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CO2 Fluxes: Measurements and Modelling in the Changing Arctic Critical Zone
No full textIn terrestrial ecosystems, biotic and abiotic components are interconnected and respond to environmental and climate pressures. The tundra is the life support system of Arctic ecosystems, but it is exposed to climate change. Its frozen soil, a major carbon stock, is affected by temperature rise. It is therefore important to understand its functioning and dynamics, in particular regarding the carbon cycle. For this purpose, we established the first High Arctic “Critical Zone” observatory in the Bayelva basin in Svalbard (NO).The term Critical Zone (CZ) means the “heterogeneous, near surface environment in which complex interactions involving rock, soil, water, air, and living organisms regulate the habitat and determine the availability of life-sustaining resources” (Giardino and Houser 2015). In its approach, biotic and abiotic interactions are seen as a continuum, which demand scientists to overcome the partition between disciplines. Hence, chemistry, biology, physics, and geology must be used together to interpret a complex system where living and non-living components are interconnected.In the Bayelva Critical Zone Observatory, we investigate the CO2 fluxes between soil, vegetation and atmosphere. Since the Holocene, the High Arctic soil has been slowly but consantly acting as a carbon sink, despite the little primary productivity (GPP), as the low temperatures and the scarce presence of grazers and decomposers have limited decomposition and ecosystem respiration (ER). With the temperatures rise, however, such processes are rapidly changing, but the direction of change is still uncertain. In fact, the multiple factors of change are acting on both GPP and ER: due to the thawing permafrost, more organic matter is available in the active layer for bacterial decomposition, whose metabolism is enhanced by temperature rise. At the same time, the widening of the snow-free season and vegetation composition shifts may cause an increase of carbon uptake. On top of this, climatic and environmental factors as soil moisture, topography, vegetation cover, can influence GPP and ER at the local scale, modulating the spatial variability.To understand the trends in future balance between GPP and ER, it is necessary to identify their primary drivers and model their contribution to CO2 fluxes. As the tundra is heterogenous, the spatial scale and representativeness are important factors to take into account.To this aim, we measure and model CO2 fluxes at the soil-vegetation-atmosphere interface at several scales, using flux chambers, Eddy Covariance and remote sensing data.In the High Arctic, the flux chamber method is particularly suitable to assess ecosystem variability at fine scale Figs 1, 2. Moreover, it allows to directly measure ecosystem respiration by shading the chamber, and the low air temperatures and irradiance reduce the chamber disturbance during the measurement. Its use allowed us to investigate CO2 fluxes as a function of soil moisture and temperature and vegetation cover, as well as investigating CO2 fluxes at both plot scale and at single species level.We conducted five field campaigns since 2019, over three areas differing for aspect, vegetation density, species composition, and age of deglaciation. Surveys were conducted during the vegetative peak season (mid July, with shifts modulated by the date of snowmelt). At each site, at least 20 single point measurement per day of NEE and of ER were taken, together with the recording of solar irradiance, air temperature and moisture (Fig. 3), soil temperature and volumetric water content, and taking RGB pictures of the vegetation cover to extract the green fractional cover (Fig. 4) (around 2,000 single point measurements). We then built empirical models describing CO2 fluxes as a function of the most relevant drivers. A non-linear model was built by taking Solar Irradiance and Soil Temperatures as main drivers of respectively GPP and ER (Lloyd and Taylor 1994, Ruimy et al. 1995), and the other drivers as local perturbations of the classic equations. Linear models were also calculated, with the only constrain to include Solar Irradiance and Temperature. We thus explored the ecosystem response in terms of interannual, spatial, and species-specific variability, speculating on the possibility to extent the models use in space and time.Overall, our results may have relevant implications on modelling carbon fluxes in the tundra at larger scale. At present, vegetation models used in global climate models operate only at a large scale (10 – 100 km), while small scale variability is not taken into account. In addition, they are affected by large uncertainties that need to be reduced to properly predict the changes in CO2 budget. Deriving new, small-scale models based on measured data can help bridging the gap between the large-scale climate-vegetation models and the reality of carbon exchanges.Another source of uncertainty in the Arctic carbon budget comes from winter fluxes. Recent studies revealed that biological activity is present under the snow cover, as soil respiration occurs at temperatures below zero. Eddy covariance (EC) also revealed low positive fluxes during the snow-covered season. Howewer, accurate quantification of the fluxes from snowpack by means of EC is hampered by the buffering effect of the snow pores, and by the sudden release of the CO2 trapped in the snow during wind guts, when horizontal advection is dominant. To overcome such difficulties, we are measuring CO2 emissions from the snowpack using a different approach, based on an array of CO2 sensors embedded in the snowpack (Fig. 5), where the flux is calculated using the Fick’s law of diffusion in a porous medium. In our presentation, we will give an overview of the results obtained so far
Socioecological metabolism: investigating sustainability across scales
No full textSustainability challenges are related to socioecological interactions occurring on various spatial and temporal scales. Processes on different scales are linked, hence place- or site-based research – such as many LT(S)ER approaches – needs embedding in larger, often global contexts. This is even more relevant today, as rising geopolitical tensions, international conflicts and wars, pandemics and increasingly frequent and severe impacts of climate heating drive the world towards a multipolar ‘divided world’ scenario.Socioecological metabolism (SEM) is an increasingly widespread and powerful approach to study societies’ material basis. SEM is focused on societies’ use of biophysical resources (materials, energy or land) in production and consumption processes that underly delivery of services essential for social wellbeing (e.g., shelter, nutrition, mobility, education, healthcare, hygiene and many more). In the process, societies accumulate ‘material stocks’ in buildings, infrastructures, machinery or other artefacts, in addition to the bodies of humans and livestock belonging to any specific society. Delivery of services requires specific combinations of material stocks and energy or material flows (the ‘stock-flow-service nexus’). At the same time, patterns of societal material stocks shape practices of dwelling, being mobile, nourishing oneself and so on that are intimately interrelated with patterns and levels of resource use, thereby shaping (un)sustainability (the ‘stock-flow-practice nexus’).SEM is directly and indirectly related to ecological impacts at all stages, from extraction to accumulation of stocks and outflows of wastes and emissions. For example, biomass extraction affects roughly three quarters of the earth’s lands (except Antarctica and Greenland), thereby contributing to the global land squeeze and to pressures on biodiversity. Built structures (buildings and infrastructures), while occupying a relatively small proportion of earth’s land surface, structure landscapes and have far-reaching ecological consequences, e.g. by restricting movement of species or opening pristine regions for development. Outflows of wastes and emissions, among others, drive global heating, which again affects ecosystems across all scales.In this presentation, I will review the current state-of-the-art in terms of quantifying and modelling socioecological metabolism and studying its relations with societies and their economies. In addition to highlighting some current highly granular (up to 10m spatial resolution nation-wide, 90m global) and long-term (>100 years) quantifications of stocks and flows in SEM, I will discuss current progress in linking SEM data with social wellbeing and achievement of decent living standards. I will also provide an outlook to ongoing research aiming at a better understanding of the effects of disruptions on SEM and its wellbeing contributions. Given that current SEM methods are only descriptive, static or at best represent linear dynamics, this will involve integration with models from complexity science that can grasp the non-linear dynamics of networked systems (tipping points, phase transitions, etc.). Efforts are also under way to harness the power of the emerging highly granular SEM data and models for transformative research by linking them with actors, institutions and power relations to investigate the malleability of social metabolism.This recent and ongoing research aims to provide a robust basis for integrating social sciences and natural sciences when studying the sustainability of globally embedded socio-ecological systems. The SEM approach hence can crucially contribute to integrating local, actor-centered and participatory research into larger-scale models and assessments
Morphological and phylogenetic analysis reveal three new species Phyllosticta (Phyllostictaceae, Botryosphaeriales) in China
No full textPhyllosticta (Phyllostictaceae, Botryosphaeriales) species have been reported worldwide and collected from various plant hosts. We proposed three new species, viz., Phyllosticta elliptica sp. nov., P. rhododendri sp. nov., and P. wuzhishanensis sp. nov., based on multi-locus phylogenetic analysis using a combined dataset of ITS rDNA, LSU, tef1, ACT, and GPDH, along with morphological characteristics. Moreover, P. capitalensis, isolated from the leaves of Mangifera indica, is redescribed herein. We have re-examined the six species complexes: the P. capitalensis species complex (including 32 species), P. concentrica species complex (including 32 species), P. cruenta species complex (including 22 species), P. owaniana species complex (including six species), P. rhodorae species complex (including two species), and P. vaccinii species complex (including two species). Detailed descriptions and illustrations of the new species are provided. These findings enrich the biodiversity of fungi and provide reference for subsequent research
A long-term monitoring dataset of waterbirds at Lake Miedwie, Poland (2002–2025)
No full textLake Miedwie, located in northwestern Poland, is one of the most important wetland areas for non-breeding waterbirds in the region. Recognised as both an Important Bird Area (IBA) and part of the Natura 2000 network, the site supports large numbers of migratory and overwintering geese, ducks, and other waterbirds. Since 2002, standardised surveys have been conducted during the non-breeding season to monitor population sizes and species composition. The site’s location on major flyways and its habitat diversity make it valuable for long-term ornithological monitoring.This dataset presents waterbird count data collected during the non-breeding season from 2002/2003 to 2024/2025, covering 23 seasons across 24 calendar years. The dataset includes 952 records of seasonal abundance for 14 key waterbird species. The average total abundance was 7,933 (± 1,314 SE) individuals per season (mean of November, January, and March), with a high of 36,095 in November 2002 and a low of 226 in March 2017. Trend analysis using the rtrim (Trends and Indices for Monitoring Data) package in R indicated a moderate overall decline (λ = 0.9758, 95% CI: [0.9750 – 0.9766]). Species-specific trends varied, with some taxa, such as Greylag Goose (Anser anser Linnaeus, 1758), increasing, while others, including Greater White-fronted Goose (Anser albifrons Scopoli, 1769), Eurasian Teal (Anas crecca Linnaeus, 1758), and Eurasian Coot (Fulica atra Linnaeus, 1758), declined. The dataset contributes valuable baseline data for wetland bird conservation, ecological assessment, and future research in Central Europe. Importantly, such long-term monitoring also provides a robust reference point for assessing changes in climate and biodiversity over time
Notulae to the Italian flora of algae, bryophytes, fungi and lichens: 19
No full textIn this contribution, new data concerning algae, bryophytes, fungi and lichens of the Italian flora are presented. It includes new records, confirmations or exclusions for the algal genera Cladophoropsis, the bryophyte genera Bryum, Cinclidotus, Dicranella, and Pulvigera, the fungal genera Ascocoryne, Calycina, Echinoderma, Hohenbuehelia, Laccaria, Lasiosphaeria, Leucocoprinus, Neodasyscypha, Propolis, Psathyrella, and Sclerococcum, and the lichen genera Acarospora, Bryoplaca, Caloplaca, Candelariella, Catapyrenium, Cladonia, Lecanora, Lepra, Monerolechia, Mycobilimbia, Pertusaria, Pycnora, Spilonema, Thelopsis, and Xylopsora
Hemi-boreal forest ecosystem under the pressures of global environmental changes
No full textEcological and socioeconomic importance of the forest ecosystems is recently becoming of increased concern due to their damages caused by direct effect of climate change and air pollution and their indirect threats, including insect and disease infestation, fragmentation, fire, invasive species and etc. The UNECE Integrated Monitoring Programme, which has been performed since 1994 in Lithuania, provides all the necessary data for solving this problem. Aukstaitija Integrated monitoring station which is included in the eLTER network creates the Long-term forest ecosystem monitoring and modeling platform to meet the recent challenges related to sustainable development of the hemi-boreal forest. 30 years changes in environmental conditions revealed that implementation of international legislation in the area of transboundary air pollution reduction resulted in higher than tenfold reduction of air concentrations of sulphur compounds and their deposition at regional polluted areas between 1994 and 2024. In 2021 and 2022, when precipitation exceeded the value of long term average, sulphur concentration in soil and ground water at Lithuanian Integrated monitoring stations (LT-01 and LT-03) reached the lowest values during whole period of investigation, i.e. by about 0.5 mg/l, and 5 mg/l respectively, following the lowest 7.6 pH values in surface water during the entire study period (Algirdas et al. 2015). These changes in acidifying components promote the regeneration of tree condition expressed by reduction in tree crown defoliation, which occurs most intensively in coniferous tree species.Climate change during the considered period was expressed through the increase in temperature and precipitation amount by 0.05 ˚C per year and 1.35 mm per year respectively. The most significant increase in temperature was recorded in 2024 when mean temperature exceeded 9.0 °C, which was the highest value during the whole period of meteorological investigation (Algirdas et al. 2018). Such increase resulted in outbreaks of Ips typographus damages in mature spruce forest. Therefore, new meteorological threats for forest ecosystems in Lithuania could be hot and dry periods from April up to June. Contrary to that gradual increase in precipitation amount resulted in increase in soil humidity and recovery of the ground water level which resulted in better crown condition and higher annual increment of prevailing in hemi-boreal forest tree species. Only due to damages caused by Ips typographus after drought and heat wave Norway spruce trees crown condition deteriorated significantly. Notwithstanding this the heavy rainfall in 2021-2022 raised the groundwater level, especially during the vegetation period, which could be described as the beginning of the restoration of the geosystem's water resources and regeneration of forest condition.Climate and air pollution changes also resulted in higher annual litterfall production and decrease in mean defoliation at considered sites following by higher tree annual increment (Algirdas et al. 2018; Marius et al. 2021). These changes indicated that increase in litterfall by 100 kg per ha per year results in decrease in crown defoliation by about 0.2 % per year.Chemical analysis of foliage samples of the dominant tree species revealed that, N, K, Ca and especially Fe concentrations significantly increased. Macro and micro elements P, Mn, Mg and Al tended to decrease or remained at a stable level. These changes increase the resistance of the main tree species to unfavorable environmental factors primarily diseases and pests, which is especially important for spruce trees.Correlation analysis of litter and average defoliation and precipitation amount showed that increasing precipitation and rising average temperature increase litter formation, but very slightly and insignificantly. Precipitation also has no significant effect on the change in tree canopy defoliation, while rising air temperature has a positive effect on tree canopy formation, increasing canopy density and foliage amount, which also increases the amount of litter falling on the soil surface. Significantly decreasing air pollution with acidifying components and their concentrations in precipitation and flows with precipitation also have a positive effect on litter formation, reduction in crown defoliation and increasing the productivity of hemi-boreal forest ecosystem.Finally, results obtained in the Aukštaitija and Žemaitija IMS basins revealed that the state of forest ecosystems should improve and resistance to adverse environmental factors, diseases and pests increase. Additionally obtained data revealed that in a forested area, not only does climate warming occur at a lower intensity than in an open non-afforested area, but also the amount of precipitation there is significantly higher. This is the effect of forests on the climate change-mitigation process
Introducing the Optical Gas Exchange System (OGES) concept
No full textField and long-term measurements of leaf-level photosynthetic gas exchange have been pivotal to understand and model the environmental regulation of leaf photosynthesis (Hari and Makela 2003). Now, scientists seek for means to understand and model the environmental regulation of planetary photosynthesis, by means of remotely sensed data. In addition to gas exchange, photosynthesis generates multiple optical clues that are embedded in the intensity and spectral properties of the light reflected or emitted via chlorophyll fluorescence (ChlF) by vegetation. These signals can be recorded with optical sensors and nowadays measured across a continuum of scales: from leaves to entire ecosystems (Porcar-Castell et al. 2021). However, we are still missing the mechanistic understanding that is required to fully exploit the potential of these data, largely due to the lack of concomitant and long-term observations of photosynthetic gas exchange and optical signals at the scale of a leaf, the smallest scale at which they can be measured in vivo. The Optical Gas Exchange System (OGES) aims at filling this gap by providing field and long-term measurements of photosynthetic gas exchange, pulse amplitude modulated (PAM) chlorophyll fluorescence, and leaf spectral reflectance. By doing so, the OGES provides both a comprehensive view of the photosynthetic regulation (both from the light and carbon reactions point of view) (Oivukkamäki et al. 2024), as well as a unique dataset to disentangle the connection between optical and photosynthetic dynamics and their environmental and physiological regulation. In this communication we present preliminary results from the OGES system tests conducted in the Station for Measuring Ecosystem-Atmosphere Relations (SMEAR) II in Hyytiälä during summer 2023 and 2024. Data integrates observations from a µPAM system (Walz GmbH, Germany) to detect ChlF and track the acclimation of the light reactions, an OctoFLOX spectrometer system (JB Hyperspectral, Germany) and the existing gas exchange measurements in SMEAR-II Station in Hyytiälä, which can resolve shoot-level dynamics of CO2, H2O or VOC fluxes. In addition, nocturnal LED-induced Fluorescence (LEDIF) methods (Atherton et al. 2019) are being developed for added versatility and information content. Preliminary results indicate that it is possible to automatically record the temporal variations in leaf reflectance and fluorescence spectra under field conditions. Implications, following steps and challenges are discussed. A first concept version demonstrating the potential of integrated long-term µPAM and gas exchange measurements is described in Oivukkamäki et al. (2024)
Collaborative Soil Health Assessment: Integrating Citizen and Scientist Perspectives
No full textOver 60% of European soils are considered unhealthy, which clearly calls for a transformation towards sustainable soil management. Taking care of our soils is imperative, since they are key components of our ecosystems and provide up to 99% of our food. Agricultural long-term field experiments (LTEs) are key to understanding how different agroecological practices affect the soil and have existed since the 1850s in Europe and beyond. LTEs can be seen as core sites that allow researchers extended measurements and monitoring of the trends and change and enable policy makers to gain a deeper understanding into soils, especially in times of climate change. However, they alone will not be able to transform the public perception of soil health and give reasons to protect and enhance soil health. Participatory citizen science is a research method that actively involves and engages the public in hands-on scientific enquiry to generate new knowledge or understanding. Most of the soil citizen science projects so far have been focusing on biodiversity, a weak point in European soil monitoring. Thus, actively engaged citizens could help to evolve our knowledge about the most appropriate field soil health indicators to test the effectiveness of different potentially sustainable soil management practices. This presentation will highlight a transdisciplinary effort from citizens and scientists in assessing soil health at a case study area in the Marchfeld in eastern Austria. We will highlight how soil biological, chemical and physical properties - key aspects of soil health - can be measured by both citizens and researchers, to assess soil health for maintaining fertile soils for future generations and ensuring ongoing food production. Promoting co-creation, fostering knowledge-sharing networks and enabling long-term communication and commitment with citizens will be highlighted as success factors for continuing transdisciplinary cooperation among diverse soil health stakeholders
Predictive value of neutrophil-lymphocyte ratio and platelet-lymphocyte ratio in patients with vaginitis: nested case-control study
No full textAim: To investigate the value of the hematological indices to differentiate bacterial vaginosis (BV) from vulvovaginal candidiasis (VVC) and predict treatment response. Materials and methods: This nested case-control study included 390 women divided into three groups: healthy women, women diagnosed with BV, and women diagnosed with VVC. Additionally, two groups (BV and VVC) were treated and followed prospectively until cured. Demographic data, blood indices, and high-sensitivity C-reactive protein (hsCRP) were obtained from the women. Results: hsCRP and neutrophil-lymphocyte ratio (NLR) showed the best diagnostic utility to predict BV with AUC=0.721 and 0.735, respectively. hsCRP showed the best specificity (99.23%), while NLR showed the best sensitivity (82.31%) to differentiate BV. Regarding percentage change after treatment, NLR showed a higher reduction percentage in the BV group (−27.41±8.151%) than VVC (0.158±5.804%). Conclusions: NLR is an efficient diagnostic instrument for distinguishing individuals with bacterial vaginosis from those with vulvovaginal candidiasis. Its diagnostic reliability is comparable to more regularly used markers such as WBC and hsCRP. Both NLR and PLR are good predictors of clinical response to treatment in bacterial vaginosis
Giant vulvar polyp in a postmenopausal woman: a rare clinical case
No full textThe increased frequency of precancerous lesions and malignant diseases of the vulva is a hallmark of the postmenopausal period. However, the development of fibroepithelial polyps, which are benign neoplasms, is also possible. The exact etiology and pathogenesis remain unclear. These mesenchymal neoplasms are mostly diagnosed in women who received hormone replacement therapy or those who are of reproductive age, with pregnancy being a predisposing factor. We present a clinical case in which surgical treatment was the first choice, and histopathological examination confirmed the diagnosis. The authors report a case of a postmenopausal patient not taking hormone replacement therapy with a single, large, benign, pedunculated fibroepithelial polyp of the vulva (more than 5 cm long) that appeared more than 15 years ago. The polyp was successfully excised, with a good prognosis for the patient. This clinical case emphasizes the accurate clinical diagnosis and the importance of histopathological examination. It illustrates delayed help-seeking in the absence of mandatory prophylaxis