Central-eastern Finland Research Articles

Variations in near-saturated hydraulic conductivity of arable mineral topsoils in south-western and central-eastern Finland

Soil hydraulic properties play an important role in determining the level of crop productivity and the extent of environmental loading. Consequently, measurement of near-saturated soil hydraulic conductivity (K(h)) by tension infiltrometer (TI) is an interesting technique. To provide reference values for near-saturated K(h) in arable mineral topsoils of Finland and to investigate variability in these values caused by tillage, antecedent soil moisture content and earthworm burrows, field measurements were conducted in south-western and central-eastern Finland using the TI technique, at supply pressure head –6, –3, and –1 cm. The range of near-saturated K(h) values obtained was 0.02–12.6 mm h-1 at –6 cm, 0.30–85.9 mm h-1 at –3 cm, and 2.55–250 mm h-1 at –1 cm. At –6 cm pressure head, clay soils tended to show lower values than coarser-structured soils, but the order was reversed at –1 cm. The spatial variation in near-saturated K(h) was moderate and was exceeded by the temporal variation.

Eutrophication histories of three contrasting lakes in a naturally nutrient-rich boreal watercourse

The Iisalmi Route watercourse in central-eastern Finland contains a number of highly eutrophic lakes. Despite substantial impacts from anthropogenic activity, the region appears to be naturally eutrophic because of its geological setting. A passive continental ice sheet deposited fine-grained basal till that contributes to the naturally eutrophic status of the lakes. Detailed paleolimnological studies in the Iisalmi Route are few. Therefore, we studied the eutrophication histories of three contrasting Iisalmi Route lakes: (1) small headwater Lake Saarisjarvi, (2) larger, but very shallow headwater Lake Nalantojarvi, and (3) large central basin, Lake Porovesi. We compared the suitability of three diatom-total phosphorus transfer functions for application to fossil samples. A local transfer function, specifically targeted to the Iisalmi Route, was the most suitable for the headwater lakes. In contrast, two regional transfer functions, which have larger geographical coverage, performed equally well for the large central basin. All three lakes proved to have been naturally eutrophic for thousands of years. Highest natural variability occurred in the longest core, from shallow headwater Lake Nalantojarvi. This variability reflects the dynamic development of the basin and its catchment after deglaciation. Diatom assemblage changes in cores from Lakes Saarisjarvi and Porovesi suggest cultural eutrophication, most likely after the region was colonized in the sixteenth century, followed by salinization in more recent times. Our study deepens understanding of naturally eutrophic boreal lakes that are located on fine-grained tills and their sensitivity to natural and anthropogenic forcing. Our results also highlight the importance of selecting appropriate transfer functions and realistic restoration targets when dealing with naturally eutrophic lakes.

Quaternary Landforms and Basin Morphology Control the Natural Eutrophy of Boreal Lakes and Their Sensitivity to Anthropogenic Forcing

Both natural and anthropogenic changes in boreal lakes have been studied utilizing paleolimnological methods, but the spatial variation in the natural conditions of lakes and its connection to geological factors has drawn less attention. Our aims were to examine the spatial distribution of naturally eutrophic lakes on the previously glaciated terrain of central-eastern Finland and the relationship between pre-human disturbance water quality and geological factors related to the basins and their catchments. Furthermore, we studied the pre- to post-human disturbance changes in the diatom assemblages and water quality of 48 lakes (51 sampling sites) across the pre-disturbance phosphorus gradient by using the top-bottom sampling approach and multivariate statistics. According to our results, naturally eutrophic boreal lakes are more common than previously thought, occurring on fine-grained and organic Quaternary landforms, including fine-grained till. Our study emphasizes the importance of the previously overlooked matter of till grain-size variation as a driver behind the spatial variation in the natural trophic states of boreal lakes. The location of a lake in the hydrologic landscape and basin morphology appear to be important factors as well. Shallow, naturally eutrophic lakes with short water residence times and high catchment area to lake area and volume ratios have been particularly sensitive to anthropogenic forcing. Our results indicate that cultural eutrophication is not the only water protection challenge for the relatively remote and dilute boreal lakes, but salinization and alkalinization are also serious threats that should be taken into account. Therefore, it is crucial to consider the notable variation in the natural conditions of boreal lakes in addition to mitigating the effects of anthropogenic forcing, such as nutrient loading, catchment erosion, salt pollution, and climate change, in order to achieve efficient water protection.

Dietary patterns are associated with the prevalence of alexithymia.

Recent evidence supports the association between healthy dietary patterns and a reduced risk of depression. The objective was: (1) to examine the associations between dietary patterns and alexithymic features; and (2) investigate whether these possible associations are explained by depressive symptoms in a cross-sectional study among the Finnish general population aged 25-65 years. The study population was a part of the population-based Kuopio Depression Study (KUDEP) conducted in central-eastern Finland (n=1747). Dietary data were collected using a food frequency questionnaire and dietary patterns from 22 predefined food groups, which were extracted by factor analysis. Alexithymia was assessed using the 20-item Toronto Alexithymia Scale (TAS-20) and depression using the 21-item Beck Depression Inventory (BDI-21). Altogether, 173 of the study subjects (9.9%) were alexithymic. Three dietary patterns were identified: "prudent," "Western" and "traditional." Lower scores for a healthy prudent dietary pattern and higher scores for an unhealthy Western dietary pattern were associated with an increased likelihood of belonging to the alexithymic group among subjects with elevated depressive symptoms. Among subjects without depressive symptoms, alexithymia was associated with lower scores in the prudent dietary pattern, but also with higher scores in the traditional dietary pattern. General population subjects with alexithymic features may have unhealthier dietary patterns than non-alexithymic subjects.

Factors controlling recent diatom assemblages across a steep local nutrient gradient in central-eastern Finland

The Iisalmi Route, a chain of lakes in central-eastern Finland, is more eutrophic than its surroundings. We used multivariate analyses to study the influence of selected environmental factors (water quality, basin characteristics, and subcatchment surficial geology) on the recent diatom assemblages across this steep local nutrient gradient. In addition to the spatial analysis of surface sediment diatom assemblages from 51 sampling sites (48 lakes), temporal changes in the total phosphorus (TP) concentrations of one Iisalmi Route lake (Lake Kirmanjarvi) were analyzed using weighted averaging partial least squares regression and 27 fossil diatom samples. Both TP and electrical conductivity (EC) showed statistically significant independent signals in the modern diatom data. The TP gradient was related to till grain size variation suggesting that geological factors affect the spatial TP variation directly or indirectly through differences in land use. Based on the temporal study, the direct effect of geology is most likely behind the steep nutrient gradient in the area because Lake Kirmanjarvi was found to be naturally eutrophic. EC, on the other hand, seems related to anthropogenic disturbance. Our study highlights the importance of taking the local geology into account when assessing past or present water quality or planning for lake management.

Selection of den sites by wolves in boreal forests in Finland

Very little is known about den site selection by wolves in European boreal forests. We examined the selection of den sites by wolves in central-eastern Finland, where the wolf population has markedly increased over the last 10 years. We found 26 dens belonging to 12 packs where at least one wolf had been collared as part of a long-term ecological study of the wolves in the study area. Generalized linear mixed effect models (lmer) were constructed to explain the location of den sites in terms of their distance from human-modified areas such as built-up areas, roads and agricultural land. Natural factors such as forest type, ground vegetation and the presence of a water source were also considered. Our results highlighted the significance of human-modified areas in breeding site selection by boreal wolves in boreal forests. The results also indicated that hiding cover and sight distance are highly important factors for den site selection, whereas the forest type was of negligible importance.

Haplotype associations define target regions for susceptibility loci in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by diverse and variable clinical manifestations. The etiology of SLE is still unknown, but both environmental and genetic factors are involved. Recent genome-wide scans and candidate genes studies in different ethnic groups have already suggested susceptibility loci for SLE, but most of the genetic component remains unexplained. We have previously conducted a genome-wide scan in 35 Finnish families multiply affected with SLE. With 417 microsatellite markers, we detected suggestive linkage in regions on chromosomes 6q and 14q as well as HLA on 6p. The 14q locus has also been implicated in three previous genome scans on SLE, whereas a partially overlapping region on 6q was implicated in one previous study. In an effort to obtain additional evidence for susceptibility loci on 6q and 14q and in order to refine their positions, we performed fine mapping at 1 cM density across the suggestive regions of linkage. Our results show evidence for excess sharing of a haplotype on 14q and excess transmission of a haplotype on 6q. Our results are compatible with the idea of a founder effect for susceptibility genes in SLE in central eastern Finland and suggest a path to the isolation of the putative susceptibility genes.

Susceptibility Loci for Preeclampsia on Chromosomes 2p25 and 9p13 in Finnish Families

Preeclampsia is a common, pregnancy-specific disorder characterized by reduced placental perfusion, endothelial dysfunction, elevated blood pressure, and proteinuria. The pathogenesis of this heterogeneous disorder is incompletely understood, but it has a familial component, which suggests that one or more common alleles may act as susceptibility genes. We hypothesized that, in a founder population, the genetic background of preeclampsia might also show reduced heterogeneity, and we have performed a genomewide scan in 15 multiplex families recruited predominantly in the Kainuu province in central eastern Finland. We found two loci that exceeded the threshold for significant linkage: chromosome 2p25, near marker D2S168 (nonparametric linkage [NPL] score 3.77; P=.000761) at 21.70 cM, and 9p13, near marker D9S169 (NPL score 3.74; P=.000821) at 38.90 cM. In addition, there was a locus showing suggestive linkage at chromosome 4q32 between D4S413 and D4S3046 (NPL score 3.13; P=.003238) at 163.00 cM. In the present study the susceptibility locus on chromosome 2p25 is clearly different (21.70 cM) from the locus at 2p12 found in an Icelandic study (94.05 cM) and the locus at 2q23 (144.7 cM) found in an Australian/New Zealand study. The locus at 9p13 has been shown to be a candidate region for type 2 diabetes in two recently published genomewide scans from Finland and China. The regions on chromosomes 2p25 and 9p13 may harbor susceptibility genes for preeclampsia.

Predictors of coronary heart diseases among children and adolescents in families with premature coronary heart diseases in central eastern Finland

Objective - To describe coronary heart disease (CHD) predictors in children and adolescents (aged from 7 to 16 years) in families with premature CHD. Design - A cross-sectional cohort study. Setting - Part of a family-oriented preventive intervention programme concerning CHD risk factors in central eastern Finland (FOPIC study). Subjects - 473 participants in families with premature CHD and 371 in control families. Main outcome measures - Traditional CHD predictors. Results - Offspring in families with premature CHD had significantly higher concentrations of total cholesterol (TC, 4.7 vs 4.5 mmol/l, pp<0.01) and low-density lipoprotein cholesterol (LDL-C, 2.8 vs 2.6 mmol/l, p<0.01) than the control children, and higher diastolic blood pressure (DBP, p<0.01). According to this cross-sectional screening of children in high-CHD-risk families in the Kainuu region, 75% of those with adverse cholesterol values could be found. After adjusting for confounding factors, associations between TC, LDL-C, body mass index, DBP and the offspring of families with a history of premature CHD were found. Conclusions - The results indicated strong associations between CHD predictors and offspring with a family history of premature CHD. The findings confirm the usability of familial premature CHD in screening for early prevention in primary health care.

Rb-Sr and Sm-Nd ages and isotopic geochemistry of Archaean granodioritic gneisses from Eastern Finland

Twenty granodioritic rocks and one amphibolitic enclave of the “basement” of the Suomussalmi-Kuhmo Archaean (2.65 Ga) greenstone belts (central-eastern Finland), have been chosen together with one greenstone sample for Rb-Sr and Sm-Nd geochronological and isotopic studies. The granitoïd rocks are subdivided into three groups: two generations of grey gneisses and a post-belt augen gneiss. The Rb-Sr ages of the first and second generation of grey gneisses are 2.86 ± 0.09 and 2.62 ± 0.07 Ga, respectively. These results are corroborated by Sm-Nd data. The post-belt augen gneiss gives an age of 2.51 ± 0.11 Ga. The results show that the two generations of grey gneisses, the greenstone belts and the post-greenstone augen gneiss, were developed over a period > 350 Ma. The two generations of grey gneisses show identical I Sr values (0.7023 ± 8 and 0.7024 ± 6) which contrast with that of the augen gneiss (0.7049 ± 8). The low I Sr and the near-chondritic ϵ T CHUR values indicate that the grey gneisses cannot derived from much older continental materials. Trace element studies suggest that these grey gneisses have had a multi-stage development. The augen gneiss with a moderately high I Sr is likely to be derived from a granodiorite originated by partial melting of older sialic crust. The more probable parent rock seems to be the first generation grey gneisses. The I Sr and average Rb/Sr values preclude the greenstone belt and the second generation of grey gneisses as the protolith.

Utilization of dental care in a Finnish industrial population

Ninety-three percent of the 300 employees of a paper mill in central-eastern Finland answered a questionnaire in the context of a clinical dental survey. One third had visited the dentist annually, 22% once in 2 years and the rest irregularly. Dental visit frequency of females was somewhat higher than that of males. People in younger age groups and higher income groups used more dental services, whereas those who had dentures used clearly less dental services than others. Subjective assessment of treatment need was the main reason for dental visits, more than half of the subjects had attended the dentist the last time because of self-assessed need. Thirty-eight percent went to the dentist because of toothache and only 9% for regular check-up. Although more than one third had gone to the dentist because of toothache only one third of those who had toothache during the preceding year had visited the dentist during that period. People without toothache, in fact, used more dental services than those who had had it.