Dancing and Professional Dancers in Roman Egypt

The main aim of the study is to create a many-sided view of dancing in Roman Egypt (1st - early 4th centuries AD) and especially of the dancers who earned their living by dancing as hired performers. Even though dancers and other performers played a central part in many kinds of festivities throughout the ancient world, research on ancient professional dancers is rare and tends to rest on the ancient literature, which reflects the opinions of the elite. Documentary written sources (i.e., papyri, ostraka) the core of the present study are mentioned rather superficially, easily resulting in a stereotypical view of the dancers. This study will balance the picture of professional dancers in antiquity and of ancient dancing in a more general sense. The second aim characterizes this study as basic research: to provide a corpus of written sources from Greco-Roman Egypt on dancing and to discuss pictorial sources contemporary with the texts. The study also takes into account the theoretical discussion that centres on dancing as a nonverbal communicative mode. Dancers are seen as significant conveyors of social and cultural matters. This study shows that dancers were hired to perform especially in religious contexts, where the local associations on the village level also played an important part as the employers of the performers. These performers had a better standard of living in economic terms than the average hired worker, and dancers were better paid than other performers. In the Egyptian villages and towns, where the dancers performed and lived, the dancers do not seem to have been marginal because they were professionals or because of some ethnic or social background. However, their possible marginality may have occurred for reasons related to the practicalities of their profession (e.g., the itinerant life style). The oriental background of performers was a literary topos reflecting partly the situation in the centres of the empire, especially Rome, where many performers were of other than Roman origin. The connection of dancing, prostitution and slavery reflects the essential link between dance, body and gender: dancers are equated with such professions or socio-legal statuses where the body is the focus of attention, a commodity and a source of sensual pleasure; this dimension is clearly observable in ancient literature. According to the Egyptian documentary sources, there is no watertight evidence that professional dancers would have been engaged in prostitution and very little, if any, evidence that the disapproval of the professional dancers expressed by the ancient authors was shared by the Egyptians. From the 4th century onwards the dancers almost disappear from the documentary sources, reflecting the political and religious changes in the Mediterranean east.

Coordinated Verb Pairs in Texts

This dissertation discusses the relation between lexis, grammar and textual organisation. The major premise adopted here is that grammatical structures are motivated both by semantic potential of words and by text-pragmatic demands. In other words, it is argued that grammatical structures form the interface between lexis and textual organisation, and that linguistic analysis should not concentrate on analysing grammatical structures in isolation, independent of context. From this point of view, grammatical structures are said to be 'well-formed' only in relation to the context they occur in. This study is based on a corpus of three million words of recent Finnish fiction from which all the occurrences of the coordinated verb pairs ([V ja V] -pairs]) containing one of the intransitive motion verbs 'lähteä' (to go), 'mennä' (to go), 'päästä' (to get into), 'nousta' (to get up), and 'laskea' (to go down), were extracted. This set of verbs was established using methods described in earlier work by Lagus & Airola (2001, and 2005). The quantitative analysis of the [V ja V] -pairs was used to carry out a qualitative analysis of individual texts. In analysing the texts, an analogy was made between musical and textual structure. The results show among others that individual verbs specialise in different functions when occurring in coordinated verb pairs. One aspect was that those verb pairs including the verb 'nousta' tend to function as markers of textual boundaries and thus reflect the organisation of narrative substance. The verb 'mennä' has weakened literal meanings, but strengthened modal meanings when occurring in [V ja V] -pairs, and, in many cases, the verb 'lähteä' in [V ja V] -pairs function as an aspectual marker rather than a pure verb of motion. That there is a gradient from the concrete sense of motion into more differentiated senses of a verb in [V ja V] -pairs alongside the structure-creating potential of the [V ja V] -pairs themselves suggest an ongoing grammaticalisation process of the patterns discussed.

Reconsidering Relativism and Intentionalism in Interpretation : Donald Davidson, Hermeneutics, and Pragmatism

This study focuses on two philosophical issues related to the interpretation of art. Firstly, it considers the role of authorial intentions in interpretation. Secondly, the study raises the issue of relativism in interpretation through a discussion of the relativistic tendencies apparent in the views of three major figures of contemporary philosophy: Joseph Margolis, Hans-Georg Gadamer, and Richard Rorty. The major goal of the thesis is to develop a theory of interpretation supporting the role of authorial intentions in interpretation on the basis of Donald Davidson s late philosophy of language and the holistic account of interpretation that underlies different parts of his philosophy. It is my belief that an intentionalist view of interpretation built on Davidsonian elements manages to form the most convincing defense of that interpretive position against the skepticism present in the views of Margolis, Gadamer, and Rorty. The theoretical issues addressed in the thesis are illuminated by discussions of case-examples, most importantly Richard Wagner s The Valkyrie, Thomas Adés America: A Prophecy, and some symphonies by Dimitri Shostakovich. In chapter one, I present a critical discussion of Margolis robust relativism. While finding Margolis criticism of the self-refutive argument plausible, I, nevertheless, argue that the relativistic logic Margolis offers should not be favored in interpretation. The first parts of chapter two outline Davidsonian intentionalism by presenting a reading of Davidson s later work in philosophy of language and mind, and by indicating its relationship to Davidson s views of literature. Then, I shall compare Davidson s ideas with some recent modest forms of intentionalism found in analytic aesthetics, and argue that Davidsonian intentionalism is in many respects more satisfactory compared to them. Chapter three engages Gadamer s hermeneutics by defending E.D. Hirsch s criticism of Gadamer. Uncovering the shortcomings in the replies of Gadamer s followers to Hirsch s criticism serves as a basis for the defense of intentionalism in interpretation carried out in the chapter. That defense is then extended with a discussion of some recent hermeneutic readings of Davidson s views. Chapter four deals with the standing of intentionalism through Rorty s pragmatist approach to literature. By indicating the position of pragmatist notions of aesthetic experience and imagination in Davidsonian intentionalism, it is shown that an intentionalist approach need not be as impoverished with regard to the value Rorty attributes to literature as he assumes. The concluding chapter outlines some ways in which one can be a pluralist with regard to art and interpretation without falling into relativism.

Society by Numbers : Studies on Model-Based Explanations in the Social Sciences

The aim of this dissertation is to provide conceptual tools for the social scientist for clarifying, evaluating and comparing explanations of social phenomena based on formal mathematical models. The focus is on relatively simple theoretical models and simulations, not statistical models. These studies apply a theory of explanation according to which explanation is about tracing objective relations of dependence, knowledge of which enables answers to contrastive why and how-questions. This theory is developed further by delineating criteria for evaluating competing explanations and by applying the theory to social scientific modelling practices and to the key concepts of equilibrium and mechanism. The dissertation is comprised of an introductory essay and six published original research articles. The main theses about model-based explanations in the social sciences argued for in the articles are the following. 1) The concept of explanatory power, often used to argue for the superiority of one explanation over another, compasses five dimensions which are partially independent and involve some systematic trade-offs. 2) All equilibrium explanations do not causally explain the obtaining of the end equilibrium state with the multiple possible initial states. Instead, they often constitutively explain the macro property of the system with the micro properties of the parts (together with their organization). 3) There is an important ambivalence in the concept mechanism used in many model-based explanations and this difference corresponds to a difference between two alternative research heuristics. 4) Whether unrealistic assumptions in a model (such as a rational choice model) are detrimental to an explanation provided by the model depends on whether the representation of the explanatory dependency in the model is itself dependent on the particular unrealistic assumptions. Thus evaluating whether a literally false assumption in a model is problematic requires specifying exactly what is supposed to be explained and by what. 5) The question of whether an explanatory relationship depends on particular false assumptions can be explored with the process of derivational robustness analysis and the importance of robustness analysis accounts for some of the puzzling features of the tradition of model-building in economics. 6) The fact that economists have been relatively reluctant to use true agent-based simulations to formulate explanations can partially be explained by the specific ideal of scientific understanding implicit in the practise of orthodox economics.

Substrata Uralica : Studies on Finno-Ugrian Substrate in Northern Russian Dialects

The thesis consists of five articles and an introduction. It treats the problems of the Uralic substrate, most notably, the substrate toponyms, in the Russian dialects of Arkhangelsk region. The articles contribute to the general linguistic discussion concerning the nature of linguistic substrate and the outcome of language shift and to the onomastic discussion concerning the etymologisation and ethnic interpretation of substrate toponymy. Among the questions the articles scrutinised are the following: 1) How may phonetic and morphosyntactic substrate interference be verified? 2) How typical is the transfer of vocabulary in the case of a language shift? 3) How the borrowing of toponymy and appellative vocabulary are connected in the case of a language shift? 4) How does the etymologisation of the toponyms differ from the etymologisation of appellatives? 5) How reliable can the toponymic etymologies be? 6) How can the substrate language be identified? It is found that the substrate interference that can be meaningfully studied, from the point of view of historical linguistics, is predominantly lexical and not related to phonetics and morphosyntax, as presumed in many handbooks. New methods are outlined for the identification of substrate languages separately from the lexical, phonological and typological point of view by using the substrate toponymy as the main source of information on extinct languages. A reliability scale for the toponymic etymologies is developed that helps to identify the kinds of etymologies containing ethnohistorically meaningful information. The study also sheds light on questions related to Uralistics and Slavistics. The most important of these are the following: 1) Which Uralic languages were spoken in North Russia prior to Slavic? 2) When did the Slavicisation of the Finno-Ugrian population take place in the area of the Arkhangelsk Region? 3) What is the significance of the Finno-Ugrian substrate in northern Russian dialects to comparative Uralistics? 4) Are there any traces of pre-Uralic substrate languages in north-eastern Europe? The Finnic substrate languages, already identified by earlier studies, seem to have consisted of two groups, one of which was closest to the southern Finnic. Also, language(s) close to Sámi in some respects though not identical with it where spoken in pre-Slavic North Russia.

Exploring Problem Decomposition in Conceptual Design

Design embraces several disciplines dedicated to the production of artifacts and services. These disciplines are quite independent and only recently has psychological interest focused on them. Nowadays, the psychological theories of design, also called design cognition literature, describe the design process from the information processing viewpoint. These models co-exist with the normative standards of how designs should be crafted. In many places there are concrete discrepancies between these two in a way that resembles the differences between the actual and ideal decision-making. This study aimed to explore the possible difference related to problem decomposition. Decomposition is a standard component of human problem-solving models and is also included in the normative models of design. The idea of decomposition is to focus on a single aspect of the problem at a time. Despite its significance, the nature of decomposition in conceptual design is poorly understood and has only been preliminary investigated. This study addressed the status of decomposition in conceptual design of products using protocol analysis. Previous empirical investigations have argued that there are implicit and explicit decomposition, but have not provided a theoretical basis for these two. Therefore, the current research began by reviewing the problem solving and design literature and then composing a cognitive model of the solution search of conceptual design. The result is a synthetic view which describes recognition and decomposition as the basic schemata for conceptual design. A psychological experiment was conducted to explore decomposition. In the test, sixteen (N=16) senior students of mechanical engineering created concepts for two alternative tasks. The concurrent think-aloud method and protocol analysis were used to study decomposition. The results showed that despite the emphasis on decomposition in the formal education, only few designers (N=3) used decomposition explicitly and spontaneously in the presented tasks, although the designers in general applied a top-down control strategy. Instead, inferring from the use of structured strategies, the designers always relied on implicit decomposition. These results confirm the initial observations found in the literature, but they also suggest that decomposition should be investigated further. In the future, the benefits and possibilities of explicit decomposition should be considered along with the cognitive mechanisms behind decomposition. After that, the current results could be reinterpreted.

Stem Cell Markers in Cancer: Do They Have Clinical Significance?

In cancer, a subpopulation of malignant cells expresses markers of normal stem cells. These cells have the potential of initiating tumor growth and therefore also tumor recurrence. Thus, these cells are called cancer stem cells. A myriad of markers have been applied to identify these cells, but no single marker can be found exclusively in cancer stem cells. In many types of cancer, clinical recurrence and tumor progression are the main causes of mortality, despite intense oncological treatment. It has been proposed that the presence of cancer stem cells causes this resistance to therapy. The scope of this thesis is to investigate the role of stem cell markers and genes in the clinical setting. Especially, the aim was to elucidate the clinical significance of stem cell markers as novel prognostic and diagnostic tools in cancer. Tumor biopsy material from central nervous system tumors (oligodendroglioma, astrocytoma and glioblatoma), neural crest derived tumors (pheochromocytomas) and oral carcinoma was screened for stem cell markers. Initially, 15 stem cell markers were screened in a test series of gliomas. The markers applied for expanded tumor analyses (in 305 cases of glioma, 42 cases of pheochromocytoma, and 73 cases of oral carcinoma) were BMI-1, Snail, p16, mdm2, and c-Myc. Data on marker expression was compared with clinical and pathological parameters. In gliomas, BMI-1 expression was found in nearly all tumors analyzed, but the frequency of BMI-1 expressing cells was highly variable, ranging from 1 to 100%. In oligodendroglioma, BMI-1 expression was identified as a prognostic marker independent of tumor grade and clinical parameters. In pheochromocytoma, Snail expression was shown to distinguish between the metastatic and non-metastatic forms of the tumor. Snail expression was seen only in metastatic tumors, whereas non-metastatic tumors did not commonly express Snail. Finally, in oral carcinoma, BMI-1 expression was seen in roughly 80% of tumors, and Snail expression was high or very high in all cases. The lack of BMI-1 expression was associated with early relapse in oral carcinoma.

Of tolerance in mice and men : studies in APECED and Aire

Autoimmune diseases affect 5 % of the population and come in many forms, such as diabetes, rheumatoid arthritis and MS. However, how and why autoimmune diseases arise are not yet fully resolved. In this thesis, the onset of autoimmunity was investigated using both patient samples and a mouse model of autoimmunity. Autoimmune diseases are usually complex, due to a number of different causative genes and environmental factors. However, a few monogenic autoimmune diseases have been described, which are caused by mutations in only one gene per disease. One of such disease is called APECED (autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy) and is enriched in the Finnish population. The causative gene behind APECED is named AIRE from AutoImmune REgulator. How malfunction of just one gene product can cause the multitude of disease components found in APECED is not yet resolved. This thesis sought out to find out more about the functions of AIRE, in order to reveal why APECED and other autoimmune diseases arise and what goes wrong? Usually, immune cells are taught to distinguish between self and non-self during their development. That way, immune cells can fight off bacteria and microbes while leaving the tissues and organs of the host organism itself unharmed. In APECED, the development of immune cells called αβ T cells is incomplete. The cells are not able to fully distinguish between self and non-self. This leads to autodestruction of self tissues and autoimmune disease. One of the achievements of this thesis was the finding that the development of another set of T cells called γδ T cells is not affected by AIRE in mice or in men. Instead, we found that another type of immune cell important in tolerance, called the dendritic cell is defective in APECED patients and is not able to respond to microbial stimulus in a normal fashion. Finally, we studied Aire-deficient mice and found that autoantibodies expressed in the mice were not targeted against the same molecules as those found in APECED patients. This indicates differences in the autoimmune pathology in mice and men. More work is still required before we understand the mechanisms of tolerance and autoimmunity well enough to be able to cure APECED, let alone the more complex autoimmune diseases. Yet altogether, the findings of this thesis work bring us one step closer to finding out why and how APECED and common autoimmune diseases arise.

Periodontitis and peri-implantitis biomarkers in human oral fluids and the null-allele mouse model

Tissue destruction associated with the periodontal disease progression is caused by a cascade of host and microbial factors and proteolytic enzymes. Aberrant laminin-332 (Ln-332), human beta defensin (hBD), and matrix metalloproteinase (MMP) functions have been found in oral inflammatory diseases. The null-allele mouse model appears as the next step in oral disease research. The MMP-8 knock-out mouse model allowed us to clarify the involvement of MMP-8 in vivo in oral and related inflammatory diseases where MMP-8 is suggested to play a key role in tissue destruction. The cleaved Ln-332 γ2-chain species has been implicated in the apical migration of sulcular epithelial cells during the formation of periodontal pockets. We demonstrated that increased Ln-332 fragment levels in gingival crevicular fluid (GCF) are strongly associated with the severity of inflammation in periodontitis. Porphyromonas gingivalis trypsin-like proteinase can cleave an intact Ln-332 γ2-chain into smaller fragments and eventually promote the formation of periodontal pockets. hBDs are components of an innate mucosal defense against pathogenic microbes. Our results suggest that P. gingivalis trypsin-like proteinase can degrade hBD and thus reduce the innate immune response. Elevated levels and the increased activity of MMPs have been detected in several pathological tissue-destructive conditions where MMPs are shown to cleave extracellular matrix (ECM) and basement membrane (BM) molecules and to facilitate tissue destruction. Elevated levels of MMP-8 have been reported in many inflammatory diseases. In periodontitis, MMP-8 levels in gingival crevicular fluid (GCF) and in peri-implant sulcular fluid (PISF) are elevated at sites of active inflammation, and the increased levels of MMP-8 are mainly responsible for collagenase activity, which leads to tissue destruction. MMP-25, expressed by neutrophils, is involved in inflammatory diseases and in ECM turnover. MMP-26 can degrade ECM components and serve as an activator of other MMP enzymes. We further confirmed that increased levels and activation of MMP-8, -25, and -26 in GCF, PISF, and inflamed gingival tissue are associated with the severity of periodontal/peri-implant inflammation. We evaluated the role of MMP-8 in P. gingivalis-induced periodontitis by comparing MMP-8 knock-out (MMP8-/-) and wild-type mice. Surprisingly, MMP-8 significantly attenuated P. gingivalis-induced site-specific alveolar bone loss. We also evaluated systemic changes in serum immunoglobulin and lipoprotein profiles among these mouse groups. P. gingivalis infection increased HDL/VLDL particle size in the MMP-8-/- mice, which is an indicator of lipoprotein responses during systemic inflammation. Serum total LPS and IgG antibody levels were enhanced in both mice groups. P. gingivalis-induced periodontitis, especially in MMP-8-/- mice, is associated with severe alveolar bone loss and with systemic inflammatory and lipoprotein changes that are likely to be involved in early atherosclerosis.

Methicillin Resistance In Staphylococci : Horizontal Transfer of Mobile Genetic Element (SCCmec) Between Staphylococcal Species

Regardless of the existence of antibiotics, infectious diseases are the leading causes of death in the world. Staphylococci cause many infections of varying severity, although they can also exist peacefully in many parts of the human body. Most often Staphylococcus aureus colonises the nose, and that colonisation is considered to be a risk factor for spread of this bacterium. S. aureus is considered to be the most important Staphylococcus species. It poses a challenge to the field of medicine, and one of the most problematic aspects is the drastic increase of the methicillin-resistant S. aureus (MRSA) strains in hospitals and community world-wide, including Finland. In addition, most of the clinical coagulase-negative staphylococcus (CNS) isolates express resistance to methicillin. Methicillin-resistance in S. aureus is caused by the mecA gene that encodes an extra penicillin-binding protein (PBP) 2a. The mecA gene is found in a mobile genomic island called staphylococcal chromosome cassette mec (SCCmec). The SCCmec consists of the mec gene and cassette chromosome recombinase (ccr)gene complexes. The areas of the SCCmec element outside the ccr and mec complex are known as the junkyard J regions. So far, eight types of SCCmec(SCCmec I- SCCmec VIII) and a number of variants have been described. The SCCmec island is an acquired element in S. aureus. Lately, it appears that CNS might be the storage place of the SCCmec that aid the S. aureus by providing it with the resistant elements. The SCCmec is known to exist only in the staphylococci. The aim of the present study was to investigate the horizontal transfer of SCCmec between the S. aureus and CNS. One specific aim was to study whether or not some methicillin-sensitive S. aureus (MSSA) strains are more inclined to receive the SCCmec than others. This was done by comparing the genetic background of clinical MSSA isolates in the health care facilities of the Helsinki and Uusimaa Hospital District in 2001 to the representatives of the epidemic MRSA (EMRSA) genotypes, which have been encountered in Finland during 1992-2004. Majority of the clinical MSSA strains were related to the EMRSA strains. This finding suggests that horizontal transfer of SCCmec from unknown donor(s) to several MSSA background genotypes has occurred in Finland. The molecular characteristics of representative clinical methicillin-resistant S. epidermidis (MRSE) isolates recovered in Finnish hospitals between 1990 and 1998 were also studied, examining their genetic relation to each other and to the internationally recognised MRSE clones as well, so as to ascertain the common traits between the SCCmec elements in MRSE and MRSA. The clinical MRSE strains were genetically related to each other; eleven PFGE types were associated with sequence type ST2 that has been identified world-wide. A single MRSE strain may possess two SCCmec types III and IV, which were recognised among the MRSA strains. Moreover, six months after the onset of an outbreak of MRSA possessing a SCCmec type V in a long-term care facility in Northern Finland (LTCF) in 2003, the SCCmec element of nasally carried methicillin-resistant staphylococci was studied. Among the residents of a LTCF, nasal carriage of MR-CNS was common with extreme diversity of SCCmec types. MRSE was the most prevalent CNS species. Horizontal transfer of SCCmec elements is speculated to be based on the sharing of SCCmec type V between MRSA and MRSE in the same person. Additionally, the SCCmec element of the clinical human S. sciuri isolates was studied. Some of the SCCmec regions were present in S. sciuri and the pls gene was common in it. This finding supports the hypothesis of genetic exchange happening between staphylococcal species. Evaluation of the epidemiology of methicillin-resistant staphylococcal colonisation is necessary in order to understand the apparent emergence of these strains and to develop appropriate control strategies. SCCmec typing is essential for understanding the emergence of MRSA strains from CNS, considering that the MR-CNS may represent the gene pool for the continuous creation of new SCCmec types from which MRSA might originate.

Agroforestry systems for sustainable livelihoods and improved land management in the East Usambara Mountains, Tanzania

Forest destruction for agriculture continues to be a major threat to the rich biological diversity in the East Usambara Mountains in the north-eastern corner of Tanzania. The highest ratio of endemic plant and animal species found on 100 km2 anywhere in the world is depending on the remaining natural forests. Forests are vitally important for the local population in many different ways, and nationally they are an important source of water and hydroelectricity. The soils, of low fertility and mostly acidic Ferrasols, mainly have the nutrients in the topsoil. After clear-cutting, the soils soon become poor when the topsoil is eroded. High-value cardamom is nowadays unsustainably cultivated in the natural forests of the East Usambaras. The general aim was to study the possibilities to develop new profitable and sustainable agroforestry systems for the benefit of the local people that could contribute to relieving the pressure on the remaining natural forests in the East Usambara Mountains. Results from a spice crop agroforestry trial, established in cooperation with a local farmer, showed a clear advantage of intercropping cardamom (Elettaria cardamomum) and black pepper (Piper nigrum) with trees, especially with Grevillea robusta. The nitrogen fixing tree species Gliricidia sepium also improved the nitrogen and organic matter content of the soil over levels found in the natural forest. With improved agroforestry methods for spice production the households generated as much as13 times the net income obtained with traditional forest cultivation practices. There are thus sustainable and profitable ways to cultivate spices as cash crops in well-managed homegardens. However, the farmers need stable markets, access to credit and comprehensive extension services. The soil fertility depletion should be reversed with organic manure application and an enabling policy environment for the smallholder-farming sector. Strong farmers organisations and equal rights to resources and decision-making are needed. Organic spices have an increasing demand, and their export would be profitable for these farmers. What is, however, most needed for a change is a political will of a government that understands the importance of agricultural and forestry development for poverty reduction.

Burnt area mapping in insular Southeast Asia using medium resolution satellite imagery

Burnt area mapping in humid tropical insular Southeast Asia using medium resolution (250-500m) satellite imagery is characterized by persisting cloud cover, wide range of land cover types, vast amount of wetland areas and highly varying fire regimes. The objective of this study was to deepen understanding of three major aspects affecting the implementation and limits of medium resolution burnt area mapping in insular Southeast Asia: 1) fire-induced spectral changes, 2) most suitable multitemporal compositing methods and 3) burn scars patterns and size distribution. The results revealed a high variation in fire-induced spectral changes depending on the pre-fire greenness of burnt area. It was concluded that this variation needs to be taken into account in change detection based burnt area mapping algorithms in order to maximize the potential of medium resolution satellite data. Minimum near infrared (MODIS band 2, 0.86μm) compositing method was found to be the most suitable for burnt area mapping purposes using Moderate Resolution Imaging Spectroradiometer (MODIS) data. In general, medium resolution burnt area mapping was found to be usable in the wetlands of insular Southeast Asia, whereas in other areas the usability was seriously jeopardized by the small size of burn scars. The suitability of medium resolution data for burnt area mapping in wetlands is important since recently Southeast Asian wetlands have become a major point of interest in many fields of science due to yearly occurring wild fires that not only degrade these unique ecosystems but also create regional haze problem and release globally significant amounts of carbon into the atmosphere due to burning peat. Finally, super-resolution MODIS images were tested but the test failed to improve the detection of small scars. Therefore, super-resolution technique was not considered to be applicable to regional level burnt area mapping in insular Southeast Asia.

Tree mortality and deadwood dynamics in late-successional boreal forests

Here I aimed at quantifying the main components of deadwood dynamics, i.e. tree mortality, deadwood pools, and their decomposition, in late-successional boreal forests. I focused on standing dead trees in three stand types dominated by Picea mariana and Abies balsamea in eastern Canada, and on standing and down dead trees in Picea abies-dominated stands in three areas in Northern Europe. Dead and living trees were measured on five sample plots of 1.6-ha size in each study area and stand type. Stem disks from dead trees were sampled to determine wood density and year of death, using dendrochronological methods. The results were applied to reconstruct past tree mortality and to model deadwood decay class dynamics. Site productivity, stand developmental stage, and the occurrence of episodic tree mortality influenced deadwood volume and quality. In all study areas tree mortality was continuous, leading to continuity in deadwood decay stage distribution. Episodic tree mortality due to either autogenic or allogenic causes influenced deadwood volume and quality in all but one study area. However, regardless of productivity and disturbance history deadwood was abundant, accounting for 20 53% of total wood volume in European study areas, and 15 27% of total standing volume in eastern Canada. Deadwood was a persistent structural component, since its expected residence time in early- and midstages of decay was 18 yr even in the area with the most rapid decomposition. The results indicated that in the absence of episodic tree mortality, stands may eventually develop to a steady state, in which deadwood volume fluctuates around an equilibrium state. However, in many forests deadwood is naturally variable, due to recurrent moderate-severity disturbances. This variability, the continuous tree mortality, and variation in rates of wood decomposition determine the dynamics and availability of deadwood as a habitat and carbon storage medium in boreal coniferous forest ecosystems.

The efficacy and potential risks of controlling sprouting in Finnish birches (Betula spp.) with the fungal decomposer Chondrostereum purpureum

Sprouting of fast-growing broad-leaved trees causes problems in young coniferous stands, under power transmission lines and along roads and railways. Public opinion and the Finnish Forest Certification System oppose the use of chemical herbicides to control sprouting, which means that most areas with problems rely on mechanical cutting. However, cutting is a poor control method for many broad-leaved species because the removal of leaders can stimulate the sprouting of side branches and cut stumps quickly re-sprout. In order to be effective, cutting must be carried out frequently but each cut increases the costs, making this control method increasingly difficult and expensive once begun. As such, alternative methods for sprout control that are both effective and environmentally sound represent a continuing challenge to managers and research biologists. Using biological control agents to prevent sprouting has been given serious consideration recently. Dutch and Canadian researchers have demonstrated the potential of the white-rot fungus Chondrostereum purpureum (Pers. ex Fr.) Pouzar as a control agent of stump sprouting in many hardwoods. These findings have focused the attention of the Finnish forestry community on the utilization of C. purpureum for biocontrol purposes. Primarily, this study sought determines the efficacy of native C. purpureum as an inhibitor of birch stump sprouting in Finland and to clarify its mode of action. Additionally, genotypic variation in Finnish C. purpureum was examined and the environmental risks posed by a biocontrol program using this fungus were assessed. Experimental results of the study demonstrated that C. purpureum clearly affects the sprouting of birch: both the frequency of living stumps and the number of living sprouts per stump were effectively reduced by the treatment. However, the treatment had no effect on the maximum height of new sprouts. There were clear differences among fungal isolates in preventing sprouting and those that possessed high oxidative activities as measured in the laboratory inhibited sprouting most efficiently in the field. The most effective treatment time during the growing season was in early and mid summer (May July). Genetic diversity in Nordic and Baltic populations of C. purpureum was found to be high at the regional scale but locally homogeneous. This natural distribution of diversity means that using local genotypes in biocontrol programs would effectively prevent the introduction of novel genes or genotypes. While a biocontrol program using local strains of C. purpureum would be environmentally neutral, pruned birches that are close to the treatment site would have a high susceptibility to infect by the fungus during the early spring.

Uncertainty in forest simulators and forest planning systems

The forest simulator is a computerized model for predicting forest growth and future development as well as effects of forest harvests and treatments. The forest planning system is a decision support tool, usually including a forest simulator and an optimisation model, for finding the optimal forest management actions. The information produced by forest simulators and forest planning systems is used for various analytical purposes and in support of decision making. However, the quality and reliability of this information can often be questioned. Natural variation in forest growth and estimation errors in forest inventory, among other things, cause uncertainty in predictions of forest growth and development. This uncertainty stemming from different sources has various undesirable effects. In many cases outcomes of decisions based on uncertain information are something else than desired. The objective of this thesis was to study various sources of uncertainty and their effects in forest simulators and forest planning systems. The study focused on three notable sources of uncertainty: errors in forest growth predictions, errors in forest inventory data, and stochastic fluctuation of timber assortment prices. Effects of uncertainty were studied using two types of forest growth models, individual tree-level models and stand-level models, and with various error simulation methods. New method for simulating more realistic forest inventory errors was introduced and tested. Also, three notable sources of uncertainty were combined and their joint effects on stand-level net present value estimates were simulated. According to the results, the various sources of uncertainty can have distinct effects in different forest growth simulators. The new forest inventory error simulation method proved to produce more realistic errors. The analysis on the joint effects of various sources of uncertainty provided interesting knowledge about uncertainty in forest simulators.