abies and 0.93 +/- 0.010 Mg C ha(-1) year(-1) km(-1) for F. sylvatica). During warm-dry extremes, simulated NPP for both species increased at higher and decreased at lower elevations, with reductions in NPP of more than 25% for up to 21% of the potential species distribution range in Switzerland. Reduced plant water availability had a stronger effect on NPP than temperature during warm-dry extremes. Importantly, cold-dry extremes had negative impacts on regional forest NPP comparable to warm-dry extremes. Overall, our calibrated model suggests that the response of forest productivity to climate extremes is more complex than simple shift toward higher elevation. Such robust estimates of NPP are key for increasing our understanding of forests ecosystems carbon dynamics under climate extremes.
  • Kallio, Tauno (Suomen metsätieteellinen seura, 1974)
  • Finér, Leena (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
    Biomass, biomass increment and nutrient cycling were studied in (1) a Scots pine (Pinus sylvestris) stand, (2) a Norway spruce (Picea abies) stand and (3) a mixed birch (Betula pubescens)/pine stand on a drained mire at Ilomantsi, eastern Finland in 1979-85. In addition, the effect of NPK and micronutrient fertilizer treatment was studied. Above-ground and root measurements were taken. These data formed the basis of stand biomass and nutrient cycle simulations of fertilized and unfertilized stands. The increases in biomass were greater in (1) and (2) in the fertilized simulation than in the unfertilized one. For (3), the effect of fertilization on biomass increment was small. In six years only part of the applied fertilizer had been fixed in the biomass of the model stands and proportionally less micronutrients than macronutrients. The potassium stores were small compared to the nutrient amounts fixed by the stands. This supports the notion that there is a shortage of potassium on deep-peat soils.
  • Haikarainen, Iikka (Helsingfors universitet, 2016)
    Metaani (CH4) on yksi tärkeimmästä kasvihuonekaasusta. Sen ilmastoa lämmittävä vaikutus on 100 vuoden lämmi-tyspotentiaalina 28-kertainen hiilidioksidiin verrattuna. Lisäksi metaanin määrä ilmakehässä on yli kaksinkertaistunut esiteollisen ajan alun jälkeen ja sen lähteiden tuntemisessa on puutteita. Ilmakehän metaanista suurimman osan on arveltu olevan peräisin anaerobisissa olosuhteissa tapahtuvasta metanogeneesistä. Boreaaliset metsät on mielletty CH4-nieluiksi maan hapellisessa kerroksessa tapahtuvan metaaninsitoutumisen vuoksi. Myös puut toimivat CH4-lähteinä joko helpottamalla maassa anaerobisesti syntyneen metaanin pääsyä ilmakehään tai tuottamalla sitä itse. Vaikka ensimmäiset havainnot puiden CH4-päästöistä tehtiin jo lähes 20 vuotta sitten, on vasta viimeaikainen tutkimus osoittanut että puiden CH4-päästöt voivat vaikuttaa huomattavasti metsien CH4-taseeseen. Suurimpien arvioiden mu-kaan puiden vapauttaman metaanin osuus on jopa 10–40 % globaalista CH4-budjetista. Puiden CH4-päästöjen tutki-mus on tähän asti suuntautunut enimmäkseen trooppiselle ja temperaattiselle kasvillisuusvyöhykkeelle, mutta tutki-mus boreaalisella kasvillisuusvyöhykkeellä on jäänyt vähäiseksi. Tämän pro gradu -työn tavoitteena on arvioida boreaalisella havumetsävyöhykkeellä tavanomaisesti esiintyvien kah-den puulajin, hieskoivun (Betula pubescens) ja kuusen (Picea abies), CH4-vuota ja sen vaihtelua kasvukauden alussa. Työn aineistona on käytetty 28.4.–11.6.2015 Hyytiälässä kahdella eri koealalla havaittuja puiden ja metsänpohjan CH4-voita, jotka on mitattu hieskoivujen ja kuusien rungoista ja oksista käyttäen suljettua kammiomittausmenetelmää. Koealoina olivat soistunut alue (metsäkortekorpi), jolta valittiin 4 koepuuta (2 hieskoivua, 2 kuusta) ja kivennäismaa-alue (kuivahko kangas), jolta valittiin yksi koepuu (hieskoivu). Tutkimuksissa havaittiin, että sekä hieskoivut että kuuset toimivat CH4-lähteinä rungoista ja oksista, vaikka ne myös ajoittain sitoivat metaania. Havaitut CH4-vuot olivat suuruusluokaltaan hyvin vaihtelevia. Suurimmat CH4-päästöt ha-vaittiin soistuneella kasvupaikalla kasvavien hieskoivujen rungoista, joissa runkopinta-ala kohtaiset päästöt vähenivät eksponentiaalisesti puun pituusprofiilissa tyvestä latvaa, ja rungon tyveltä mitatut suurimmat päästöt myös kasvoivat kevään edetessä. Soistuneella koealalla puiden runkojen CH4-vuo korreloi maalämpötilojen kanssa sekä positiivisesti (hieskoivut) että negatiivisesti (kuuset). Sadekertymän havaittiin korreloivan negatiivisesti koivujen runkojen vuon kanssa. Muilla taustamuuttujilla (esim. ilman lämpötila, säteily, mahlan virtausnopeus) ei ollut havaittavaa yhteyttä puiden CH4-vuohon. Korrelaatioita ei myöskään havaittu kivennäismaakohteella olleen hieskoivun keskiarvoisten CH4-voiden ja taustamuuttujien välillä. Puiden CH4-vuosta tehtiin yleistys metsikkötasolle, mikä osoitti kuusien päästö-jen (6,15 g ha−1 vrk−1) olevan suurempia kuin hieskoivujen päästöt (5,82 g ha−1 vrk−1) johtuen kuusien oksiin sitoutu-neesta suuremmasta biomassan määrästä verrattuna hieskoivuihin. Tästä syystä kuuset voivat olla merkittävämpiä metaanin vapauttajia kuin hieskoivut. Työn tulokset vahvistavat aiempien tutkimusten havainnot puiden CH4-päästöistä ja osoittavat että myös boreaalisen kasvillisuusvyöhykkeen puilla voi olla merkittävä rooli globaalissa CH4-budjetissa, jossa puiden CH4-vuota ei ole tähän asti lainkaan huomioitu. Hieskoivujen ja kuusien erilainen vaste kasvukauden alkuun, maalämpötilaan ja sateisuuteen viittaa puulajien välisiin eroihin CH4-vuota säätelevissä tekijöissä tai metaanin kuljetukseen liittyvässä fysiologiassa.
  • Lintunen, Anna; Lindfors, Lauri; Kolari, Pasi; Juurola, Eija; Nikinmaa, Eero; Hölttä, Tuomo (2014)
  • Hallaksela, Anna-Maija (Suomen metsätieteellinen seura, 1984)
  • Sarkkola, Sakari; Alenius, Virpi; Hökkä, Hannu; Laiho, Raija; Päivänen, Juhani; Penttilä, Timo (NRC Canada, 2003)
    Size-structural dynamics of naturally established Norway spruce (Picea abies (L.) Karst.) stands growing on peatlands drained for forestry were investigated. The study was based on modelling of diameter at breast height (DBH) distributions of repeatedly measured stands in southern Finland. The Weibull function was used to parameterize the DBH distributions and mixed linear models were constructed to characterize the impacts of different ecological factors on stand dynamics. Initially, the positive skewness of the DBH distributions increased after drainage as a result of increases in stem numbers and a reduction in mean diameters. Simultaneously, the size inequality among trees increased. These changes were due to regeneration and (or) ingrowth and indicated only little competition from the larger trees. Subsequently, the DBH distributions changed from positively skewed to normal and finally to negatively skewed resulting from tree growth and a reduction in the number of small DBH trees. This indicated increased asymmetric intertree competition. Size inequality did not change during this later stage in stand development, suggesting a concurrent component of symmetric competition. Thinnings had little impact on DBH distribution trends. The observed stand dynamics allow the allocation of growth resources to the desired crop component by appropriate silvicultural treatments.
  • Annila, Erkki; Heliövaara, Kari (Suomen metsätieteellinen seura, 1991)
  • Luomajoki, Alpo (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1993)
    Anthesis was studied at the canopy level in 10 Norway spruce stands from 9 localities in Finland from 1963 to 1974. Distributions of pollen catches were compared to the normal Gaussian distribution. The basis for the timing studies was the 50 per cent point of the anthesis-fitted normal distribution. Development up to this point was given in calendar days, in degree days (>5 °C) and in period units. The count of each parameter began on March 19 (included). Male flowering in Norway spruce stands was found to have more annual variation in quantity than in Scots pine stands studied earlier. Anthesis in spruce in northern Finland occurred at a later date than in the south. The heat sums needed for anthesis varied latitudinally less in spruce than in pine. The variation of pollen catches in spruce increased towards north-west as in the case of Scots pine. In the unprocessed data, calendar days were found to be the most accurate forecast of anthesis in Norway spruce both for a single year and for the majority of cases of stand averages over several years. Locally, the period unit could be a more accurate parameter for the stand average. However, on a calendar day basis, when annual deviations between expected and measured heat sums were converted to days, period units were narrowly superior to days. The geographical correlations respect to timing of flowering, calculated against distances measured along simulated post-glacial migration routes, were stronger than purely latitudinal correlations. Effects of the reinvasion of Norway spruce into Finland are thus still visible in spruce populations just as they were in Scots pine populations. The proportion of the average annual heat sum needed for spruce anthesis grew rapidly north of a latitude of ca. 63° and the heat sum needed for anthesis decreased only slighty towards the timberline. In light of flowering phenology, it seems probable that the northwesterly third of Finnish Norway spruce populations are incompletely adapted to the prevailing cold climate. A moderate warming of the climate would therefore be beneficial for Norway spruce. This accords roughly with the adaptive situation in Scots pine.
  • Stewart, Erik (Helsingfors universitet, 2016)
    Heterobasidion annosum s.l. is a devastating forest pathogen species complex which causes extensive damage to timber products in northern Europe. This study examined resistance of Norway spruce (Picea abies) in two field sites in Finland to annosum root rot (Heterobasidion parviporum) utilizing non-clonal stocks of P. abies. The northern field site in Rovaniemi does not have a historical presence of the pathogen, whereas the southern field site in Lapinjärvi has extensive historical presence of the pathogen. The goals of the study were to assess potential difference in susceptibility between the sites, as well as to examine the differences in susceptibility between tissue types and organs in the trees examined. The study inoculated treatment trees with H. parviporum, as well as mock inoculations without the pathogen for control trees. Six inoculations of one treatment type were placed into each of thirty randomly selected trees at both field sites. Three inoculations were done in the stem, and three in the roots, for a total of 360 inoculations. After being left in situ for three months, the trees were harvested, and resulting lesions in the phloem and xylem tissues in both the roots and stem were measured to determine the extent of visible lesion extensions from the inoculation point. Data collected from the experiment was analyzed in the context of three mixed effects models, with the assumption that larger lesions indicated lower resistance to the pathogen. The measurements considered as response variables for the models were the total length of the lesion, total width of the lesion, and total area of the lesion. Results indicated minor overall differences in the lesion sizes between site in the lesion width and lesion area models. Significant differences were found between tissue types in the lesion width, and lesion area models. Additionally, interactions between treatment and organ, as well as treatment and tissue were significant across all models. Several other interactions were significant across some, but not all models The results indicate that further research into the potential effects of historical or geographic isolation on the resistance of P. abies to H. parviporum should include strict genetic controls with crossing of genotypes across sites, and should also consider the differences due to abiotic factors which may influence resistance in field trials.
  • Pulkkinen, Pertti (Suomen metsätieteellinen seura, 1991)
  • Greis, Ilppo; Kellomäki, Seppo (Suomen metsätieteellinen seura, 1981)
  • Kubin, Eero; Kemppainen, Lauri (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1991)
    Air and soil temperatures were measured in 1974-85 in 3 clear felled areas and 3 neighbouring forest stands dominated by Norway spruce (Picea abies) in N. Finland. Daily temperatures were measured with thermograph plotters and maximum and minimum thermometers in meteorological screens (2 m above the ground), and a Grant device at 10 cm above the ground and at 5, 50 and 100 cm below ground level. Clear felling had no significant influence on air temperature at 2 m above the ground. The daily air temperature maxima at 10 cm were greater in the clear fell area than in the forest; the daily temperature minima at 10 cm were less in the clear fell area. Night frosts were more common in the clear fell area. Daily soil temperatures at 5 cm depth were 2-3 degrees C greater in the clear fell area than in the forest; temperatures at 50 cm and 100 cm depth were 3-5 degrees C greater. A sparse sapling stand developed from plantings and natural regeneration. Consequently, the differences between the clear fell area and the forest did not diminish during the 12 years following clear felling.