The decline of northern malaria and population dynamics of Plamodium vivax

Europe was declared malaria free in 1975. The disappearance of malaria has traditionally been attributed to numerous deliberate actions like vector control, the screening of houses, more efficient medication etc. Malaria, however, disappeared from many countries like Finland before any counter measures had even started. The aim of this thesis is to study the population ecology of P. vivax and its interaction with the human host and the vector. By finding the factors that attributed to the extinction of vivax malaria it might be possible to improve the modern strategy against P. vivax. The parasite was studied with data from Finland, which provides the longest time series (1749-2008) of malaria statistics in the world. The malaria vectors, Anopheles messeae and A. beklemishevi are still common species in the country. The eradication of vivax malaria is difficult because the parasite has a dormant stage that can cause a relapse long after a primary infection. It was now shown that P. vivax is able to detect the presence of a potential vector. A dormant stage is triggered even from a bite of an uninfected Anopheles mosquito. This optimizes the chances for the Plasmodium to reach a mosquito vector for sexual reproduction. The longevity of the dormant stage could be shown to be at least nine years. The parasite spends several years in its human host and the behaviour of the human carrier had a profound impact on the decline of the disease in Finland. Malaria spring epidemics could be explained by a previous warm summer. Neither annual nor summer mean temperature had any impact on the long term malaria trend. Malaria disappeared slowly from Finland without mosquito control. The sociological change from extended families to nuclear families led to decreased household size. The decreased household size correlated strongly with the decline of malaria. That led to an increased isolation of the subpopulations of P. vivax. Their habitat consisted of the bedrooms in which human carriers slept together with the overwintering vectors. The isolation of the parasite ultimately led to the extinction of vivax malaria. Metapopulation models adapted to local conditions should therefore be implemented as a tool for settlement planning and socio-economic development and become an integrated part of the fight against malaria.

Skogsbränslets elementära sammansättning med tanke på förbränningsprocessen och för näringsämnesförluster i ekosystemet

There are several reasons for increasing the usage of forest biomass for energy in Finland. Apart from the fact that forest biomass is a CO2 -neutral energy source, it is also a domestic resource distributed throughout the country. Usage of forest biomass in the form of logging residues decreases Finland’s dependence of energy import and increases both incomes and employment. Wood chips are mainly made from logging residues, which constitute 64 % of the raw material. A large-scale use of forest biomass requires heed also to the potential negative aspects. Forest bioenergy is used extensively, but its impacts on the forests soil nutrition and carbon balance has not been studied much. Nor have there been many studies on the heavy metal or chlorine content of logging residues. The goal of this study was to examine the content of carbon, macronutrients, heavy metals and other for the combustion harmful substances in Scots pine and Norway spruce wood chips, and to estimate the effect of harvesting of logging residues on the forests carbon and nutrient balance. Another goal was to examine the energy content of the clear cut remains. The Wood chips for this study were gathered from pine and spruce dominated clear cut sites in southern Finland, in the costal forests between Hankoo and Siuntio. The number of sample locations were 29, and the average area was 3,15 ha and the average timber volume 212,6 m3 ha -1. The average logged timber volume was for Scots pine timber 70 m3 ha -1 and for Norway spruce timber 124 m3 ha -1 and for deciduous timber (birch and alder) 18,5 m3 ha -1. The proportion of spruce in the logging residues and the stand-volume were relevant for how much nutrients were taken from the forest ecosystem when harvesting logging residues. In this study it was noted that the nutrient content of the logging residues clearly increased when the percentage of spruce in the timber volume increased. The S, K, Na and Cl -contents in the logging residues in this study increased with an increasing percentage of spruce, which is probably due to the fact that the spruce is an effective collector of atmospheric dry-deposition. The amounts of nutrients that were lost when harvesting logging residues were less than those referred to in the literature. Within a circulation period (100 years), the forest soil gets substantially more nutrients from atmospheric deposition, litter fall and weathering than is lost through harvesting of logging residues after a clear cut. Harvesting of the logging residues makes for a relatively modest increase of the quantity of carbon that is removed from the forest compared to traditional forestry. Due to the fact that the clear cut remains in my study showed a high content of chlorine, there is a risk of corrosion in connection to the incineration of the logging residues in power plants especially at coastal areas/forests. The risk of sulphur -related corrosion is probably rather small, because S concentrations are relatively low in woodchips. The clear cut remains showed rather high heavy metal contents. If the heavy metal contents in this study are representative for the clear cut remains in the coastal forests generally, there might be reason to exert some caution when using the ash for forest fertilizing purposes.

Suunnittelunäkemys metsäorganisaatioissa ja sen vaikutus tietojärjestelmälle asetettaviin vaatimuksiin

Department of Forest Resource Management in the University of Helsinki has in years 2004?2007 carried out so-called SIMO -project to develop a new generation planning system for forest management. Project parties are organisations doing most of Finnish forest planning in government, industry and private owned forests. Aim of this study was to find out the needs and requirements for new forest planning system and to clarify how parties see targets and processes in today's forest planning. Representatives responsible for forest planning in each organisation were interviewed one by one. According to study the stand-based system for managing and treating forests continues in the future. Because of variable data acquisition methods with different accuracy and sources, and development of single tree interpretation, more and more forest data is collected without field work. The benefits of using more specific forest data also calls for use of information units smaller than tree stand. In Finland the traditional way to arrange forest planning computation is divided in two elements. After updating the forest data to present situation every stand unit's growth is simulated with different alternative treatment schedule. After simulation, optimisation selects for every stand one treatment schedule so that the management program satisfies the owner's goals in the best possible way. This arrangement will be maintained in the future system. The parties' requirements to add multi-criteria problem solving, group decision support methods as well as heuristic and spatial optimisation into system make the programming work more challenging. Generally the new system is expected to be adjustable and transparent. Strict documentation and free source code helps to bring these expectations into effect. Variable growing models and treatment schedules with different source information, accuracy, methods and the speed of processing are supposed to work easily in system. Also possibilities to calibrate models regionally and to set local parameters changing in time are required. In future the forest planning system will be integrated in comprehensive data management systems together with geographic, economic and work supervision information. This requires a modular method of implementing the system and the use of a simple data transmission interface between modules and together with other systems. No major differences in parties' view of the systems requirements were noticed in this study. Rather the interviews completed the full picture from slightly different angles. In organisation the forest management is considered quite inflexible and it only draws the strategic lines. It does not yet have a role in operative activity, although the need and benefits of team level forest planning are admitted. Demands and opportunities of variable forest data, new planning goals and development of information technology are known. Party organisations want to keep on track with development. One example is the engagement in extensive SIMO-project which connects the whole field of forest planning in Finland.

The diet of the dingo (Canis lupus dingo and hybrids) in north-eastern Australia: a supplement to the paper of Brook and Kutt (2011)

Dingoes and other wild dogs (Canis lupus dingo and hybrids) are generalist predators that consume a wide variety of different prey species within their range. Little is known, however, of the diets of dingoes in north-eastern Australia where the potential for impacts by dingoes exists. Recently new information has been provided on the diets of dingoes from several sites in Queensland, Australia, significantly adding to the body of published knowledge on ecosystems within this region. Further information on the diet of dingoes in north-eastern Australia is added from 1460 scats collected from five sites, representing tropical savannahs, tropical offshore islands (and a matched mainland area), dry sclerophyll forests and peri-urban areas on the fringe of Townsville. Macropods, possums and bandicoots were found to be common prey for dingoes in these areas. Evidence suggested that the frequency of prey remains in scats can be an unreliable indicator of predation risk to potential prey and it was found that novel and unexpected prey species appear in dingo diets as preferred prey become unavailable. The results support the generalisation that dingoes prefer medium- to large-sized native prey species when available but also highlight the capacity for dingoes to exploit populations of both large and small prey species that might not initially be considered at risk from predation based solely on data on scats.

Merestä Metsäksi - yhteistoimintaverkostohankkeen sosiaaliset ja taloudelliset vaikutukset

The object of this study was to find out which factors made landowners interested in From Sea to Forest co-operation network. Co-operation networks protect biodiversity across boundaries and among groups of landowners with different kind of protection contracts. The social effects of From Sea to Forest - project are studied by analyzing the experience of co-operation and trust. Furthermore the possibility to influence decision making when choosing the pilot areas and doing the contracts was surveyed. Economical effects are estimated for those landowners, who signed a protection contract for ten years. The study is part of The Finnish Forest Research Institute s Ecological considerations in landscape-level collaborative planning of private forestry project. The material of the study comprises 13 interviews done in January 2006; seven interviewed were landowners and six forest professionals. The interviews were transcripted and analyzed with Atlas.ti programme. The economical effects were estimated with MOTTI forest simulation programme. From Sea to Forest project interested the landowners for similar reasons: the voluntariness of participation, compensation, fixed-term contracts and the possibility to protect forests so that the proprietary right remains. It was possible to form four different groups of interviewed landowners according to trust: networkers , opportunists , carefuls and selfemployed . Only in the group of opportunists the project created so much trust that a significant increase of interest to participate in the project was noticed. In all the other groups the project didn t create remarkable trust, so trust didn t have an effect on landowners decisions to participate. Other factors, like compensation and voluntariness were decisive for their interest to participate. From Sea to Forest project wasn t a network based on landowners co-operation, the communication was directly with the project worker. The effects on landowners income by signing a ten year ´Natural value trading´ -contract was analyzed by comparing the protection income with predicted forestry income in case that the protection contract wouldn t have been agreed on. For two landowners there was no suggested forestry work within ten years, so their protection income might be an additional income, if they decided to log their forests later. For three landowners delayed thinning of the sapling stand would cause income losses in the future, if they decided to move to active forestry after ten years of protection. For eight landowners the effect of protection is positive to income if they moved to active forestry after the ten years protection period. This occurred, because the tree stand is now mature for final felling on behalf of its age, but ten more years of growth increase the net present value. Longer term protection might diminish the net present value. The protection was profitable because hectare specific forestry income grew compared to forestry cutting plan income.

Natural regeneration and ecological succession in Pinus kesiya watershed plantations in northern Thailand : Implications on plantation management

Establishment of Pinus kesiya Roy. ex Gord. plantations in Thailand began in the 1960s by the Royal Forest Department. The aim was to reforest abandoned swidden areas and grasslands in order to reduce erosion and to produce timber and fuel wood. Today there are about 150, 000 ha of P. kesiya plantations in northern Thailand. Most of these plantations cannot be harvested due to a national logging ban. Previous studies have suggested that Pinus kesiya plantations posses a capability as a foster environment for native broadleaved tree species, but little is known about the extent of regeneration in these plantations. The general aim of the study was to clarify the extent of forest regeneration and interactions behind it in Pinus kesiya plantations of the Ping River basin, northern Thailand. Based on the results of this study and previous literature, forest management proposals were produced for the area studied. In four different pine plantation areas, a total of seven plantations were assessed using systematic data collection with clustered circular sample plots. Vegetation and environmental data were statistically analysed, so as to recognise the key factors affecting regeneration. Regeneration had occurred in all plantations studied. Regeneration of broadleaved trees was negatively affected by forest fire and canopy coverage. A high basal area of mature broadleaved trees affected the regeneration process positively. Forest fire disturbance had a strong effect also on plantation structure and species composition. Because of an unclear future forest management setting as regards forest laws in Thailand, a management system that enables various future utilisation possibilities and emphasises local participation is recommended for P. kesiya watershed platations of northern Thailand.

Expression Analysis of Host-Induced Genes and Proteins of Potato Pathogen Pectobacterium atrosepticum

Pectobacterium atrosepticum on Gram-negatiivinen bakteeri, joka aiheuttaa perunan tyvi- ja märkämätää. P. atrosepticum bakteerin optimilämpötila on melko alhainen ja se on yleinen lauhkeilla alueilla. Tyvimätä leviää pääasiassa siemenperunan välityksellä ja siksi se on ongelma erityisesti siemenperunan tuotannossa. P. atrosepticum kannan SCRI1043 genomi on julkaistu ja sitä tutkitaan malliorganismina märkä- ja tyvimädän taudinaiheuttamisen ymmärtämiseksi. Tämä opportunistinen taudinaiheuttaja voi elää isäntäkasvissa kuukausia piilevänä, aiheuttamatta näkyviä oireita. Suotuisissa olosuhteissa bakteerit alkavat jakautua ja tuottaa kasvin kudoksia hajottavia entsyymejä. Mädäntyvä kasvimassa tarjoaa ravinteita bakteerien kasvuun ja mahdollistaa isäntäkasvin asuttamisen. Soluseiniä hajottavien entsyymien merkitys taudinaiheuttamisessa on hyvin tunnettu, mutta oireettomasta jaksosta ja taudin alkuvaiheista tiedätään vain vähän. Bakteerin genomi sisältää monia toksiineja, adhesiineja, hemolysiineja ja muita proteiineja, joilla saattaa olla merkitys taudinaiheuttamisessa. Tässä työssä käytettiin proteomiikkaa ja mikrosiruanalysiä P. atrosepticum bakteerin erittyvien proteiinien ja geeniekspression tutkimiseen. Proteiinit, jotka eritetään ulos bakteerista, toimivat todennäköisesti taudinaiheuttamisessa, koska ne ovat suorassa kontaktissa isäntäkasvin kanssa. Analyysit suoritettiin olosuhteissa, jotka muistuttavat kasvin soluvälitilaa: matala pH, vähän ravinteita ja matala lämpötila. Isäntäkasvin läsnäolon vaikutusta proteiinien tuottoon ja geeniekspressioon tutkittiin lisäämällä perunauutetta kasvatusalustaan. Tutkimuksessa tunnistettiin P. atrosepticum bakteerin monia jo tunnettuja ja mahdollisesti taudinaiheuttamiseen liittyviä proteiineja. Perunauute lisäsi hiljattain tunnistetun, proteiinien eritysreittiä (tyyppi VI sekreetio, T6SS) koodaavien geenien ilmentymistä. Lisäksi bakteerin havaittiin erittävän useita T6SS:n liittyviä proteiineja kasvualustaan, johon oli lisätty perunauutetta. T6SS:n merkitys bakteereille on vielä epäselvä ja sen vaikutuksesta taudinaiheuttamiseen on julkaistu ristiriitaisia tuloksia. Märkä- ja tyvimädän ymmärtäminen molekulaarisella tasolla luo pohjan tautien kontrollointiin tähtäävään soveltavaan tutkimukseen. Tämä tutkimus lisää tietoa kasvi-patogeeni- interaktiosta ja sitä voidaan tulevaisuudessa käyttää hyväksi esimerkiksi diagnostiikassa, resistenttien perunalajikkeiden jalostuksessa tai viljely- ja varastointiolosuhteiden parantamisessa.

Genetic diversity of Atlantic salmon (Salmo salar) and European whitefish (Coregonus lavaretus) in the Baltic Sea

We described the patterns and extent of microsatellite DNA variation in historical and present-day Atlantic salmon (Salmo salar L.) stocks in the Baltic Sea and neighbouring areas, and in European whitefish (Coregonus lavaretus) ecotypes, populations and run-timing types in Finland. Moreover, the amount and pattern of genetic diversity in historical salmon populations before human impact were described, and the proportion of diversity maintained in the present hatchery stocks evaluated. Salmon populations in the Baltic Sea were, on average, significantly less variable than eastern Atlantic populations, and the diversity of landlocked populations (Lakes Vänern, Saimaa, Onega and Ladoga) was in turn significantly lower than that of anadromous salmon populations in the Baltic Sea populations. Within the Baltic Sea, the anadromous populations of Atlantic salmon formed three clear groups, corresponding to the northern (Gulf of Bothnia), eastern (Gulf of Finland and eastern Baltic Main Basin) and southern (western Baltic Main Basin) regions. Based on microsatellite data, three salmon population groups in the Baltic Sea were considered potentially different colonization lineages. In short- and long-term breeding programmes of Atlantic salmon, the average observed rate of loss of alleles was 4.9% and 2.0% per generation and the average rate of loss of heterozygosity was 1.4% and 1% per generation, respectively. When comparing the genetic parameters of stocks before and after hatchery breeding of several successive generations (Rivers Iijoki and Oulujoki), statistically significant changes in allele frequencies were common, while large wild stock in the Teno River has remained temporally very stable over 56 years. Despite the observed losses of genetic diversity in broodstock breeding, a large proportion of the genetic resources of the extirpated stocks are still conserved in the broodstocks. Genetic differentiation among European whitefish ecotypes was generally low, thus giving support to the hypothesis of one native European whitefish species in Fennoscandia. Among the ecotypes, the northern, large sparsely rakered, bottom-dwelling whitefish was the most unique. The known genetic differences in quantitative traits have thus either developed independently of potential phylogenetic lineages, or the lineages have mixed and the quantitative traits of the ecotypes, like gill-raker number, have later changed according to environment and selection pressures. Overall, genetic distances between the anadromous whitefish populations along the Finnish coast, especially in the Bothnian Bay area, were small. Wild whitefish populations studied had slightly higher allelic diversity than hatchery-reared populations in corresponding rivers.

Gympie messmate (plantations)

Gympie messmate is an important commercial wood products tree in Queensland that produces high quality, strong, extremely durable and attractive timber. Although only small volumes are harvested from native forests in Queensland, it has a well-established market, and is in demand nationally. Gympie messmate timber from native forest has been used for a range of construction, engineering, appearance products and round timbers.

Selenium and its effects on growth, yield and tuber quality in potato

Selenium (Se) has been demonstrated to be an essential trace element for maintenance of animal and human health. Although it has not been confirmed to be an essential micronutrient in higher plants, there is increasing evidence that Se functions as an antioxidant in plants. Selenium has been shown to exert a beneficial effect on crop growth and promotes stress tolerance at low concentrations. However, the specific physiological mechanisms that underlie the positive effects of Se in plants have not been clearly elucidated. The aims of this study were to determine the Se concentration in potato (Solanum tuberosum L.) and the effects of Se on the accumulation of carbohydrates, growth and yield in potato plants. An additional aim was to study the impact of Se on the total glycoalkaloid concentration in immature potato tubers. The distribution of Se in different biochemical Se fractions and the effect of storage on the Se concentration were studied in Se-enriched tubers. Furthermore, the effect of Se on raw darkening and translocation of Se from seed tubers to the next tuber generation was investigated. Due to the established anti-ageing properties of Se, it was of interest to study if Se affects physiological age and growth vigour of seed tubers. The Se concentrations in the upper leaves, roots, stolons and tubers of potato increased with increasing Se supplementation. The highest Se concentration was reached in young upper leaves, roots and stolons, indicating that added selenate was efficiently utilized and taken up at an early stage. During the growing period the Se concentration declined in the aerial parts, roots and stolons of potato plants whereas an intensive accumulation took place in immature and mature tubers. Selenium increased carbohydrate accumulation in the young upper leaves and in stolons, roots and tubers at maturity. This could not be explained by increased production of photoassimilates as net photosynthesis did not differ among Se treatments. The Se treated plants produced higher tuber yields than control plants, and at the highest Se concentration (0.3 mg kg-1) lower numbers of larger tubers were harvested. Increased yield of Se treated plants suggested that Se may enhance the allocation of photoassimilates for tuber growth, acting as a strong sink for both Se and for carbohydrates. Similarly as for other plant species, the positive impact of Se on the yield of potato plants could be related to its antioxidative effect in delaying senescence. The highest Se supplementation (0.9 mg kg-1) slightly decreased the glycoalkaloid concentration of immature tubers. However, at this level the Se concentration in tubers was about 20 µg g-1 DW. A 100 g consumption of potato would provide about 500 mg of Se, which exceeds the upper safe intake level of 400 µg per day for human dietary. The low Se applications (0.0035 and 0.1 mg kg-1) diminished and retarded the degree of raw darkening in tubers stored for one and eight months, which can be attributed to the antioxidative properties of Se. The storage for 1 to 12 months did not affect the Se concentrations of tubers. In the Se enriched tubers Se was allocated to the organic Se fraction, indicating that it was incorporated into organic compounds in tubers. Elevated Se concentration in the next-generation tubers produced by the Se enriched seed tubers indicated that Se could be translocated from the seed tubers to the progeny. In the seed tubers stored for 8 months, at high levels, Se had some positive effects on the growth vigour of sprouts, but Se had no consistent effect on the growth vigour of seed tubers of optimal physiological age. These results indicate that Se is a beneficial trace element in potato plants that exerts a positive effect on yield formation and improves the processing and storage quality of table potato tubers. These positive effects of Se are, however, dependent on the Se concentration and the age of the potato plant and tuber.