Background Currently, no single biomarker can reliably identify preclinical Alzheimer’s disease (AD), particularly at or before the mild cognitive impairment (MCI) stage. Given the heterogeneity of MCI, integrative approaches are needed to improve early risk stratification. Objectives (i) To derive robust latent cognitive components from a multicenter, clinically defined MCI cohort using principal component analysis (PCA); (ii...

Legacy anthropogenic phosphorus (P) accumulated in sediments drives internal P loading in eutrophic lakes. However, predicting the temporal response of internal P loading to the external loading reduction is difficult due to the complexity of sedimentary P cycling. In this study, we use geochemical profiles obtained from a 180‐cm sediment core to constrain a reaction‐transport model and investigate the centennial‐scale respons...

Permanent phosphorus (P) burial in sediment regulates lake trophic state over long timescales, but the controls on P burial are only partially understood. A diversity of biogeochemical settings may be found in lake sediments, which may have a strong impact on the processes controlling P burial from one location to another. Here, we investigate early diagenesis of P in three contrasting lakes in Southwest Finland. Eutrophic Lak...

Biogenic varves as well as the biogenic component of clastic–biogenic varves have great potential as climate and environmental proxies but the response of biogenic lamina thickness to variations in growing-season climate is not well known. The connection of biogenic lamina thickness with growing-season or open-water season climate has been the focus of a limited number of studies. We examined biogenic laminae deposited during...

Strontium concentrations are low in fresh waters compared to seawaters. Therefore, wild‐born river‐spawning and stocked freshwater‐reared whitefish Coregonus lavaretus L. display regions with low concentrations of strontium in the centre of their otoliths. Strontium in otoliths from wild‐born river‐spawning whitefish ascending the River Tornionjoki, river‐spawning whitefish stocked as one‐summer‐old fingerlings caught ascendin...

Using biogeochemical analyses of sediments and porewaters, we investigate the legacy of a brief, intense period of eutrophication on sedimentary phosphorus (P) cycling in a boreal lake (Enonselkä basin, Lake Vesijärvi, Finland). Point-source sewage inputs in the twentieth century caused deoxygenation of the lake and accelerated the focusing of iron (Fe) and manganese (Mn) oxides into deeper areas. Early diagenesis under Fe–Mn-...

In tundra ecosystems, snow cover protects plants from low temperatures in winter and buffers temperature fluctuations in spring. Climate change may lead to reduced snowfall and earlier snowmelt, potentially exposing plants to more frequent and more severe frosts in the future. Frost can cause cell damage and, in combination with high solar irradiance, reduce the photochemical yield of photosystem II (Φ PSII ). Little is known...

Micro X‐ray fluorescence (µ‐XRF) analysis of otoliths was evaluated as a method to estimate the proportion of stocked one‐summer‐old whitefish Coregonus lavaretus L. in catches of adult fish ( n = 20) ascending the River Kemijoki to spawn. Laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) analysis was applied as control. Polished otoliths were scanned with µ‐XRF to obtain strontium maps that were used to...

The efficacy of mechanized pre-commercial thinning (PCT) done by a lightweight mini-harvester Tehojätkä together with the Chondrostereum purpureum (Pers. ex Fr.) Pouzar fungal treatment (dilutions 1:100, 1:200, 1:400) and control (cutting only) was studied for three years. The efficacy of the fungal treatment was defined as capability to prevent sprouting of birch ( Betula pendula Roth. and B. pubescens Ehrh.). The fungal trea...

Tephra from Icelandic volcanic eruptions is frequently dispersed to northern Europe, but so far tephra has not been detected in Finnish sedimentary records. We report the first finding of a cryptotephra layer in southern and central Finland. Sediment samples from five lakes and 10 peatlands, most of them located in the tephra fallout zone of the Hekla 1947 eruption, were investigated for the presence of cryptotephra to assess...

Part of the missing sink in the global CO 2 budget has been attributed to the positive effects of CO 2 fertilization and N deposition on carbon sequestration in Northern Hemisphere terrestrial ecosystems. The genus Sphagnum is one of the most important groups of plant species sequestrating carbon in temperate and northern bog ecosystems, because of the low decomposability of the dead material it produces. The effects of raised...