Quantitative elemental analysis of dry-ashed bark and wood samples of birch, spruce and pine from south-western Finland using PIXE

A total of over 200 different samples of bark and wood of Silver birch, Norway spruce and Scots pine were analysed. Samples were taken from several areas in western Finland, some with known sources of atmospheric heavy metal emission (Harjavalta, Ykspihlaja). Also analytical data for pine needles from some sites are reported. The chemical analyses were performed by thick-target particle-induced X-ray emission (PIXE) spectrometry after preconcentration by dry ashing of samples at 550oC. The following elements were quantified in most of the samples: P, S, K, Ca, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Cd, Ba and Pb. The ash percentage and the chemical composition of ashes of different wood materials were also obtained, as dry ashing was used in the analytical procedure. The variations in elemental concentrations in wood and bark of an individual tree, expressed as RSDs, were mostly in the range 10 – 20 %. For several trees of the same species sampled from small areas (< 1 ha), the variations in elemental concentrations were surprisingly high (RSDs 20 – 50 %). In the vicinity of metal plants, effects of strong atmospheric heavy metal pollution (pollution factor above 100) were observed in pine bark. The increase of heavy metal content in wood samples from the same sites was quite small. Elemental concentrations in ashes of bark and wood, from areas with no local source of atmospheric pollution, were relatively uniform. Based on this observation an alternative way of demonstrating atmospheric pollution of tree bark is discussed.

Elemental analysis of wood materials by external millibeam thick target PIXE

PIXE (Particle Induce X-ray Emission spectrometry) was used for analysing stem bark and stem wood of Scots pine, Norway spruce and Silver birch. Thick samples were irradiated, in laboratory atmosphere, with 3 MeV protons and the beam current was measured indirectly using a photo multiplicator (PM) tube. Both point scans and bulk analyses were performed with the 1 mm diameter proton beam. In bulk analyses, whole bark and sectors of discs of the stem wood were dry ashed at 550 ˚C. The ashes were homogenised by shaking and prepared to target pellets for PIXE analyses. This procedure generated representative samples to be analysed, but the enrichment also enabled quantification of some additional trace elements. The ash contents obtained as a product of the sample preparation procedure also showed to be of great importance in the evaluation of results in environmental studies. Spot scans from the pith of pine wood outwards, showed clearly highest concentrations of manganese, calcium and zinc in the first spot irradiated, or 2-3 times higher than in the surrounding wood. For stem wood from the crown part of a pine this higher concentration level was found in the first four spots/mms, including the pith and the two following growth rings. Zinc showed increasing concentrations outwards in sapwood of the pine stem, with the over-all lowest concentrations in the inner half of the sapwood. This could indicate emigration of this element from sapwood being under transformation to heartwood. Point scans across sapwood of pine and spruce showed more distinct variations in concentrations relative to hearth wood. Higher concentrations of e.g. zinc, calcium and manganese were found in earlywood than in denser latewood. Very high concentrations of iron and copper were also seen for some earlywood increments. The ash content of stem bark is up to and order higher than for the stem wood. However, when the elemental concentration in ashes of bark and wood of the same disc were compared, these are very similar – this when trees are growing at spots with no anthropogenic contamination from the atmosphere. The largest difference was obtained for calcium which appeared at two times high concentrations in ashes of bark than in ashes of the wood (ratio of 2). Pine bark is often used in monitoring of atmospheric pollution, where concentrations in bark samples are compared. Here an alternative approach is suggested: Bark and the underlying stem wood of a pine trees are dry ashed and analysed. The elemental concentration in the bark ash is then compared to the concentration of the same element in the wood ash. Comparing bark to wood includes a normalisation for the varying availability of an element from the soil at different sites. When this comparison is done for the ashes of the materials, a normalisation is also obtained for the general and locally different enrichment of inorganic elements from wood to bark. Already a ratio >2 between the concentration in the bark ash and the concentration in the wood ash could indicate atmospheric pollution. For monitoring where bark is used, this way of “inwards” comparison is suggested - instead of comparing to results from analyses of bark from other trees (read reference areas), growing at sites with different soil and, locally, different climate conditions. This approach also enables evaluation of atmospheric pollution from sampling of only relative few individual trees –preferable during forest felling.

Mänskoblivandets läggspel : en tematisk analys av kvinnan och tiden i Solveig von Schoultz poesi

Solveig von Schoultz (1907–1996) hör till de betydande i svensk poesi – doktorsavhandlingen är den första som behandlar hennes diktarskap. Som lyriker engagerades hon av livets stora frågor, sådana de föds ur den konkreta erfarenheten. Hennes känsla för det individuella rymde ett vidare perspektiv, en enveten drivkraft att förstå tillvarons dolda sammanhang. I avhandlingen görs en tematisk analys av kvinnan och tiden som en process av människoblivande i von Schoultz poesi. Genom textnära läsningar och motiviska studier diskuteras temat kvinna – människa i dess mångfaldiga yttringar. Även om innehåll och idéer har en stor tyngd i von Schoultz poesi är hon ytterst medveten och noggrann gällande formen. Det handlar inte bara om vad man säger utan hur, betonade hon. I avhandlingen fästs därför avseende vid form såväl som innehåll. Centrala begrepp i analyserna är identitet, moderskap och arbete, kring vilka avhandlingen byggs upp. Diktanalyserna visar hur tematiken förvandlas och består i det långa diktarskapet och ger en bild av von Schoultz värdegrund och djupa humanism.

Åtgärdsprogram för vattenvården i Nyland för åren 2016 – 2021

Åtgärdsprogrammet för vattenvården i Nyland innehåller uppgifter om vattnens status samt om de åtgärder som krävs för att förbättra och upprätthålla yt- och grundvattnens status under förvaltningsperioden 2016 – 2021. Ytvattnens ekologiska status i är svag i synnerhet på de åkerdominerade avrinningsområdena och i Finska vikens kustvatten. Åarnas och älvarnas status försämras särskilt av eutrofiering till följd av diffus belastning, men också av byggande, reglering och uppdämning. Ytvattnens kemiska status i Nyland har till stor del bedömts vara god. Den sämre än goda kemiska statusen beror i huvudsak på de kvicksilverhalter i abborre som överstiger miljökvalitetsnormen. I Nyland finns 21 grundvattenområden som fastställts ha dålig kemisk status. De vanligaste orsakerna till att den kemiska statu-sen försämrats är grundvattnets kloridhalt, lösningsmedel, bekämpningsmedel samt bensintillsatsen MTBE. De sammanlagda kostnaderna för de åtgärder som föreslås i åtgärdsprogrammet är 372 miljoner euro per år. Härav är 351 mil-joner euro grund- och andra åtgärder som ska vidtas med stöd av annan lagstiftning och 20 miljoner euro åtgärder som kom-pletterar vattenvården. Lagstiftningsbaserade, ekonomiska, förvaltningsmässiga och informationsmässiga styrmetoder har presenterats för att främja genomförandet av åtgärderna. Ansvarsområdena och samarbetsparterna för genomförandet av styr-metoderna har fastställts.