Seasonal and Diurnal Variations in Atmospheric and Soil Air 14CO2 in a Boreal Scots Pine Forest

We present a radiocarbon (C-14) dataset of tropospheric air CO2 forest soil air CO2, and soil CO2 emissions over the course of one growing season in a Scots pine forest in southern Finland. The CO2 collection for C-14 accelerator mass spectrometry (AMS) analysis was done with a portable, suitcase-sized system, using molecular sieve cartridges to selectively trap CO2 The piloting measurements aimed to quantify the spatial, seasonal and diurnal changes in the C-14 content of CO2 in a northern forest site. The atmospheric samples collected above the canopy showed a large seasonal variation and an 11 parts per thousand difference between day and nighttime profiles in August. The higher Delta C-14 values during night are partly explained by a higher contribution of C-14-elevated soil CO2, accumulating in the nocturnal boundary layer when vertical mixing is weak. We observed significant seasonal trends in Delta C-14-CO2 at different soil depths that reflected changes in the shares of autotrophic and heterotrophic respiration. Also the observed diurnal variation in the Delta C-14 values in soil CO2 highlighted the changes in the origin of CO2, with root activity decreasing more for the night than decomposition.Peer reviewe

The differences in carbon dynamics between boreal dwarf shrubs and Scots pine seedlings in a microcosm study

Peer reviewe

Annual cycle of Scots pine photosynthesis

Photosynthesis, i.e. the assimilation of atmospheric carbon to organic molecules with the help of solar energy, is a fundamental and well-understood process. Here, we connect theoretically the fundamental concepts affecting C-3 photosynthesis with the main environmental drivers (ambient temperature and solar light intensity), using six axioms based on physiological and physical knowledge, and yield straightforward and simple mathematical equations. The light and carbon reactions in photosynthesis are based on the coherent operation of the photosynthetic machinery, which is formed of a complicated chain of enzymes, membrane pumps and pigments. A powerful biochemical regulation system has emerged through evolution to match photosynthesis with the annual cycle of solar light and temperature. The action of the biochemical regulation system generates the annual cycle of photosynthesis and emergent properties, the state of the photosynthetic machinery and the efficiency of photosynthesis. The state and the efficiency of the photosynthetic machinery is dynamically changing due to biosynthesis and decomposition of the molecules. The mathematical analysis of the system, defined by the very fundamental concepts and axioms, resulted in exact predictions of the behaviour of daily and annual patterns in photosynthesis. We tested the predictions with extensive field measurements of Scots pine (Pinus sylvestris L.) photosynthesis on a branch scale in northern Finland. Our theory gained strong support through rigorous testing.Peer reviewe

Environmental control of growth variation in a boreal Scots pine stand : a data-driven approach

Peer reviewe

Comparing ecosystem and soil respiration : Review and key challenges of tower-based and soil measurements

The net ecosystem exchange (NEE) is the difference between ecosystem CO2 assimilation and CO2 losses to the atmosphere. Ecosystem respiration (R-eco), the efflux of CO2 from the ecosystem to the atmosphere, includes the soil-to-atmosphere carbon flux (i.e., soil respiration; R-soil) and aboveground plant respiration. Therefore, R-soil is a fraction of R-eco and theoretically has to be smaller than R-eco at daily, seasonal, and annual scales. However, several studies estimating R-eco with the eddy covariance technique and measuring R-soll within the footprint of the tower have reported higher R-soil than R-eco, at different time scales. Here, we compare four different and contrasting ecosystems (from forest to grasslands, and from boreal to semiarid) to test if measurements of R-eco are consistently higher than R-soil. In general, both fluxes showed similar temporal patterns, but R-eco, was not consistently higher than R-soil from daily to annual scales across sites. We identified several issues that apply for measuring NEE and measuring/upscaling R-soil that could result in an underestimation of R-eco and/or an overestimation of R-soil. These issues are discussed based on (a) nighttime measurements of NEE, (b) R-soil measurements, and (c) the interpretation of the functional relationships of these fluxes with temperature (i.e., Q(10)). We highlight that there is still a need for better integration of R-soil with eddy covariance measurements to address challenges related to the spatial and temporal variability of R-eco, and R-soil.Peer reviewe

Distinct patterns of below- and aboveground growth phenology and litter carbon inputs along a boreal site type gradient

Forest ecosystem productivity is strongly linked to site nutrient availability, which is influenced by litter inputs and their decomposition rates. Fine roots and mycelia are key contributors in belowground soil carbon (C) accumulation, but studies have seldom reported how belowground litter C input is related to site types in boreal forests. In this study, three mature and one young Pinus sylvestris forests along a site type gradient in southern Finland were chosen for measurements of fine root biomass, fine root longevity, below- and aboveground growth phenology and annual litter input from tree and understorey vegetation. Site types were distinguished by understorey vegetation composition, which indicated the site fertility. Fine root biomass per tree stand basal area decreased significantly from nutrient-poor to nutrient-rich sites, the nutrient-poor sites with longer fine root longevity resulted in an equal belowground litter input with the nutrient-rich site. Above- and belowground annual litter inputs were 131–236 and 70–91 g m−2 year−1, respectively. Aboveground litter increased with site fertility, resulting into belowground litter having a decreasing trend from 37% to 23% of total litter inputs with increasing site fertility. Ectomycorrhizal mycelia and understory production contributed 8–13% and 18–41% of belowground production, respectively. Contribution of understorey vegetation to the belowground litter C input was lower than that of trees at xeric and sub-xeric sites but equaled to that of trees at the mesic site. Our study showed distinct dimensions of below- and aboveground litter inputs influenced by site types. Moreover, we emphasize that the belowground C inputs from ectomycorrhizal mycelia and the understorey in addition to those of trees should always be considered in C balances and C reporting in boreal conifers.Peer reviewe

Työelämän kehittäminen kolmikantaisessa yhteistyössä : TYÖ2030-ohjelma

Työmarkkinoilla on 2020-luvun alussa eletty työn ja teknologian murrosta, jota koronapandemia ja sota Ukrainassa ovat osaltaan vauhdittaneet. Työyhteisöjä, organisaatioita sekä niiden kykyä sopeutua ja uudistua on haastettu voimakkaasti ja myös uusilla tavoilla. Koko suomalaisen hyvinvointiyhteiskunnan säilymisen ja uudistumisen kannalta on ratkaisevaa, miten työyhteisöt, organisaatiot ja niiden muodostamat verkostot onnistuvat omassa kehittämis- ja uudistamistyössään. Suomessa on pitkä perinne laajaan yhteistyöhön perustuvasta ohjelmallisesta työelämän kehittämisestä. Työelämän ohjelmallisen kehittämisen tavoitteena on edistää työn tuloksellisuuden ja työelämän laadun kehittymistä suuressa joukossa työyhteisöjä ja työorganisaatioita, vastata niiden kehittämistarpeisiin sekä tukea niiden omaa kehittämisosaamista ja oppimista toistensa kokemuksista. Tässä katsauksessa kuvataan suomalaisen työelämän erityispiirteitä, ohjelmallisen kehittämisen historiaa sekä käynnissä olevan hallituskauden 2019–2023 ohjelmatyötä. Katsauksessa keskitytään erityisesti TYÖ2030- eli Työn ja työhyvinvoinnin kehittämisohjelman kuvaamiseen

Work life development in tripartite co-operation : The WORK2030 programme

In the early 2020s, the Finnish labour market has been undergoing a significant technology and work transformation accelerated by the COVID-19 pandemic and the war in Ukraine. Work communities, organizations and their ability to adapt and update themselves have been tested thoroughly, also in new ways. In order for the entire Finnish welfare state to survive and reform, it is essential that work communities, organizations and the networks formed by them succeed in their development and reform work. Finland has a long tradition in programmatic work life development based on co-operation. The goal of programmatic work life development is to promote improvements in performance and quality of work life and quality of work life in a large group of work communities and organizations, meet their development needs and support their own development competence and learning from each other’s experiences. This review describes the special characteristics of Finnish work life, the history of programmatic development and the programme work during the current parliamentary term of 2019–2023. The review focuses particularly on the description of the Work and Well-being at Work Development Programme (WORK2030)