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  • Maki, Mari; Heinonsalo, Jussi; Hellen, Heidi; Back, Jaana (COPERNICUS GESELLSCHAFT MBH, 2017)
    Boreal forest floor emits biogenic volatile organic compounds (BVOCs) from the understorey vegetation and the heterogeneous soil matrix, where the interactions of soil organisms and soil chemistry are complex. Earlier studies have focused on determining the net exchange of VOCs from the forest floor. This study goes one step further, with the aim of separately determining whether the photosynthesized carbon allocation to soil affects the isoprenoid production by different soil organisms, i.e., decomposers, mycorrhizal fungi, and roots. In each treatment, photosynthesized carbon allocation through roots for decomposers and mycorrhizal fungi was controlled by either preventing root ingrowth (50 mu m mesh size) or the ingrowth of roots and fungi (1 mu m mesh) into the soil volume, which is called the trenching approach. Isoprenoid fluxes were measured using dynamic (steady-state flow-through) chambers from the different treatments. This study aimed to analyze how important the understorey vegetation is as a VOC sink. Finally, a statistical model was constructed based on prevailing temperature, seasonality, trenching treatments, understory vegetation cover, above canopy photosynthetically active radiation (PAR), soil water content, and soil temperature to estimate isoprenoid fluxes. The final model included parameters with a statistically significant effect on the isoprenoid fluxes. The results show that the boreal forest floor emits monoterpenes, sesquiterpenes, and isoprene. Monoterpenes were the most common group of emitted isoprenoids, and the average flux from the non-trenched forest floor was 23 mu gm(-2) h(-1). The results also show that different biological factors, including litterfall, carbon availability, biological activity in the soil, and physico-chemical processes, such as volatilization and absorption to the surfaces, are important at various times of the year. This study also discovered that understorey vegetation is a strong sink of monoterpenes. The statistical model, based on prevailing temperature, seasonality, vegetation effect, and the interaction of these parameters, explained 43% of the monoterpene fluxes, and 34-46% of individual alpha pinene, camphene, beta-pinene, and Delta(3)-carene fluxes.
  • Atherton, Jon; Olascoaga, Benat; Alonso, Luis; Porcar-Castell, Albert (Frontiers Media, 2017)
    Leaf Optical Properties (LOPs) convey information relating to temporally dynamic photosynthetic activity and biochemistry. LOPs are also sensitive to variability in anatomically related traits such as Specific Leaf Area (SLA), via the interplay of intra-leaf light scattering and absorption processes. Therefore, variability in such traits, which may demonstrate little plasticity over time, potentially disrupts remote sensing estimates of photosynthesis or biochemistry across space. To help to disentangle the various factors that contribute to the variability of LOPs, we defined baseline variation as variation in LOPs that occurs across space, but not time. Next we hypothesized that there were two main controls of potentially disruptive baseline spatial variability of photosynthetically-related LOPs at our boreal forest site: light environment and species. We measured photosynthetically-related LOPs in conjunction with morphological, biochemical, and photosynthetic leaf traits during summer and across selected boreal tree species and vertical gradients in light environment. We then conducted a detailed correlation analysis to disentangle the spatial factors that control baseline variability of leaf traits and, resultantly, LOPs. Baseline spatial variability of the Photochemical Reflectance Index (PRI) was strongly influenced by species and to a lesser extent light environment. Baseline variability of spectral fluorescence derived LOPs was less influenced by species; however at longer near-infrared wavelengths, light environment was an important control. In summary, remote sensing of chlorophyll fluorescence has good potential to detect variation in photosynthetic performance across space in boreal forests given reduced sensitivity to species related baseline variability in comparison to the PRI. Our results also imply that spatially coarse remote sensing observations are potentially unrepresentative of the full scope of natural variation that occurs within a boreal forest.
  • Pavicic, Mirko; Mouhu, Katriina; Wang, Feng; Bilicka, Marcelina Marta; Himanen, Kristiina Irma Helena (Frontiers Media, 2017)
    Flowering time control integrates endogenous as well as environmental signals to promote flower development. The pathways and molecular networks involved are complex and integrate many modes of signal transduction. In plants ubiquitin mediated protein degradation pathway has been proposed to be as important mode of signaling as phosphorylation and transcription. To systematically study the role of ubiquitin signaling in the molecular regulation of flowering we have taken a genomic approach to identify flower related Ubiquitin Proteasome System components. As a large and versatile gene family the RING type ubiquitin E3 ligases were chosen as targets of the genomic screen. To this end the complete list of Arabidopsis RING E3 ligases were retrieved and verified in the Arabidopsis genome v11. Their differential expression was used for their categorization into flower organs or developmental stages. Known regulators of flowering time or floral organ development were identified in these categories through literature search and representative mutants for each category were purchased for functional characterization by growth and morphological phenotyping. To this end, a workflow was developed for high throughput phenotypic screening of growth, morphology and flowering of nearly a thousand Arabidopsis plants in one experimental round.
  • Jokinen, Tuija; Kontkanen, Jenni; Lehtipalo, Katrianne; Manninen, Hanna E.; Aalto, Juho; Porcar-Castell, Albert; Garmash, Olga; Nieminen, Tuomo; Ehn, Mikael; Kangasluoma, Juha; Junninen, Heikki; Levula, Janne; Duplissy, Jonathan; Ahonen, Lauri R.; Rantala, Pekka; Heikkinen, Liine; Yan, Chao; Sipila, Mikko; Worsnop, Douglas R.; Back, Jaana; Petäjä, Tuukka; Kerminen, Veli-Matti; Kulmala, Markku (Nature Publishing Group, 2017)
    Solar eclipses provide unique possibilities to investigate atmospheric processes, such as new particle formation (NPF), important to the global aerosol load and radiative balance. The temporary absence of solar radiation gives particular insight into different oxidation and clustering processes leading to NPF. This is crucial because our mechanistic understanding on how NPF is related to photochemistry is still rather limited. During a partial solar eclipse over Finland in 2015, we found that this phenomenon had prominent effects on atmospheric on-going NPF. During the eclipse, the sources of aerosol precursor gases, such as sulphuric acid and nitrogen-containing highly oxidised organic compounds, decreased considerably, which was followed by a reduced formation of small clusters and nanoparticles and thus termination of NPF. After the eclipse, aerosol precursor molecule concentrations recovered and reinitiated NPF. Our results provide direct evidence on the key role of the photochemical production of sulphuric acid and highly oxidized organic compounds in maintaining atmospheric NPF. Our results also explain the rare occurrence of this phenomenon under dark conditions, as well as its seemingly weak connection with atmospheric ions.
  • Cibirka, N.; Cypriano, E. S.; Brimioulle, F.; Gruen, D.; Erben, T.; van Waerbeke, L.; Miller, L.; Finoguenov, A.; Kirkpatrick, C.; Henry, J. Patrick; Rykoff, E.; Rozo, E.; Dupke, R.; Kneib, J. -P.; Shan, H.; Spinelli, P. (Oxford University Press, 2017)
    We present a stacked weak-lensing analysis of 27 richness selected galaxy clusters at 0.40
  • Toli, Elisavet A.; Noreikiene, Kristina; De Faveri, Jacquelin; Merila, Juha (Wiley, 2017)
    Evidence for phenotypic plasticity in brain size and the size of different brain parts is widespread, but experimental investigations into this effect remain scarce and are usually conducted using individuals from a single population. As the costs and benefits of plasticity may differ among populations, the extent of brain plasticity may also differ from one population to another. In a common garden experiment conducted with three-spined sticklebacks (Gasterosteus aculeatus) originating from four different populations, we investigated whether environmental enrichment (aquaria provided with structural complexity) caused an increase in the brain size or size of different brain parts compared to controls (bare aquaria). We found no evidence for a positive effect of environmental enrichment on brain size or size of different brain parts in either of the sexes in any of the populations. However, in all populations, males had larger brains than females, and the degree of sexual size dimorphism (SSD) in relative brain size ranged from 5.1 to 11.6% across the populations. Evidence was also found for genetically based differences in relative brain size among populations, as well as for plasticity in the size of different brain parts, as evidenced by consistent size differences among replicate blocks that differed in their temperature.
  • Sawala, Till; Pihajoki, Pauli; Johansson, Peter H.; Frenk, Carlos S.; Navarro, Julio F.; Oman, Kyle A.; White, Simon D. M. (Oxford University Press, 2017)
    The predicted abundance and properties of the low-mass substructures embedded inside larger dark matter haloes differ sharply among alternative dark matter models. Too small to host galaxies themselves, these subhaloes may still be detected via gravitational lensing or via perturbations of the Milky Way's globular cluster streams and its stellar disc. Here, we use the APOSTLE cosmological simulations to predict the abundance and the spatial and velocity distributions of subhaloes in the range 10(6.5)-10(8.5)M(circle dot) inside haloes of mass similar to 10(12) M-circle dot in Lambda cold dark matter. Although these subhaloes are themselves devoid of baryons, we find that baryonic effects are important. Compared to corresponding dark matter only simulations, the loss of baryons from subhaloes and stronger tidal disruption due to the presence of baryons near the centre of the main halo reduce the number of subhaloes by similar to 1/4 to 1/2, independently of subhalo mass, but increasingly towards the host halo centre. We also find that subhaloes have non-Maxwellian orbital velocity distributions, with centrally rising velocity anisotropy and positive velocity bias that reduces the number of low-velocity subhaloes, particularly near the halo centre. We parametrize the predicted population of subhaloes in terms of mass, galactocentric distance and velocities. We discuss implications of our results for the prospects of detecting dark matter substructures and for possible inferences about the nature of dark matter.
  • Hellen, Heidi; Kangas, Leena; Kousa, Anu; Vestenius, Mika; Teinila, Kimmo; Karppinen, Ari; Kukkonen, Jaakko; Niemi, Jarkko V. (COPERNICUS GESELLSCHAFT MBH, 2017)
    Even though emission inventories indicate that wood combustion is a major source of polycyclic aromatic hydrocarbons (PAHs), estimating its impacts on PAH concentration in ambient air remains challenging. In this study the effect of local small-scale wood combustion on the benzo[a] pyrene (BaP) concentrations in ambient air in the Helsinki metropolitan area in Finland is evaluated, using ambient air measurements, emission estimates, and dispersion modeling. The measurements were conducted at 12 different locations during the period from 2007 to 2015. The spatial distributions of annual average BaP concentrations originating from wood combustion were predicted for four of those years: 2008, 2011, 2013, and 2014. According to both the measurements and the dispersion modeling, the European Union target value for the annual average BaP concentrations (1 ngm(-3) ) was clearly exceeded in certain suburban detached-house areas. However, in most of the other urban areas, including the center of Helsinki, the concentrations were below the target value. The measured BaP concentrations highly correlated with the measured levoglucosan concentrations in the suburban detached-house areas. In street canyons, the measured concentrations of BaP were at the same level as those in the urban background, clearly lower than those in suburban detached-house areas. The predicted annual average concentrations matched with the measured concentrations fairly well. Both the measurements and the modeling clearly indicated that wood combustion was the main local source of ambient air BaP in the Helsinki metropolitan area.
  • Venn, Stephen (CZECH ACAD SCI, INST ENTOMOLOGY, 2016)
    This review considers factors affecting the flight capacity of carabid beetles and the implications of flight for carabids. Studies from the Dutch polders in particular show that young populations of carabids consist predominantly of macropterous species and macropterous individuals of wing-dimorphic species. Also populations of wing-dimorphic carabid species at the periphery of their geographical range contain high proportions of macropterous individuals. However, studies from Baltic archipelagos show that older populations of even highly isolated island habitats contain considerable proportions of brachypterous species and individuals. This suggests that macroptery is primarily an adaptation for dispersal and that there exists a mechanism for subsequently reducing the ratio of macropterous to brachypterous species under stable conditions, due to the competitive advantage of brachyptery. Populations in isolated habitats, such as islands and mountains, have high proportions of brachypterous species. Many macropterous species do not possess functional flight muscles. Species of unstable habitats, such as tree canopies and wet habitats, are mostly macropterous. Brachypterous species tend to disappear from disturbed habitats. There is uncertainty regarding the extent to which carabid dispersal is directed and how much passive. Both Den Boer and Lindroth recognized that mostly macropterous individuals of macropterous and wing-dimorphic species disperse and found new populations, after which brachyptery tends to rapidly appear and proliferate in the newly founded population. It is most likely that the allele for brachyptery would arrive via the dispersal of gravid females which had mated with brachypterous males prior to emigration. Whilst many studies consider wing morphology traits of carabid beetles to be species-specific and permanent, a number of studies have shown that the oogenesis flight syndrome, whereby females undertake migration and subsequently lose their flight muscles by histolysis before eventually regenerating them after reproducing, has been reported for a growing number of carabid species. Wing morphology of carabid beetles clearly offers strong potential for the study of population dynamics. This field of study flourished during the 1940's to the late 1980's. Whilst a considerable amount of valuable research has been performed and published, the topic clearly holds considerable potential for future study.
  • Timmis, Kenneth; Jebok, Franziska; Rigat, Fabio; de Vos, Willem M.; Timmis, James Kenneth (Wiley, 2017)
  • Öörni, Anssi; Kuula, Markku; Pantzar, Mika (2017)
    Information systems theory tells us that the deepest going difference between utilitarian and hedonic information technology use is that different sets of motivational factors direct the two types of use. However, recent advances in social sychology and consumer behavior research suggest that there is an even more profound difference: Only utilitarian IT use depends on the self-control mechanism and the limited resources consumed bμ exercise of self-control. This causes the daily and weekly rhythms of utilitarian and hedonic use to be different. Utilitarian information technology use decreases throughout the day and the week while hedonic information technology use does not. In this paper, we test for the first time whether the daily consumption pattern of utilitarian information technology use indeed reflects the hypothesized patterns at the aggregate level. Our data suggests that it does, which means that the self-control mechanism should be integrated in the information systems models that seek to explain information technology use.
  • Roinila, Markku (Edizioni ETS, 2016)
    In §18 of Principles of Nature and Grace, Based on Reason, Leibniz says: ”Thus our happiness will never consist, and must never consist, in complete joy, in which nothing is left to desire, and which would dull our mind, but must consist in a perpetual progress to new pleasures and new perfections.” This passage is typical in Leibniz’s Nachlass. Universal perfection creates in us joy or pleasure of the mind and its source is our creator, God. When this joy is constant, we reach happiness and wisdom which is a kind of standing state of virtue, readiness to practice charity in the best of all possible worlds. However, it also indicates that our knowledge is never perfect. Perfecting our knowledge is a never-ending process which gives us joy in itself and motivates us to act in imitation of God. In this way some passions advance our knowledge and we can create ourselves a passionate habit of knowing more about the world and its perfection. In this paper I try to see this process of self-perfection from a cognitive rather than ethical point of view. While it is clear that in the final stage of wisdom we act mostly on our volitions which are founded on clear and distinct perceptions, it is less clear what cognitive status is to be attributed to our initial perceptions of perfection, our emotions and finally, the intellectual emotions which lead us to perfection and God. I will also reflect the role of the minute perceptions in our struggle for happiness. My argument is that a central cognitive role in Leibniz’s views on self-perfection is held by clear, but confused perfections which are subjective, undemonstrable impressions, shades, feelings. Therefore our ethical action is largely founded on passing, minute feelings rather than on deliberated conscious volitions, although the goal in Leibniz’s moral theory is to change this fact. My discussion is founded on several texts from Leibniz’s later philosophy, such as the discussion following from New System of the Nature and the Communication of Substances of 1695, Leibniz’s letter to Queen Sophie Charlotte of 1702 (also known as On What is Independent in Sense and Matter), New Essays on Human Understanding (1704), Theodicy (1710) and naturally Leibniz’s most important epistemological text, Meditations of Truth, Knowledge and Ideas (1684).
  • Roinila, Markku (2016)
    The Battle of the Endeavors: Dynamics of the Mind and Deliberation in New Essays, book IIAbstract for the 2016 Leibniz-Kongress, Hannover Markku Roinila In New Essays on Human Understanding, book II, chapter xxi Leibniz presents an interesting picture of the human mind as not only populated by perceptions, volitions and appetitions, but also by endeavours. The endeavours in question can be divided to entelechy and effort; Leibniz calls entelechy as primitive active forces and efforts as derivative forces. The entelechy, understood as primitive active force is to be equated with a substantial form, as Leibniz says: “When an entelechy – i.e. a primary or substantial endeavour – is accompanied by perception, it is a soul” (NE II, xxi, §1; RB, 170). What about efforts, then? One is certainly the will. In NE, II, xxi, §5 Leibniz argues that volition is the effort (conatus) to move towards what one finds good and away from what one finds bad and that this endeavor arises from the perceptions we are aware of. As an endeavour results in action unless it is prevented, from will (which is always directed to the good) and power together follows action. However, this is not so simple. Leibniz argues that there is also a second class of efforts: “There are other efforts, arising from insensible perceptions, which we are not aware of; I prefer to call these ‘appetitions’ rather than volitions” (NE II, xxi, §5; RB, 173). Although there are appetitions of which one can be aware, usually these appetitions arise from the insensible petite perceptions and are consequently affecting us subconsciously. Now, although all minute perceptions are confused perceptions, they are always related to pleasure and displeasure and also to perfection and imperfection. From this follows that there can be different efforts present in the soul at the same time: the will which is directed to apperceived good and several separate appetitions which lead to different goals, both to those which bring about perfection and pleasure of the mind (joy) and those which bring about displeasure and imperfection (sorrow). These efforts are not only in conflict with each other but may also be in conflict with entelechy. A typical case is perceiving a sensual pleasure. Our entelechy which is always directed to final causes (perfection) may be in conflict with several different appetitions which are related in different ways to the sensual pleasure in question. If our understanding is developed enough, our will resists the temptation posed by the pleasure (agreeing with entelechy), but if the temptation is too strong, the appetitions outweigh the will and the resulting action bring about imperfection and sorrow as it is related to imperfection. In this paper I will argue that deliberation in the human soul is a battle of different endeavors described above: the entelechy in the soul strives according to its law-of-the-series towards its telos (perfection) and the will accompanies it by being automatically directed to the good. This thrust towards the apparent good is aided or hindered by the appetitions which can be thought as derivative forces in the Leibnizian dynamics. Depending on whether the predominant appetitions are related to good or bad desires, the deliberation succeeds or fails in achieving the real good which is the goal of human deliberation. The successs can be facilitated beforehand by developing our understanding so that we are less easily swept away by the derivative forces (NE II, xxi, §19). A central role in this task is played by strong willing. As Martha Bolton has noted in her recent paper, an essential feature of the basic, standing endeavors is that they are continuous – although the power balance in the soul changes from moment to moment, something lingers from our previous volitions. That is why Leibniz argues that we pave way for the future deliberations by our previous voluntary actions (NE II, xxi, §23). In contrast, the appetitions are temporary, fliegende Gedanken as Leibniz says in NE II, xxi, §12. Therefore there is a constant, always changing power balance between two kinds of endeavors in the soul: primitive active force versus derivative forces. I will argue that the behavior of the forces in the soul can be understood with a vectorial model which is related to Leibniz’s early ideas of calculus of variations and which was anticipated by Arnauld and Nicole’s Port-Royal Logic. The central idea in the model is that the options are in tension towards each other and the ratio between them at each moment determines the consequent outcome. The proper relationship between the endeavors is not a simple balance, two options which exhaust each other, but a case where different efforts complement each other: “Since the final result is determined by how things weigh against one another, I should think it could happen that he most pressing disquiet did not prevail; for even If it prevailed over each of the contrary endeavours taken singly, it may be outweighed by all of them together.” Leibniz continues : “Everything which then impinges on us weighs in the balance and contributes to determining a resultant direction, almost as in mechanics” (NE II, xxi, §40; RB, 193). The different endeavors can be understood as vectors leading to different directions and the end result is a certain direction that deliberation takes. The dynamical tension between the different endeavors presents a situation where everything affects everything and the following direction, the resulting volition follows more or less automatically. In Theodicy, §325 Leibniz describes the deliberation as follows: “One might, instead of the balance, compare the soul with a force that puts forth an effort on various sides simultaneously, but which acts only at the spot where action is easiest or there is least resistance” (Huggard, 322) This kind of dynamical tension can be understood in terms of the calculus of variations where there are several possible variations available but where the dynamics of the situation results in the decision taking the “easiest” route which is more or less objectively good depending on the level of the deliberator’s understanding. In his comments to Bayle’s note L of “Rorarius” Leibniz says: “The soul, even though it has no parts, has within it, because of the multitude of representations of external things, or rather because of the representation of the universe lodged within it by the creator, a great number, or rather an infinite number, of variations (Woolhouse & Francks (ed.), ‘New System’ and Associated Texts, 101). This kind of deliberation is comparable to God’s choice of the best world with the difference that God’s understanding is infinite which again results in the fact that the choice is the best possible. Whereas in nature the easiest route taken is always optimal as nature is God’s creation, in men the goodness or badness of men’s actions is dependent on their state of wisdom, that is, how developed their understanding is. The more wise men are, the more metaphysical goodness or perfection follows from their actions.
  • Kaimio, Mirja; Saijonmaa-Koulumies, Leena; Laitinen-Vapaavuori, Outi (BioMed Central Ltd, 2017)
    Background: American Cocker Spaniels are overrepresented among breeds that require surgery as a treatment of end-stage otitis externa. However, the prevalence of otitis externa (OE) in this breed remains unknown. We reviewed the year 2010 medical records of 55 private veterinary clinics in Finland to determine the prevalence of OE in American Cocker Spaniels compared with English Cocker and English and Welsh Springer Spaniels. An American Cocker Spaniel owner questionnaire was designed to identify potential risk factors for end-stage OE. Results: From the medical records of 98,736 dogs, the prevalence of OE was highest in Welsh Springer Spaniels (149 out of 468, 31.8%, [95% confidence interval 27.6-36.0]), followed by American Cocker (89/329, 27.0%, [22.2-31.7]), English Springer (96/491, 19.6%, [16.1-23.1]) and English Cocker Spaniels (231/1467, 15.7%, [13.8-17.6]). The mean number of OE episodes in ear-diseased dogs and the number of ear surgeries were highest in American Cocker Spaniels. Owner questionnaires were received for 151 American Cocker Spaniels, 85 (56%) of which had suffered from OE. In 47% (40/85) of these dogs, OE occurred without concurrent skin lesions, 46% (33/72) displayed the first signs of OE before 1 year of age. In 24% (20/85) of the dogs, the signs of OE recurred within 1 month or continued despite treatment, 16% (14/85) required surgery (n = 11) or were euthanized (n = 5; 2 of the operated dogs and 3 others) due to severe OE. The onset of OE before the age of 1 year significantly increased the risk (OR 3.8, 95% CI 1.1-13.6) of end-stage OE. Conclusions: The prevalence of OE in American Cocker Spaniels in Finland was higher than previously reported in Cocker Spaniels, but the highest prevalence of OE was found in Welsh Springer Spaniels. Compared to the other Spaniels, OE was more often recurrent and more frequently surgically managed in American Cocker Spaniels. Based on the questionnaire, early onset (<1 year) of OE increased the risk of end-stage OE. In American Cocker Spaniels, OE requires an intensive approach from the first treatment, and prevention of recurrence should be emphasised. The causes and treatment of OE in this breed warrant further study.
  • Keinanen, Marja; Kakela, Reijo; Ritvanen, Tiina; Myllyla, Timo; Ponni, Jukka; Vuorinen, Pekka J. (BioMed Central Ltd, 2017)
    Sprat (Sprattus sprattus) and small herring (Clupea harengus) are the dominant prey fish of Atlantic salmon (Salmo salar) in the Baltic Sea. If the fatty acid (FA) proportions of sprat and herring differ, the dietary history of ascending salmon could be determined from their FA profiles. Therefore, we investigated the FA composition of several age groups of whole sprat and small herring, caught from the three main feeding areas of salmon in autumn and spring. Oleic acid (18: 1n-9) was the most prevalent FA in sprat and characteristic of this species. In herring, palmitic acid (16: 0) was the most common FA, but herring lipid was characterized by n-6 polyunsaturated FAs, and moreover, by palmitoleic acid (16: 1n-7) and vaccenic acid (18: 1n-7). Due to the higher lipid content of sprat, the concentrations of all other FAs, excluding these, were higher in sprat than in herring. The concentration of docosahexaenoic acid (DHA, 22: 6n-3) increased with an increase in the lipid content and was consequently highest in the youngest specimens, being in young sprat almost double that of young herring, and 2.6 times higher in the sprat biomass than in that of herring. As a result of a decrease in the DHA concentration with age, the ratio thiamine/DHA increased with respect to age in both species, and was lower in sprat than in herring. It is concluded that an abundance of DHA in the diet of salmon most likely increases oxidative stress because of the susceptibility of DHA to peroxidation, and thus decreases thiamine resources of fasting, prespawning salmon. Because the FA composition of sprat and herring differs, and the relative abundancies of prey fish differ between the feeding areas of salmon, the feeding area of ascending salmon can most probably be derived by comparing their FA profiles.