Northern Finland (northern + finland)

Distribution by Scientific Domains


Selected Abstracts


The relation of tobacco smoking to tooth loss among young adults

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2004
Pekka Ylöstalo
Earlier studies have associated smoking with a higher rate of dental caries, periodontal disease and tooth loss. The aim of this cross-sectional study was to determine whether smoking is associated with tooth loss among young adults. The data consist of the 1966 birth cohort of Northern Finland, which is an unselected general population birth cohort (n = 12 058). The data were collected using a postal questionnaire in 1997,98 (n = 8690). Prevalence odds ratios and confidence intervals were estimated by applying a logistic regression model. It was found that smoking was associated with tooth loss in an exposure-dependent manner. The odds for those who smoked 16 or more pack-years were 5.30 (CI = 2.35,11.2) after adjustment for socio-economic and behavioral factors. Differences in socio-economic or health behavior are not likely to explain the findings since an exposure-response pattern was seen even when data was stratified according to sex, education and health-oriented lifestyle. A possible explanation for this association is a combination of treatment decisions and dental diseases, which are most likely associated with smoking in an exposure-dependent manner. [source]


On the climate and weather of mountain and sub-arctic lakes in Europe and their susceptibility to future climate change

FRESHWATER BIOLOGY, Issue 12 2009
R. THOMPSON
Summary 1.,The complex terrain and heterogeneous nature of the mountain environment coupled with remoteness from major centres of human activity makes mountains challenging locations for meteorological investigations. Mountainous areas tend to have more varied and more extreme weather than lowlands. 2.,The EMERGE program has the primary aim of assessing the status of remote mountain and sub-arctic lakes throughout Europe for the first time. In this study, we describe the main features of the climate, ice-cover durations and recent temperature trends of these areas. The main weather characteristics of European mountain and sub-arctic lakes are their cold temperatures and year-round precipitation. Mean annual temperatures are generally close to 0 °C, and maximum summer temperatures reasonably close to 10 °C. 3.,Maritime versus continental settings determine the main differences in annual-temperature range among lake districts (10.5 °C in Scotland to 26.7 °C in Northern Finland), and a similar factor for ice-cover duration. Radiation ranges from low (120 W m,2) in the high latitude sub-arctic and high (237 W m,2) in the southern ranges of the Pyrenees and Rila. Similarly, precipitation is high in the main Alpine chain (250 cm year,1 in the Central Southern Alps) and low in the continental sub-arctic (65 cm year,1 in Northern Finland). 4.,The main temporal patterns in air temperature follow those of the adjacent lowlands. All the lake districts warmed during the last century. Spring temperature trends were highest in Finland; summer trends were weak everywhere; autumn trends were strongest in the west, in the Pyrenees and western Alps; while winter trends varied markedly, being high in the Pyrenees and Alps, low in Scotland and Norway and negative in Finland. 5.,Two new, limnological case studies on Lake Redon, in the Pyrenees, highlight the sensitivity of remote lakes to projected changes in the global climate. These two case studies involve close linkages between extreme chemical-precipitation events and synoptic wind-patterns, and between thermocline behaviour and features of the large-scale circulation. 6.,Individual lakes can be ultra-responsive to climate change. Even modest changes in future air temperatures will lead to major changes in lake temperatures and ice-cover duration and hence probably affect their ecological status. [source]


Winter Art Education Project

INTERNATIONAL JOURNAL OF ART & DESIGN EDUCATION, Issue 3 2007
Timo Jokela
The purpose of this article is to describe how the Department of Art Education at the University of Lapland in Finland has developed winter art as a method of environmental and community-based art education. I will focus on the Snow Show Winter Art Education Project, a training project funded by the European Union and the State Provincial Office of Lapland. The general aim of the project was to increase the know-how of winter art in Northern Finland. This goal was put into practice through workshops on snow construction, documentation of winter art, winter-oriented media production, and snow and ice sculpting; through continuing education seminars, workshops, and school projects for teachers; and through public lectures and seminars on winter and winter art. In this article, I describe the challenges that winter offers to community and environment-based art education in the North. Further, I introduce the methods of implementation and the outcomes of winter art exercises carried out by several schools in Lapland in cooperation with and inspired by the Snow Show Winter Art Education Project. [source]


Parkinson's disease and suicide: a profile of suicide victims with Parkinson's disease in a population-based study during the years 1988,2002 in Northern Finland

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 9 2009
Arja Mainio
Abstract Objective We studied the prevalence of hospital-treated Parkinson's disease (PD) among suicide victims and the profile of these persons, taking into account suicide attempts, timing of depression and comorbid somatic diseases. Methods The database of this study consisted of suicide victims aged 50 years of age or older (n,=,555) during a fourteen-year period in the province of Oulu in Northern Finland. Results Hospital-treated Parkinson's disease occurred in 1.6% of the subjects, indicating a rather low prevalence of suicide in this group of patients. The persons with PD had attempted suicide earlier in 44% of the cases, while the corresponding percentage for other victims in older age was 9.9% (p,=,0.009 Fischer exact test). Conclusions Based on the case characteristics of our study the profile of PD person who completed suicide was as follows: male subject with recently diagnosed disease, living in rural area, having multiple physical illnesses, and having attempted suicide earlier. Psychiatric consultation is thus highly recommended for the PD patients with this disease profile. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Suicide after hospitalization in the elderly: a population based study of suicides in Northern Finland between 1988,2003

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 2 2008
Kaisa Karvonen
Abstract Objective Elderly people commit suicide more often than people under the age of 65. An elevated risk is also attached to depression and other axis I psychiatric disorders. However, little is known about the preferred suicide method, effect of primary psychiatric diagnosis, and length of time between discharge from psychiatric hospitalization and suicide. The lack of information is most apparent in the oldest old (individuals over 75 years). Methods On the basis of forensic examinations, data on suicide rates were separately examined for the 50,64, 65,74 and over 75 year-olds (Total n,=,564) with regard to suicide method, history of psychiatric hospitalization and primary diagnoses gathered from the Finnish Hospital Discharge Register. Study population consisted of all suicides committed between 1988 and 2003 in the province of Oulu in Northern Finland. Results Of the oldest old, females had more frequent hospitalizations than males in connection with psychiatric disorders (61% vs 23%), of which depression was the most common (39% vs 14%). In this age group, 42% committed suicide within 3 months after being discharged from hospital and 83% used a violent method. Both elderly males and females were less often under the influence of alcohol, but used more often violent methods than middle-aged persons. Conclusions Suicide rates within the first 3 months following discharge from hospital in the 65,74 and the over 75 year olds were substantial and should influence post-hospitalization treatment strategies. To reduce the risk of suicides in elderly patients discharged from hospital, close post-hospitalization supervision combined with proper psychoactive medication and psychotherapy, are possible interventions. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Agreement between self-reported and pharmacy data on medication use in the Northern Finland 1966 Birth Cohort

INTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2010
Marianne Haapea
Abstract Objective: To compare self-reported (SR) medication use and pharmacy data for major psychoactive medications and three classes of medications used for different indications, and to determine the socio-economic factors associated with the congruence. Methods: Postal questionnaire data collected in 1997 were compared with the register of the Social Insurance Institution of Finland on the reimbursed prescriptions purchased during 1997. Altogether 7625 subjects were included in this study. Drugs were categorized according to the Anatomical Therapeutic Chemical (ATC) system. Results: Kappa values were 0.77, 0.68, 0.84, 0.92 and 0.55 for antipsychotics, antidepressants, antiepileptics, antidiabetics and beta-blocking agents, respectively. Prevalence-adjusted and bias-adjusted kappa values were almost perfect (0.98,1.00). Reliability of antipsychotics use was better for married subjects than for those who were not married; and of antidepressants use for highly educated and married subjects than for those who were less educated and were not married. Altogether 414 (5.4%) responders and 285 (7.1%) non-responders had used at least one of the selected medications. Conclusion: Agreement between the SR and pharmacy data was moderate for psychoactive medication use. Even though data collected by postal questionnaire may underestimate the prevalence of medication use due to non-participation it can be assumed accurate enough for study purposes. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Self-reported gingivitis and tooth loss poorly predict C-reactive protein levels: a study among Finnish young adults

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2008
Pekka V. Ylöstalo
Abstract Objectives: Our aim in this cross-sectional study was to investigate whether self-reported gingivitis and tooth loss were associated with elevated levels of C-reactive protein (CRP) using the same study population where these dental conditions have earlier been associated with prevalent angina pectoris. Material and Methods: The study population consisted of those Northern Finland birth cohort 1966 members who lived in Northern Finland or in the Helsinki region (n=8463) at the time of the survey (1996,1997). The participation rate in a health examination was 71% (n=6033). Gingivitis and tooth loss were determined on the basis of self-reported questions. Prevalence proportion ratios (PPR) and 95% confidence intervals (CI) were estimated using multivariate regression models. Results: The results showed that self-reported gingivitis and tooth loss were weakly associated with elevated levels of CRP (>3 mg/l): adjusted PPR 1.1, CI 1.0,1.3 and PPR 1.1, CI 0.7,1.7, respectively. The proportion of variation in CRP explained by self-reported gingivitis and tooth loss was small, being <1%. Conclusion: The results suggest that self-reported gingivitis and tooth loss have a miniscule effect on CRP levels among a general population of young adults. [source]


Lip cancer in Northern Finland: changing incidence and clinical characteristics

JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 7 2000
Olli-Pekka Alho
Abstract: A population-based survey was conducted in 35 municipalities in Northern Finland to assess the incidence of lip cancer as well as the patient and tumour characteristics in cases diagnosed between 1983 and 1997. A total of 96 new patients emerged. The age-standardised incidence (per 100,000 years) of lip cancer in men decreased from 4.8 in 1983,1987 to 1.4 in 1993,1997. The incidences in women were 0.30 to 0.36, respectively. The median age of the patients increased from 66 to 73 years through the years. Overall, 90% of the patients had at least one of the known risk factors, namely rural domicile, outdoor occupation or smoking. The median duration of symptoms also remained the same, as did the median size and location of the tumour at diagnosis. In contrast, spread to regional lymph nodes became rare during the period. [source]


Vacuum-assisted delivery is associated with late-onset asthma

ALLERGY, Issue 10 2009
L. Keski-Nisula
Background:, Perinatal factors during delivery might modulate fetal immunological development and thereby be associated with the development of allergic diseases and asthma later. Methods:, Perinatal data was recorded during pregnancy and at the time of delivery in regard to 5823 children who were born in Northern Finland in 1985,1986. Data from self-administered questionnaires were available at the ages of 7 and 15,16 years and skin prick tests for four main allergens were carried out at the age of 15,16 years. Only singletons delivered by the vaginal route were analyzed. Results:, There was a higher prevalence of doctor-diagnosed asthma at any time of life among children who were delivered by vacuum extraction (RR 1.80, 95% CI 1.27,2.56; P < 0.001) in comparison with spontaneously delivered children. In particular, this risk was increased as regards late-onset asthma (RR 2.41, 95% CI 1.52,3.81; P < 0.001). Perinatal effects had less impact on the development of other asthma, atopy or hay fever. Conclusions:, The delivery by vacuum extraction had significant impact on the development of late-onset asthma compared with spontaneously delivered children. [source]


Cost-Efficiency of Decaying Wood as a Surrogate for Overall Species Richness in Boreal Forests

CONSERVATION BIOLOGY, Issue 1 2006
ARTTI JUUTINEN
biodiversidad; gestión de bosques; indicadores de riqueza de especies; seleccion de sitios Abstract:,Decaying wood is one of the most important elements for species richness in boreal forests. We tested how well reserve selection based on the amount and quality of decaying wood results in a representation of four ecologically different taxa (beetles, birds, wood-inhabiting fungi, and vascular plants). We also compared the cost-efficiency of the use of dead-wood indicators with comprehensive species inventory. Our database included 32 seminatural old-forest stands located in northern Finland. Decaying wood was a relatively good indicator of saproxylic species but not overall species richness. Even though dead wood did not reflect accurately overall species richness, our results indicated that the use of decaying wood as an indicator in site selection was more cost-efficient than using information from large-scale species inventories. Thus, decaying wood is a valuable surrogate for species richness, but other cost-efficient indicators that reflect the requirements of those species which are not dependent on decaying wood should be identified. Resumen:,La madera en descomposición es uno de los elementos importantes para la riqueza de especies en bosques boreales. Probamos como resulta la selección de reservas con base en la cantidad y calidad de madera en descomposición en la representación de cuatro taxa ecológicamente distintos (escarabajos, aves, hongos habitantes en la madera y plantas vasculares). También comparamos la rentabilidad del uso de indicadores de madera muerta con inventarios integrales de especies. Nuestra base de datos incluyó 32 sitios de bosque maduro seminatural localizados en el norte de Finlandia. La madera en descomposición fue un indicador relativamente bueno de especies saproxílicas pero no de la riqueza total. Aunque la madera en descomposición no reflejó la riqueza total con precisión, nuestros resultados indicaron que el uso de madera en descomposición como un indicador en la selección de sitios fue más rentable que el uso de información de inventarios de especies de gran escala. Por lo tanto, la madera en descomposición es un sustituto valioso de la riqueza de especies, pero se deben identificar otros indicadores rentables que reflejen los requerimientos de aquellas especies que no dependen de la madera en descomposición. [source]


Food composition, habitat use and growth of stocked and native Arctic charr, Salvelinus alpinus, in Lake Muddusjärvi, Finland

FISHERIES MANAGEMENT & ECOLOGY, Issue 4 2002
K. KAHILAINEN
Habitat use, growth and food composition of native and stocked Arctic charr, Salvelinus alpinus (L.), were studied in the subarctic Lake Muddusjärvi, northern Finland, to investigate reasons for poor stocking success. Samples were collected with pelagic and epibenthic gill nets. Stocked and native charr occurred in similar epibethic habitats, whereas pelagic habitat was avoided. Native charr grew fast after shifting to piscivory. Growth rate of stocked charr was slow because only a small proportion of stocked fish became piscivorous during the first year after stocking. During the first lake year, stocked charr divided into slow-growing planktivores and fast-growing piscivores. Piscivorous stocked and native charr consumed only whitefish, Coregonus lavaretus (L.), as their prey. Small-sized (<10 cm) whitefish were preferred when shifting to piscivory. [source]


Assembly rules and community models for unicellular organisms: patterns in diatoms of boreal streams

FRESHWATER BIOLOGY, Issue 4 2005
JANI HEINO
Summary 1. Many studies have addressed either community models (e.g. Clementsian versus Gleasonian gradients) or assembly rules (e.g. nestedness, checkerboards) for higher plant and animal communities, but very few studies have examined different non-random distribution patterns simultaneously with the same data set. Even fewer studies have addressed generalities in the distribution patterns of unicellular organisms, such as diatoms. 2. We studied non-randomness in the spatial distribution and community composition of stream diatoms. Our data consisted of diatom surveys from 47 boreal headwater streams and small rivers in northern Finland. Our analytical approaches included ordinations, cluster analysis, null model analyses, and associated randomisation tests. 3. Stream diatom communities did not follow discrete Clementsian community types, where multiple species occur exclusively in a single community type. Rather, diatom species showed rather individualistic responses, leading to continuous Gleasonian variability in community composition. 4. Although continuous variability was the dominating pattern in the data, diatoms also showed significant nestedness and less overlap in species distribution than expected by chance. However, these patterns were probably only secondary signals from species' individualistic responses to the environment. 5. Although unicellular organisms, such as diatoms, differ from multicellular organisms in several biological characteristics, they nevertheless appear to show largely similar non-random distribution patterns previously found for higher plants and metazoans. [source]


Modelling patterned ground distribution in Finnish Lapland: an integration of topographical, ground and remote sensing information

GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 1 2006
Jan Hjort
Abstract New data technologies and modelling methods have gained more attention in the field of periglacial geomorphology during the last decade. In this paper we present a new modelling approach that integrates topographical, ground and remote sensing information in predictive geomorphological mapping using generalized additive modelling (GAM). First, we explored the roles of different environmental variable groups in determining the occurrence of non-sorted and sorted patterned ground in a fell region of 100 km2 at the resolution of 1 ha in northern Finland. Second, we compared the predictive accuracy of ground-topography- and remote-sensing-based models. The results indicate that non-sorted patterned ground is more common at lower altitudes where the ground moisture and vegetation abundance is relatively high, whereas sorted patterned ground is dominant at higher altitudes with relatively high slope angle and sparse vegetation cover. All modelling results were from good to excellent in model evaluation data using the area under the curve (AUC) values, derived from receiver operating characteristic (ROC) plots. Generally, models built with remotely sensed data were better than ground-topography-based models and combination of all environmental variables improved the predictive ability of the models. This paper confirms the potential utility of remote sensing information for modelling patterned ground distribution in subarctic landscapes. [source]


Carbon dioxide balance of a fen ecosystem in northern Finland under elevated UV-B radiation

GLOBAL CHANGE BIOLOGY, Issue 4 2009
JAANA K. HAAPALA
Abstract The effect of elevated UV-B radiation on CO2 exchange of a natural flark fen was studied in open-field conditions during 2003,2005. The experimental site was located in Sodankylä in northern Finland (67°22,N, 26°38,E, 179 m a.s.l.). Altogether 30 study plots, each 120 cm × 120 cm in size, were randomly distributed between three treatments (n=10): ambient control, UV-A control and UV-B treatment. The UV-B-treated plots were exposed to elevated UV-B radiation level for three growing seasons. The instantaneous net ecosystem CO2 exchange (NEE) and dark respiration (RTOT) were measured during the growing season using a closed chamber method. The wintertime CO2 emissions were estimated using a gradient technique by analyzing the CO2 concentration in the snow pack. In addition to the instantaneous CO2 exchange, the seasonal CO2 balances during the growing seasons were modeled using environmental data measured at the site. In general, the instantaneous NEE at light saturation was slightly higher in the UV-B treatment compared with the ambient control, but the gross photosynthesis was unaffected by the exposure. The RTOT was significantly lower under elevated UV-B in the third study year. The modeled seasonal (June,September) CO2 balance varied between the years depending on the ground water level and temperature conditions. During the driest year, the seasonal CO2 balance was negative (net release of CO2) in the ambient control and the UV-B treatment was CO2 neutral. During the third year, the seasonal CO2 uptake was 43±36 g CO2 -C m,2 in the ambient control and 79±45 g CO2 -C m,2 in the UV-B treatment. The results suggest that the long-term exposure to high UV-B radiation levels may slightly increase the CO2 accumulation to fens resulting from a decrease in microbial activity in peat. However, it is unlikely that the predicted development of the level of UV-B radiation would significantly affect the CO2 balance of fen ecosystems in future. [source]


Estimating winter evaporation in boreal forests with operational snow course data

HYDROLOGICAL PROCESSES, Issue 8 2003
Angela Lundberg
Abstract Snow course measurements from 11 sites located in eastern and northern Finland were used to estimate the total interception evaporation of a winter season for different forest categories. We categorized the sites based on forest density and tree species. Results showed that interception loss from gross precipitation increased with forest density and approached 30% for a forest with the highest density class. Interception loss for the most common forest density class was 11%. Interception losses were slightly larger in spruce forests than in pine, deciduous, or mixed forests. We provide suggestions as to how to design snow surveys to estimate wintertime interception evaporation better. Rough terrain and transition zones between forest and open areas should be avoided. Since evaporation fraction was strongly dependent on tree crown characteristics, snow course data should include direct estimates of canopy closure. Qualitative observations made by different observers should be given a reference frame to ensure comparability of records from different sites. Copyright © 2003 John Wiley & Sons, Ltd. [source]


The influence of natural conditions on the spatial variation of climate in Lapland, northern Finland

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2003
Andrea Vajda
Abstract At high latitudes in Lapland, near the climatological timberline, forestry and other environmental research require detailed information about the spatial variation of climate. In this study, the influence of local geographical factors on the climate in northern Finland (Lapland), as well as the applicability of the kriging interpolation method in the case of detailed spatial resolution, were examined. The spatial analysis of mean, maximum, minimum temperatures, length of the frost-free season, degree-days and daily range was made using a 1 km × 1 km resolution. The time period used was 1971,2000. We studied whether taking account of external forcing, such as lake coverage and altitude, would improve the accuracy of spatial interpolation of climatological parameters. The geographical factors of coordinates, elevation, lakes and sea influence on the regional features of the climate were examined. According to the results of this study, only geographical position and local relief have a significant influence on regional climate in Lapland. The effect of lakes and sea seems to be secondary. Copyright © 2003 Royal Meteorological Society [source]


Are urban bird communities influenced by the bird diversity of adjacent landscapes?

JOURNAL OF APPLIED ECOLOGY, Issue 5 2001
Philippe Clergeau
Summary 1The species diversity of adjacent landscapes influences the conservation or restoration of several animal groups in urban areas, but the effect on birds is unclear. To address this question, we compared bird species richness (BSR) and community composition between periurban (area surrounding the town) and urban (suburban and centre areas) landscapes across three spatial scales. 2At a large biogeographical scale (temperate and boreal climatic zone), relationships between the BSR of urban areas and their surrounding landscapes were examined in a meta-analysis of 18 published studies. In general, BSR was negatively correlated with latitude and urbanization. The BSR of suburban and centre landscapes correlated positively with the BSR of periurban landscapes. However, latitudinal effects were also involved, as BSR in urban and periurban landscapes declined as town latitude increased. Similarity indices were low (50%) between periurban and centre bird communities. 3At a regional scale, we assessed winter bird data from several towns within three regions of temperate and boreal countries (western France, northern Finland and eastern Canada). The type of periurban landscape, number of inhabitants and town diameter did not affect BSR. BSR was similar between the cities of a given biogeographical area. Bird communities were more similar between similar habitat types of different cities than between different habitats of the same city. 4At a local scale, we tested the influence of proximity to the periurban landscape on BSR in parks of western French towns of different size. Neither BSR nor community similarity changed in relation to the distance of the park from the periurban landscape. 5Guild composition according to diet and feeding habitat did not vary between urban and periurban locations at regional or local scales. 6We conclude that, at regional and local scales, urban bird communities are independent of the bird diversity of adjacent landscapes, and that local features are more important than surrounding landscapes in determining BSR. Whatever the biodiversity quality of the periurban landscape, site-specific actions such as shrub and tree planting, water restoration and increasing vegetation diversity can change bird diversity in towns and improve the quality of human,wildlife contacts. [source]


Habitat preference by grayling (Thymallus thymallus) in an artificially modified, hydropeaking riverbed: a contribution to understand the effectiveness of habitat enhancement measures

JOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2003
T. Vehanen
Summary This paper describes a case study to rehabilitate habitat for adult European grayling (Thymallus thymallus L.) in a large river reservoir in northern Finland. A channelled river reach was restored by building small islands and reefs as well as cobble and boulder structures for grayling. The total area of the restored stretch was 1.0 ha. The physical habitat was mapped using an echosounder, Doppler device, tachometer and scuba diving, and modelled with a 2D hydraulic model. The mean water velocity in the modelled stream section was 0.28 m s,1 during 110 m3 s,1 flow and 0.43 m s,1 during 300 m3 s,1 flow. Twelve adult grayling, tagged with transmitters, were released into the area and tracked for a maximum period of 30 days. The grayling largely stayed in the restored area and tended to avoid the unchanged channel of the river. The range of daily movement was from stationary to 2700 m per day. The adult grayling preferred water velocities between 0.20 and 0.45 m s,1, water depths between 0.20 and 1.55 m and coarse substrate. The study provides a small part of the information needed in habitat restoration for grayling. [source]


Species richness,standing crop relationship in stream bryophyte communities: patterns across multiple scales

JOURNAL OF ECOLOGY, Issue 1 2001
Risto Virtanen
Summary 1,We tested for a unimodal (,hump-backed') relationship between species richness and standing crop at various spatial scales in stream bryophyte communities. Bryophyte species and their biomasses were determined from 20 to 25 quadrats in eight river and six stream sites in northern Finland. 2,Regression analyses revealed a quadratic relationship between richness and biomass in only two of the river sites and a positive correlation in one other. A quadratic relationship was detected in three stream sites and richness increased linearly with biomass in another. 3,We also tested for the hump-shaped pattern across individual stream boulders, representing an elevational gradient from continuously submerged to permanently dry conditions, with an intermediate zone with fluctuating water level. 4,Species richness-standing crop relationship conformed to the hump-backed model only when samples from all three microhabitats were included in the analysis. A significant positive correlation occurred in the exposed low biomass end of the gradient which is characterized by semi-aquatic species, whereas the relationship tended to be negative in permanently submerged areas with high biomass of large canopy-forming species. Quadrats close to the water level had intermediate standing crop and highest species richness. 5,Species dominant at either end of the gradient appeared unable to monopolize space in the intermediate zone where disturbances (e.g. scouring by ice) detach mosses from the substratum, creating vacant gaps for colonization. The unimodal relationship between richness and biomass is likely to occur only in streams that contain large boulders protruding above the water line, thus providing scope for community diversification along very short vertical distances. [source]


Understorey plant and soil responses to disturbance and increased nitrogen in boreal forests

JOURNAL OF VEGETATION SCIENCE, Issue 2 2009
O.H. Manninen
Abstract Question: How do N fertilization and disturbance affect the understorey vegetation, microbial properties and soil nutrient concentration in boreal forests? Location: Kuusamo (66°22,N; 29°18,E) and Oulu (65°02,N; 25°47,E) in northern Finland. Methods: We conducted a fully factorial experiment with three factors: site (two levels), N fertilization (four levels) and disturbance (two levels). We measured treatment effects on understorey biomass, vegetation structure, and plant, soil and microbial N and C concentrations. Results: The understorey biomass was not affected by fertilization either in the control or in the disturbance treatment. Fertilization reduced the biomass of deciduous Vaccinium myrtillus. Disturbance had a negative effect on the biomass of V. myrtillus and evergreen Vaccinium vitis-idaea and decreased the relative proportion of evergreen species. Fertilization and disturbance increased the biomass of grass Deschampsia flexuosa and the relative proportion of graminoids. The amount of NH4+ increased in soil after fertilization, and microbial C decreased after disturbance. Conclusions: Our results suggest that the growth of slow-growing Vaccinium species and soil microbes in boreal forests are not limited by N availability. However, significant changes in the proportion of dwarf shrubs to graminoids and a decrease in the biomass of V. myrtillus demonstrate the susceptibility of understorey vegetation to N enrichment. N enrichment and disturbance seem to have similar effects on understorey vegetation. Consequently, increasing N does not affect the rate or the direction of recovery after disturbance. Moreover, our study demonstrates the importance of understorey vegetation as a C source for soil microbes in boreal forests. [source]


Generalized linear modelling in periglacial studies: terrain parameters and patterned ground

PERMAFROST AND PERIGLACIAL PROCESSES, Issue 4 2004
Miska Luoto
Abstract Generalized linear models (GLM) are mathematical extensions of linear models. GLM models are more flexible and better suited for analysing relationships of spatial data, which can often be poorly represented by classical Gaussian distributions such as least-square-regression techniques. This paper demonstrates GLM model-building procedures step-by-step for the distribution and abundance of active patterned ground in northern Finland. The exercise is based on data from an area of 200,km2 (800 modelling squares of 0.25,km2). Both the distribution and abundance models clearly indicate an increasing activity of patterned ground with (1) increasing soil moisture and (2) proportion of concave topography. Activity decreases with increasing altitude. We conclude that GLM techniques combined with a geographic information system can play an important role in analysing and modelling periglacial data sets. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Thermokarst ponds as indicators of the former distribution of palsas in Finnish Lapland

PERMAFROST AND PERIGLACIAL PROCESSES, Issue 1 2003
Miska Luoto
Abstract Thermokarst ponds resulting from thawing of palsas were mapped in a 95 km-long transect area in northern Finland. The spatial distribution of thermokarst was related to palsa distribution and to geographical variables using GIS techniques and multivariate spatial modelling. In our 3370 km2 study area, the former distribution of palsas was about three times larger than the present one. This indicates that the formation and thawing of permafrost are not in balance; palsas are collapsing and melting more often than palsas are forming. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Prevalence and associated factors of restless legs in a 57-year-old urban population in northern Finland

ACTA NEUROLOGICA SCANDINAVICA, Issue 1 2010
A. K. Juuti
Juuti AK, Läärä E, Rajala U, Laakso M, Härkönen P, Keinänen-Kiukaanniemi S, Hiltunen L. Prevalence and associated factors of restless legs in a 57-year-old urban population in northern Finland. Acta Neurol Scand: 2010: 122: 63,69. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objective,,, We examined the prevalence and associated factors of restless legs syndrome (RLS) in a 57-year-old unselected urban population in northern Finland. Methods,,, A health survey was conducted in 2002 that targeted persons born in 1945 and residing in the city of Oulu on 31 December, 2001. Their history of RLS, coronary heart disease (CHD), daytime sleepiness, depressive symptoms and snoring was assessed by means of questionnaires. Results,,, Altogether 995 of 1332 eligible subjects (74%) participated (556 women, 439 men). The overall prevalence of RLS , 1 per week was 20% in women and 15% in men. In the fitted multiple logistic regression model, RLS was found to be associated with female gender (OR 1.64, 95% CI 0.98,2.72), CHD (OR 2.92, 95% CI 1.18,7.23), daytime sleepiness (OR 2.12, 95% CI 1.32,3.41), moderately elevated (31,45) or high (46,65) Zung sum scores (OR 1.95, 95% CI 1.09,3.48 and OR 3.67, 95% CI 1.71,7.90, respectively), antidepressant medication (OR 2.10, 95% CI 1.06,4.19) and arthropathy (OR 1.69, 95% CI 1.04,2.72). Insufficient evidence was found of an association between RLS and type 2 diabetes or impaired glucose regulation. Conclusions,,, Restless legs syndrome is fairly common in subjects aged 57 years. A particularly strong positive association was observed between RLS and depressive symptoms and CHD. [source]


A mobile eye unit for screening of diabetic retinopathy and follow-up of glaucoma in remote locations in northern Finland

ACTA OPHTHALMOLOGICA, Issue 8 2009
Nina Hautala
No abstract is available for this article. [source]