Novia University of Applied Sciences
Vaasa, Finland

The Novia University of Applied science is an institution of higher professional education in Finland. It offers Bachelor's and Master's degree programmes in Swedish in Vaasa, Turku, Raseborg and Jakobstad.The university was formed on August 1, 2008, by the merging of the Sydväst Polytechnic and the Swedish Polytechnic. Wikipedia.

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Xiao Y.-H.,University of Helsinki | Sara-Aho T.,Finnish Environment Institute | Hartikainen H.,University of Helsinki | Vahatalo A.V.,Novia University of Applied Sciences | Vahatalo A.V.,University of Jyväskylä
Limnology and Oceanography | Year: 2013

This study experimentally determined the contribution of ferric iron (Fe(III)) associated with humic substances (HS) to light absorption by chromophoric dissolved organic matter (CDOM). The associations between Fe(III) and HS (HS-Fe) were generated by mixing HS standards with Fe(III) in acidic conditions and adjusting pH to 8. HS-associated Fe was separated from total Fe by filtering (0.7 mm and 0.2 mm filters) and by removing the free Fe ions by cation exchange chromatography. The maximum Fe-binding capacities (at pH 8) of Suwannee River humic acid, Suwannee River fulvic acid, and Pony Lake (Antarctica) fulvic acid were 13.0, 13.5, and 7.64 mmol Fe [mg C]-1, respectively, indicating that wetland-derived HS had a higher Fe-binding capacity than planktonderived HS. HS-associated Fe increased the absorption coefficient of CDOM by up to several fold in the visible range of the spectrum and reduced the spectral slope coefficient of CDOM. The Fe-induced increase in light absorption was spectrally similar among different HS examined. The Fe-specific absorption coefficient spectrum for HS-associated Fe (alambda;,Feast;) was calculated from the Fe-induced increase in light absorption by normalizing it with the concentration of Fe in the HS pool. The alambda;,Feast; was adopted in estimation of the contribution of HSassociated Fe to light absorption by CDOM in 13 circum-neutral natural waters collected from a spring, 10 major rivers, a lake, and a coastal area. HS-associated Fe was calculated to be responsible for from 0.6% (Mississippi River) to 56.4% (Löytynlähde spring) of light absorption by CDOM at a wavelength of 410 nm. This study shows that HS-associated Fe can be an important component in light absorption by CDOM and also influence the spectral slope coefficient of CDOM. © 2013, by the Association for the Sciences of Limnology and Oceanography, Inc.

Aarnos H.,University of Helsinki | Ylostalo P.,Finnish Environment Institute | Vahatalo A.V.,University of Helsinki | Vahatalo A.V.,Novia University of Applied Sciences
Journal of Geophysical Research: Biogeosciences | Year: 2012

We studied the photochemical transformation of dissolved organic matter (DOM) to dissolved inorganic carbon (DIC), ammonium (NH4 +), and labile organic substrates supporting bacterial carbon biomass along a salinity gradient throughout the Baltic Sea during summer, autumn, and spring. The photoproduced DIC, NH4 +, and labile DOM supporting bacterial biomass were related to the number of photons absorbed during the irradiations of biologically recalcitrant DOM to determine apparent quantum yields. The apparent quantum yields for the photoproduction of DIC and NH4 + lacked seasonal variation, but behaved differently along the salinity gradient; the photoproduction of DIC decreased, while photoammonification increased with increasing salinity. The apparent quantum yield for the photoproduction of labile DOM supporting bacterial biomass was highest in summer and unaffected by salinity. The annual photoammonification rate over the entire Baltic Sea ranged from 0.038 to 0.049 Tg N, equivalent to 13%-23% of the annual atmospheric deposition of inorganic N. The annual phototransformation of dissolved organic carbon (DOC), including the direct photomineralization and indirect bacterial mineralization of photoproduced labile DOM (total of 2.71-3.94 Tg C), exceeded the annual river loading of photoreactive DOC, assuming that half of the total river DOC input to the Baltic Sea is photoreactive. As the annual photomineralization of DOC exceeded the annual terrestrial input of photoreactive DOC to the Baltic Sea, the photochemical transformation is a major sink for terrestrial DOC in such coastal systems. Copyright 2012 by the American Geophysical Union.

Jaatinen K.,Novia University of Applied Sciences | Ost M.,Novia University of Applied Sciences | Lehikoinen A.,University of Helsinki
Journal of Animal Ecology | Year: 2011

Grouping provides antipredatory benefits, and therefore aggregation tendencies increase under heightened predation risk. In socially breeding groups, however, conflicts over reproductive shares or safety tend to disintegrate groups. Group formation thereby involves a balance between the antipredatory benefits of aggregation and the destabilizing effect of reproductive conflict. We study the grouping behaviour of a facultatively social precocial sea duck with uniparental female care, the eider (Somateria mollissima Linnaeus). Females tend their young solitarily or in groups of 2-5 females. Here, we focus on the effect predation on adults has on group-formation decisions of brood-caring females. By modifying an existing bidding game over care, we model the effects of predation risk on the width of the window of selfishness, which delimits the reproductive sharing allowing cooperation within brood-rearing coalitions, and generate predictions about the relative frequencies of solitary versus cooperative parental care modes. Furthermore, we model the dilution effect as a function of female group size and predation risk. The window of selfishness widens with increasing predation risk, and the dilution of predation risk increases with both female group size and increasing predation risk, yielding the following predictions: (i) cooperative brood care becomes more prevalent and, conversely, solitary brood care less prevalent under heightened predation risk and (ii) group sizes increase concomitantly. We tested these predictions using 13 years of data on female grouping decisions and annual predation rates, while controlling for the potentially confounding effect of female body condition. Our data supported both predictions, where heightened predation risk of nesting females, but not changes in their condition, increased the relative frequency of cooperative brood care. Increased female nesting mortality also resulted in larger groups of cooperative females. The predation risk of incubating females has long-term implications for later parental care decisions. We discuss the potential consequences of predation-induced shifts in group size on per capita fitness and population-wide productivity. © 2010 The Authors. Journal compilation © 2010 British Ecological Society.

Fred M.S.,Novia University of Applied Sciences | Brommer J.E.,University of Helsinki
Animal Behaviour | Year: 2010

Apollo butterflies in Fennoscandia differ from most butterflies because they oviposit almost randomly, away from the host plant. We studied whether this apparently maladaptive behaviour could be compensated for by high accuracy of newly hatched larvae in locating host plants through either olfactory or visual cues. Olfaction capacity was quantified in a two-choice set-up (host plant versus control) in an olfactometer. Visual capacity was quantified in a small-scale open-air arena with a host plant and a dummy control placed randomly at the edge. We found no evidence that larvae oriented themselves towards the host plant in either of these experimental set-ups; instead, larvae moved in the direction of the sun, and arrested movement in the presence of a smell common to the control and treatment of the olfaction test. Because larvae do not locate their host plant at a distance, the probability of finding a host plant is likely to be critically dependent on host plant density. We tested this assumption by releasing larvae in open-air arenas with three different host plant densities. The probability of larvae reaching a host plant depended strongly on host plant density. A comparison with host plant densities observed in nature suggests that Apollo butterfly larvae require a relatively high host plant density in order to have a reasonable probability of locating a host plant before perishing. Our findings provide a clear proximate link between host plant density and larval mortality, a presumed key factor affecting population processes in the Apollo butterfly. © 2009 The Association for the Study of Animal Behaviour.

Ost M.,Novia University of Applied Sciences | Tierala T.,Elias Koulu
Behavioral Ecology | Year: 2011

The timing of vigilance and feeding in groups determines the efficiency of shared predator detection and foraging success. Behavioral monitoring of conspecifics remains controversial although synchronization is commonly observed and need not compromise predator detection. The within-group timing of vigilance shows inconsistent associations with group size, and whether nearby nongroup conspecifics affect this timing is poorly understood. Finally, it is unknown whether socially breeding parents time their activities to each other based on offspring predation risk. We studied diving common eider females (Somateria mollissima) in brood-rearing coalitions subject to gull predation of ducklings. The within-group timing of vigilance was determined by comparing observed collective vigilance, the proportion of time during which at least 1 adult group member is vigilant, with that expected assuming independent timing of activities. We determined the predictors of within-group timing of vigilance, observed collective vigilance, individual vigilance, frequency of nearby nongroup females (group outsiders), and incidence of alarm reactions. Vigilance was synchronized regardless of brood composition. Synchronization and observed collective vigilance increased with female group size, whereas synchronization decreased with increasing ratios of ducklings to tending females. Individual vigilance increased in the presence of gull alarms. Within-group timing of activities was unrelated to the presence of group outsiders, but broods with fewer ducklings (less predation dilution) were more often associated with group outsiders, the frequency of which was negatively associated with the incidence of gull alarms. Increased offspring predation risk thus reduces overlapping vigilance among adult group members and enhances attraction to nearby nongroup conspecifics. © 2011 The Author.

Diaz E.R.,Novia University of Applied Sciences | Diaz E.R.,Rhodes University | McQuaid C.D.,Novia University of Applied Sciences
Journal of Ecology | Year: 2011

It is well known that grazing contributes to spatial and temporal patterns of algal cover on rocky shores, but this effect has traditionally been studied through grazer exclusion experiments using randomly positioned treatments at particular levels on the shore. Additionally, the effects of grazing on algal composition and biomass are expected to vary across gradients of physical stress and according to grazer size classes. We examine two possible sources of spatial variability on rocky shores: (i) across-shore variability and (ii) size class of grazers. We combined this approach with an across-shore experiment, with experimental blocks running continuously from low to high shore, to examine the spatial structure of the effect strength of grazing for different size classes of grazers. The results indicate that grazing effects vary among zones, habitats and grazer size classes. Micrograzers played a weak role in structuring the algal community and composition. Both macrograzers and mesograzers were important structuring agents on the upper low shore to the mid shore, but only mesograzers were important in tidal pools. Patterns across the shore of grazing effects were dynamic and patchy, acting simultaneously at different scales. The spatial pattern of grazing effects across the shore was also variable in time and was explained by the interactions among physical and biotic factors, often at the longer (10-m scale) spatial intervals (or lags); mesograzers influenced almost the whole range of lags. We conclude, based on cross-semivariograms, that abiotic factors set variability at large scales, while the effects of biotic factors (in this case grazing) operate simultaneously at scales ranging from small to large. Synthesis.Combining zonation and across-shore experiments indicates that grazing effects do not follow a continuous gradient, but instead have a patchy distribution. This approach provides information about spatial variability that is not available using only the traditional approach, contributing to our understanding of zonation models. © 2011 The Authors. Journal of Ecology © 2011 British Ecological Society.

Ost M.,Novia University of Applied Sciences | Steele B.B.,Colby-Sawyer College
Oecologia | Year: 2010

Variation in nest concealment is puzzling given the expected strong selection for safe nest sites. Selecting a concealed nest may decrease the risk of clutch predation but hinder parents from escaping predators, providing a possible solution to this paradox. Because the relative value of current versus future reproduction may vary with breeder age or state, nest concealment may also vary as a function of these attributes. We tested four predictions of the female and clutch safety trade-off hypothesis in eiders (Somateria mollissima): (1) nest concealment is negatively related to escape possibilities, (2) our capture rate of females is higher in covered nests, (3) egg predation is higher in open nests, and (4) overall nest success is unrelated to nest habitat. We also analysed nest microhabitat preferences and nest success relative to breeder age and body condition, controlling for nest spatial centrality. As expected, nest concealment and potential escape angle were negatively related, and capture by us, indicating female predation vulnerability, increased with nest cover. Clutch size was smaller in open nests, suggesting higher partial clutch predation, while it was larger among experienced and good-condition breeders. The probability of successful hatching was unrelated to nest habitat, positively associated with breeder experience, and negatively associated with hatching date. Experienced females selected more concealed and centrally located nests without sacrificing potential escape angles. The age-specific spatial distribution of nests on islands was unrelated to nest initiation dates, indicating no apparent competition. The age-specific preference of eiders for concealed nests may reflect declining reproductive value with age or confidence in surviving despite selecting a concealed nest. The apparently positive relationship between female age and survival and fecundity in eiders refutes the former alternative. Individual improvement in choosing safe nest sites, coupled with differential survival of individuals performing well, most likely explains age-specific nest-site preference and success. © Springer-Verlag 2009.

Vehmaa A.,Novia University of Applied Sciences | Brutemark A.,Novia University of Applied Sciences | Engstrom-Ost J.,Novia University of Applied Sciences
PLoS ONE | Year: 2012

Acidification of the seas, caused by increased dissolution of CO2 into surface water, and global warming challenge the adaptation mechanisms of marine organisms. In boreal coastal environments, temperature and pH vary greatly seasonally, but sometimes also rapidly within hours due to upwelling events. We studied if copepod zooplankton living in a fluctuating environment are tolerant to climate change effects predicted for 2100, i.e., a temperature increase of 3°C and a pH decrease of 0.4. Egg production of the copepod Acartia sp. was followed over five consecutive days at four temperature and pH conditions (17°C/ambient pH; 17°C/low pH; 20°C/ambient pH; 20°C/low pH). Egg production was higher in treatments with warmer temperature but the increase was smaller when copepods were simultaneously exposed to warmer temperature and lowered pH. To reveal if maternal effects are important in terms of adaptation to a changing environment, we conducted an egg transplantation experiment, where the produced eggs were moved to a different environment and egg hatching was monitored for three days. When pH changed between the egg production and hatching conditions, it resulted in lower hatching success, but the effect was diminished over the course of the experiment possibly due to improved maternal provisioning. Warmer egg production temperature induced a positive maternal effect and increased the egg hatching rate. Warmer hatching temperature resulted also in earlier hatching. However, the temperature effects appear to be dependent on the ambient sea temperature. Our preliminary results indicate that maternal effects are an important mechanism in the face of environmental change. © 2012 Vehmaa et al.

Jaatinen K.,Novia University of Applied Sciences | Ost M.,Novia University of Applied Sciences
American Naturalist | Year: 2013

A primary benefit of grouping is diluting the individual risk of attack by predators. However, the fact that groups are formed not always by solitary adults but also by subgroups (e.g., families) has been overlooked. The subgroup-specific benefit of predator dilution depends on its relative contribution to total group size. Therefore, the willingness of a subgroup to merge with others should increase the less it contributes to total group size, but the conflicting preferences of partners may result in the preferential merger of similar- sized subgroups. Here, we evaluate how the proportional contribution of subgroups to diluting risk affects group formation. We generate predictions using a bidding game over parental care and test them using data on common eiders (Somateria mollissima), in which females with variable-sized broods may form brood-rearing coalitions. The predictions (1) that size-matched subgroups should have a higher propensity to merge, (2) that predation should increase group formation propensity, and (3) that increased bargaining power, as proxied by female body condition, should increase the time needed to establish partnerships were all supported. Partners do negotiate over their relative contributions to predator dilution, accepting or rejecting partnerships on the basis of this criterion. Our results show that consideration of the size of subgroups before merger is critical in understanding the process of group formation under the threat of predation. © 2012 by The University of Chicago.

Jaatinen K.,Novia University of Applied Sciences | Ost M.,Novia University of Applied Sciences
Animal Behaviour | Year: 2011

Lacking experience represents a constraint on solitary breeding, which may be overcome by joining groups of more experienced breeders. Also, biological market theory predicts preference for partnerships with conspecifics of the highest value. We examined the formation of cooperative brood-rearing coalitions in facultatively social eider females, Somateria mollissima. Our aim was to elucidate the hitherto neglected role of age on female group size and condition differences within groups, and to explore whether older females represent attractive coalition partners. Based on previous work, we hypothesized that older breeders are found in smaller groups, and that the attraction of older partners would override the predicted negative effect of differences in body condition on female group size. We found that older females occurred in smaller groups and that the negative relationship between condition differences and group size became less steep with increasing age of the oldest group member. We also found that the maximum body condition found in a brood-rearing coalition increased with the age of the oldest female, despite a sharp decline in the probability of the oldest individual being the one in best condition. These results demonstrate the importance of age in the formation of cooperative brood-rearing coalitions and the increase in female quality with age. The experience of older females is a valuable commodity, which attracts younger prospective coalition partners in good condition regardless of body condition differences. Our results illustrate the general principle that grouping decisions cannot be understood by viewing partner choice criteria in isolation. © 2011 The Association for the Study of Animal Behaviour.

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