Effect of species composition on economic return in amixed stand of Norway spruce and Scots Pine

Summary

Dispersal and metacommunity dynamics in a soft-sediment benthic system : how well is the seafloor connected?

Connectivity depends on rates of dispersal between communities. For marine soft-sediment communities continued small-scale dispersal as post-larvae and as adults can be equally important in maintaining community composition, as initial recruitment of substrate by pelagic larvae. In this thesis post-larval dispersal strategies of benthic invertebrates, as well as mechanisms by which communities are connected were investigated. Such knowledge on dispersal is scarce, due to the difficulties in actually measuring dispersal directly in nature, and dispersal has not previously been quantified in the Baltic Sea. Different trap-types were used underwater to capture dispersing invertebrates at different sites, while in parallel measuring waves and currents. Local community composition was found to change predictably under varying rates of dispersal and physical connectivity (waves and currents). This response was, however, dependent on dispersal-related traits of taxa. Actively dispersing taxa will be relatively better at maintaining their position, as they are not as dependent on hydrodynamic conditions for dispersal and will be less prone to be passively transported by currents. Taxa also dispersed in relative proportions that were distinctly different from resident community composition and a significant proportion (40 %) of taxa were found to lack a planktonic larval life-stage. Community assembly was re-started in a large-scale manipulative field experiment over one year across several sites, which revealed how patterns of community composition (α-, β- and λ-diversity) change depending on rates of dispersal. Results also demonstrated that in response to small-scale disturbance, initial recruitment was by nearby-dominant species after which other species arrived from successively further away. At later assembly time, the number of coexisting species increased beyond what was expected purely by local niche requirements (species sorting), transferring regional differences in community composition (β-diversity) to the local scale (α-diversity, mass effect). Findings of this thesis complement more theoretical studies in metacommunity ecology by demonstrating that understanding how and when individuals disperse relative to underlying environmental heterogeneity is key to interpreting how patterns of diversity change across different spatial scales. Such information from nature is critical when predicting responses to, for example, different types of disturbances or management actions in conservation.

Disturbance and ecosystem functioning : the role of changes in benthic biological traits

Rapid changes in biodiversity are occurring globally, as a consequence of anthropogenic disturbance. This has raised concerns, since biodiversity is known to significantly contribute to ecosystem functions and services. Marine benthic communities participate in numerous functions provided by soft-sedimentary ecosystems. Eutrophication-induced oxygen deficiency is a growing threat against infaunal communities, both in open sea areas and in coastal zones. There is thus a need to understand how such disturbance affects benthic communities, and what is lost in terms of ecosystem functioning if benthic communities are harmed. In this thesis, the status of benthic biodiversity was assessed for the open Baltic Sea, a system severely affected by broad-scale hypoxia. Long-term monitoring data made it possible to establish quantitative biodiversity baselines against which change could be compared. The findings show that benthic biodiversity is currently severely impaired in large areas of the open Baltic Sea, from the Bornholm Basin to the Gulf of Finland. The observed reduction in biodiversity indicates that benthic communities are structurally and functionally impoverished in several of the sub-basins due to the hypoxic stress. A more detailed examination of disturbance impacts (through field studies and -experiments) on benthic communities in coastal areas showed that changes in benthic community structure and function took place well before species were lost from the system. The degradation of benthic community structure and function was directed by the type of disturbance, and its specific temporal and spatial characteristics. The observed shifts in benthic trait composition were primarily the result of reductions in species’ abundances, or of changes in demographic characteristics, such as the loss of large, adult bivalves. Reduction in community functions was expressed as declines in the benthic bioturbation potential and in secondary biomass production. The benthic communities and their degradation accounted for a substantial proportion of the changes observed in ecosystem multifunctionality. Individual ecosystem functions (i.e. measures of sediment ecosystem metabolism, elemental cycling, biomass production, organic matter transformation and physical structuring) were observed to differ in their response to increasing hypoxic disturbance. Interestingly, the results suggested that an impairment of ecosystem functioning could be detected at an earlier stage if multiple functions were considered. Importantly, the findings indicate that even small-scale hypoxic disturbance can reduce the buffering capacity of sedimentary ecosystem, and increase the susceptibility of the system towards further stress. Although the results of the individual papers are context-dependent, their combined outcome implies that healthy benthic communities are important for sustaining overall ecosystem functioning as well as ecosystem resilience in the Baltic Sea.

The collective dimension of freedom of religion or belief in international law : the application of findings to the case of Turkey

Pertinent domestic and international developments involving issues related to tensions affecting religious or belief communities have been increasingly occupying the international law agenda. Those who generate and, thus, shape international law jurisprudence are in the process of seeking some of the answers to these questions. Thus the need for reconceptualization of the right to freedom of religion or belief continues as demands to the right to freedom of religion or belief challenge the boundaries of religious freedom in national and international law. This thesis aims to contribute to the process of “re-conceptualization” by exploring the notion of the collective dimension of freedom of religion or belief with a view to advance the protection of the right to freedom of religion or belief. The case of Turkey provides a useful test case where both the domestic legislation can be assessed against international standards, while at the same time lessons can be drawn for the improvement of the standard of international review of the protection of the collective dimension of freedom of religion or belief. The right to freedom of religion or belief, as enshrined in international human rights documents, is unique in its formulation in that it provides protection for the enjoyment of the rights “in community with others”.1 It cannot be realized in isolation; it crosses categories of human rights with aspects that are individual, aspects that can be effectively realized only in an organized community of individuals and aspects that belong to the field of economic, social and cultural rights such as those related to religious or moral education. This study centers on two primary questions; first, what is the scope and nature of protection afforded to the collective dimension of freedom of religion or belief in international law, and, secondly, how does the protection of the collective dimension of freedom of religion or belief in Turkey compare and contrast to international standards? Section I explores and examines the notion of the collective dimension of freedom of religion or belief, and the scope of its protection in international law with particular reference to the right to acquire legal personality and autonomy religious/belief communities. In Section II, the case study on Turkey constitutes the applied part of the thesis; here, the protection of the collective dimension is assessed with a view to evaluate the compliance of Turkish legislation and practice with international norms as well as seeking to identify how the standard of international review of the collective dimension of freedom of religion or belief can be improved.

Return and Volatility spillovers among stock and Foreign Exchange Markets: Empirical Evidence from selected African Markets

Return and volatility dynamics in financial markets across the world have recently become important for the purpose of asset pricing, portfolio allocation and risk management. However, volatility, which come about as a result of the actions of market participants can help adapt to different situations and perform when it really matters. With recent development and liberalization among financial markets in emerging and frontier markets, the need for how the equity and foreign exchange markets interact and the extent to which return and volatility spillover are spread across countries is of importance to investors and policy makers at large. Financial markets in Africa have received attention leading to investors diversifying into them in times of crisis and contagion effects in developed countries. Regardless of the benefits these markets may offer, investors must be wary of issues such as thin trading, volatility that exists in the equity and currency markets and its related fluctuations. The study employs a VAR-GARCH BEKK model to study the return and volatility dynamics between the stock and foreign exchange sectors and among the equity markets of Egypt, Kenya, Nigeria, South Africa and Tunisia. The main findings suggest a higher dependence of own return in the stock markets and a one way return spillover from the currencies to the equity markets except for South Africa which has a weaker interrelation among the two markets. There is a relatively limited integration among the equity markets. Return and volatility spillover is mostly uni-directional except for a bi-directional relationship between the equity markets of Egypt and Tunisia. The study implication still proves a benefit for portfolio managers diversifying in these African equity markets, since they are independent of each other and may not be highly affected by the influx of negative news from elsewhere. However, there is the need to be wary of return and volatility spillover between the equity and currency markets, hence devising better hedging strategies to curb them.

Innovatiivisen virtuaaliyhteisön edellytykset

Tutkielmassa tutkittiin innovatiivisen virtuaaliyhteisön toiminnan edellytyksiä. Teoreettinen viitekehys muodostui virtuaaliyhteisöjen, innovatiivisuuden ja luovuuden tarkastelusta. Tutkielman empiirisessä osuudessa käytettiin kvalitatiivista tutkimusotetta. Tutkimusaineisto perustui internetiin tutkimusta varten perustetun innovointiin keskittyneen keskustelufoorumin tuottamiin tuloksiin sekä ko. foorumin käyttäjien palautteeseen. Tutkimuksessa kävi ilmi, että innovatiivisuus vaatii motivoitumista käsiteltävään aiheeseen. Ideoijan täytyy kokea aihe mielenkiintoiseksi, jotta virtuaaliyhteisössä tapahtuva innovointi pystyy tarjoamaan parhaan etunsa eli välineen ajasta ja paikasta riippumattomaan ideointiin. Virtuaaliyhteisöllä tulee olla koordinaattori, joka pitää huolen tiedon kokoamisesta, yhteenvedoista ja ruokkii yhteisön aktiivisuutta. Yhteisössä innovoiminen edellyttää yhteisön ilmapiirin rakentamista otolliseksi avoimelle viestinnälle. Tämä syntyy rakentamalla luottamusta toimijoiden välille mm. kannustamalla sosiaaliseen viestintään. Virtuaaliyhteisössä passivoituminen on suuri uhka. Virtuaaliyhteisöä täytyy johtaa kannustaen ja pitäen kaikin keinoin huolta jäsenten aktiivisen keskustelun ylläpidosta. Passiivisuus aiheuttaa yleistä passiivisuutta, aktiivisuus nostaa aktiivisuutta. Toimijoiden anonyymius voi olla yhteisön voimavara, mutta tuo sitoutumattomuutta, jolloin mikä tahansa häiritsevä tekijä saa aikaan sen, että toimija voi jättää osallistumatta asian käsittelyyn ilman muualta kohdistuvia paineita. Anonyymiyden hyödyt ja haitat tulee punnita tarkoin.

Valuuttasuojaus kansainvälisissä osakeportfolioissa - eurosijoittajan näkökulma

Tämän tutkimuksen tarkoituksena on selvittää eurosijoittajan näkökulmasta tehokkain strategia kansainvälisen osakeportfolion valuuttariskin suojaamiseen. Tutkimuksessa tarkastellaan akateemisissa tutkimuksissa eniten käsiteltyjä valuuttasuojausstrategioita ja pyritään tunnistamaan niistä tieteellisesti valideimmat metodit tutkimuksen empiiriseen osioon. Valuuttasuojauksen tehokkuutta tullaan mittaamaan niin riskin kuin tuoton näkökulmista. Empiirisessä osiossa käytetään aineistona kahdeksan eri valtion osakemarkkinaindeksien ja valuuttojen spot- ja termiinikurssien kuukausittaisia tuottoja niin, että tarkastelu tapahtuu euroalueen sijoittajan näkökulmasta. Tutkimuksen aikaväli on 31.12.2004 - 31.12.2010. Tutkimuksessa päädyttiin suosittamaan 50 % valuuttariskin suojausastetta eurosijoittajan näkökulmasta. Kyseinen strategia alensi parhaiten kansainvälisen sijoittajan portfolion riskiä tutkitulla aikavälillä, eikä strategia myöskään heikentänyt merkittävästi portfolion tuottoa. Absoluuttisella kumulatiivisella tuotolla mitattuna suojaamaton osakeportfolio oli tutkimuksen aikavälillä paras, johtuen pääosin vuoden 2010 eurokriisistä, jonka vuoksi euro heikentyi voimakkaasti muita valuuttoja vastaan. Ennen kriisiä ”selektiivinen” valuuttasuojausstrategia oli tuotoilla (sekä kumulatiivinen että riskikorjattu) mitattuna paras.

"Vain toimitusjohtaja voi ymmärtää toimitusjohtajaa" - käytäntöyhteisö uuden tiedon luomisessa

Tämän tutkimuksen tavoitteena on selvittää miten käytäntöyhteisö edistää tiedon jakamista ja uuden tiedon luomista. Tutkimus on laadullinen tapaustutkimus toimitusjohtajien keskinäisestä käytäntöyhteisöstä. Tutkimusaineisto on kerätty puolistrukturoiduilla haastatteluilla, lisäksi on hyödynnetty havainnointia ja kirjallista materiaalia. Aineisto on analysoitu abduktiivisesti sisällönanalyysimenetelmällä. Tutkimuksen tulosten mukaan käytäntöyhteisössä tietoprosessien edellytyksinä on sekä sosiaalisia ja vuorovaikutukseen liittyviä että tiedolliseen monimuotoisuuteen ja yhtenevään tietoperustaan liittyviä tekijöitä. Tulokset tuovat esiin mekanismeja tiedon jakamisen ja uuden tiedon luomisen edistämiseksi käytäntöyhteisöissä. Käytäntöyhteisöön osallistumista ohjaavat pääasiassa sisäiset motiivit, joista korostuivat vertaistuki, verkostoituminen ja informaation vaihto. Osa sisäisistä hyödyistä johtaa toisiin sisäisiin hyötyihin ja osa myös ulkoisiin hyötyihin.