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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.

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

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. Source

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

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. Source

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 Jyvaskyla
Limnology and Oceanography

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. Source

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

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. Source

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

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. Source

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