Maatalous- metsätieteellinen tiedekunta


Recent Submissions

  • Raisio, Juha (Helsingin yliopisto, 2016)
    The phenology and flowering of the pedunculate oak (Quercus robur L.) in Southern Finland was monitored during 1999-2006, in the Framnäs and Lenholm oak forests, which are mixed with hazels, birches, aspens, rowans, lindens, junipers, spruces, pines. Both stands are about 20 ha and located by the northern limit of natural distribution of oaks. The distance between the groves is about 60 km. A long-term pasture of about 150 years, on both islands has reduced the oak stands, however in recent decades selective cuttings have been made to help the oaks. In the south-western coastal areas degree days ranged from 1405,7 to 1737,7 d.d. in 1999-2006, indicating higher cumulating heat sums than on average over the normal period for the years 1981-2000. A total of 20 oaks × 3 branches /each tree sits in both stands, which equals 120 branches that were surveyed. The cork oak flowering model was modified to common oaks. Phases: 0-7 in male flowering were specified: from the dormant period (0) to swelling of the buds, from the onset of flowering to withering of the inflorescences (6). During the female flowering similar phases were found - from the rest period of apex buds (0) to the development of auxiliary buds on same year shoots. Further from the onset of first tiny female flowers to the withering of stigmas on the latest ones (6). The common oak flowering model was accurate enough and easy to apply in the survey. Male flowering began in 1999-2006 between 17th May and 6th June. Anthesis followed a few days later, when most of the staminate inflorescences had ripened. The catkins in the full length turned from green to bright yellow just before pollen release. Ripening was equal to phase 5 in the model of staminate flowering. Onset of the first female flowers began when the phase for stamens was about 3-4. Pollen receptivity of the first glossy reddish stigmas began when male flowering was about 5-5,5. The peak for female flowering took place a few days later than the anthesis, indicating protandry in common oak flowering. The period from pollination to fertilization is still a competition sequence for the pollen tubes. The stigmas, the developing female flower organs in gynoecium and the pollen tube cell tissue interact at the cell level. The self-incompatibility system acts on preventing selfing. Hence the loss of female flowers is huge, in some trees and in some years about 50% of the flowers fall down by the time of fertilization. Only 0-7,5% of the female flowers of the peak blossom period developed into acorns, which was less than in many other investigations. The suitable period for the common oak reproduction is very limited in the northernmost parts of its natural distribution. If the onset of the male flowering was delayed to early June, the number of female flowers was consequently low (years 1999, 2003, 2005). The detected linear regression is a topic for further studies. It remains unclear in this current scrutiny how the regulatory process acts on limiting the seed set and preventing extra ecological costs of any failing reproduction. In 2004-2006 a new potential pest, the black-dotted groundling, Stenolechia gemmella L. attacked the common oaks in many parts of Southern Finland. The moth larvae hollowed out new, same year shoots by length of few centimeters. Slightly afterwards shoots with their leaves and flowers turned brown. In July 2005 hundreds of withering shoots appeared in large oak crowns and of the monitored 1500 shoots in Framnäs 249 were infested by the moth larvae. Larvae and pupae are present in shoots in July, the adults emerge later in August or September.
  • Salo (os. Muurinen), Kirsti (Helsingin yliopisto, 2016)
    The history of Finnish school system has mutual interest with agricultural club established in USA in the beginning of 1900. Learning by doing was the motto for 4H-work and experiential learning was valued at school as well. The Evergreen Model of Environmental Education action plan describes the use of the outdoors as an expanded learning environment and to develop sustainability education at modern school. The model was initiated by a local 4H-association in collaboration with the local municipality and the schools. The intention according to the schools curricula and learning goals was to fulfill experiential learning out of doors and to realize a holistic vision of a sustainable learning environment. The development of the model started in 2003 with four pilot schools and by 2010 all 16 primary schools of the municipality were involved - from small village schools (32 96 students, grades 1 6) to large comprehensive schools (370 583 students, grades 1 9). Within seven years school gardens were built, active learning in nearby farms was conducted, and learning sessions were organized in the nearby forests and in special nature resorts. Research questions were: What were the reasons to start the collaboration to develop new methods and places for learning outdoors? How did the teachers experience garden activities and learning outdoors? What were hindrances and promoting factors for learning outdoors and gardening in school every day? The Evergreen Model of Environmental Education has shown positive results and could be at least partly applied in all schools. Action plans need to be developed depending on each school s own possibilities and surroundings. Schools possess limited resources and teachers need to feel starting a program and teaching outdoors is easy. Collaboration with specialists like farmers or gardeners is important while establishing outdoor education in addition to everyday school work. The size of a school was not a hindrance for outdoor learning but larger groups did require extra adults and more complex organizing efforts to have successful sessions.
  • Birge, Traci (Helsingin yliopisto, 2015)
    ABSTRACT Traditional rural biotopes are high nature value (HNV) farmlands that include grazed forests, woodlands, and semi-natural meadows formed through traditional agricultural practices. Agricultural intensification and associated changes in demographics and land use have resulted in a decline in traditional rural biotopes throughout Europe. Despite the downward trend, some farmers still do manage traditional rural biotopes. Literature in farmer behavior variously suggests that agency and structural factors determine farmer decision-making and conservation behavior, and that farmers engage in farming styles according to their own values. The objectives of this research are to 1) understand what motivates farmers and landowners to manage traditional rural biotopes, 2) test whether managers differ in motivation, knowledge or structural factors according to whether the traditional rural biotopes are used in the farming system or managed separately from it as conservation sites or landscape elements, and 3) explore conservation tools and frameworks that might be used to improve policy and agri-extension services for conservation and management of traditional rural biotopes. The purpose of this thesis is to provide support to traditional rural biotope conservation in agriculture by furthering knowledge about manager behavior and motivations and to add to the literature on farmer conservation behavior more broadly with management of traditional rural biotopes as a focus for understanding farmer conservation related decision-making. The thesis is based on a two-part study in which research was carried out via postal questionnaires and interviews with farmers in Raasepori Municipality, on the southern coast of Finland. In the first part of the study, I sent postal questionnaires to all farms in Raasepori to identify farms with managed traditional rural biotopes. I asked farmers about activities on their farms to determine whether farmers managing traditional rural biotopes differed from other farmers according to nature-based activities or entrepreneurship and to determine whether non-agricultural activities take place on traditional rural biotopes. I considered the results in the context of existing extension services and agri-environmental schemes and explored how holistic conservation tools and approaches, including adaptive management, and social-ecological systems could be used to improve services for farmers engaged in TRB management. In the second part of the study, I conducted in-depth semi-structured interviews with TRB managers to determine whether sites were managed as part of the farming system or apart from it, motivations for managing traditional rural biotopes, interest and knowledge of conservation of traditional rural biotopes and experiences with extension and inspection services. I tested whether managers who used traditional rural biotopes in their farming system differed from those who did not and examined farmer engagement in traditional rural biotope management according to two sociological theories used in studying farmer behavior: theory of planned behavior and farming styles. I also compare summary findings of management activities to an inventory carried out by Pykälä and Bonn (2000) and present evidence of non-agricultural direct-use benefits (direct use ecosystem services) provided by traditional rural biotopes. Results indicate that farmers mainly manage traditional rural biotopes for intrinsic values, especially of open landscape, and are less motivated by extrinsic values such as fodder production or collecting special agri-environmental subsidies. Farmers with managed traditional rural biotopes are more likely to engage in entrepreneurship activities that bring the public to their farms or result in branding of their products. Findings support the theory of planned behavior insofar as agency and personal values are important to decision-making. Managers of traditional rural biotopes do not form a distinct farming style, but a group of farmers was identified whose farming system is based on managing traditional rural biotopes and direct sale of the traditional rural biotope products, was identified as a distinct farming style. We called it TRB entrepreneurship . Implications of the findings for extension services and policy development are that farmers and landowners engaged in management should be viewed as partners in conservation and that adaptive management and understanding of manager heterogeneity should be used to develop and target extension services and conservation strategies.
  • Napola, Jaakko (Helsingin yliopisto, 2014)
    Tutkimuksessa selvitettiin kuusen itä- ja keskieurooppalaisten alkuperien menestymistä ja käyttömahdollisuuksia metsänviljelyssä Etelä-Suomessa. Tutkimuksen pääaineiston muodostivat 32 kuusen alkuperäkoetta, jotka Metsäntutkimuslaitos on perustanut vuosina 1959 87, sekä viisi muuta koeviljelystä, joissa on mukana ulkomaisia alkuperiä. Pääaineiston koeviljelykset sisältävät 149 ulkomaista alkuperää 16 maantieteelliseltä lähtöisyysalueelta. Alkuperät ryhmiteltiin alankoaineistoon (Baltia, Länsi-Venäjä, Valko-Venäjä ja Koillis-Puola) sekä vuoristoaineistoon (muiden muassa Böhmerwald, Sudeetit-Beskidit, Tatra ja Karpaatit). Kokeiden ikä oli mitattaessa 15 40 kasvukautta (keskimäärin 25 kasvukautta) istutuksesta. Eri koeviljelyksistä saadut tulokset muutettiin yhteismitallisiksi suhteuttamalla ne suomalaisten vertailuerien keskiarvoon. Tarkasteltuja kasvu- ja laatutunnuksia olivat pituus, rinnankorkeusläpimitta, rungon keskitilavuus ja puuston tilavuus sekä elävyys, poikaoksat ja korot. Korolla tarkoitetaan rungon kuoren halkeamaa tai muuta vaurioita, jossa on mustaa sienikasvustoa. Siemenen siirtomatkan eli leveys- ja pituusastesiirron sekä koepaikan lämpösumman vaikutusta elävyyteen, kasvuun ja rungon laatuun tutkittiin alankoaineistossa lineaarisen sekamallin avulla. Selitysasteet jäivät alhaisiksi. Korkein selitysaste oli poikaoksapuiden osuutta selittävällä mallilla, 38,7 prosenttia. Alankoaineistossa suhteellinen elävyys oli keskimäärin 97 prosenttia suomalaisten vertailuerien keskiarvosta (= 100) ja suhteellinen runkotilavuus 113 prosenttia. Koropuiden suhteellinen osuus oli alankoaineistossa 103 prosenttia ja poikaoksapuiden suhteellinen osuus 90 prosenttia. Käyttökelpoisin lähtöisyysalue metsänviljelyn kannalta on Viro. Virolaisia kuusialkuperiä voidaan viljellä Etelä-Suomessa alueilla, joiden lämpösumma on yli 1250 d.d. Länsi-Venäjän alkuperiä (Pihkova ja Novgorod) voidaan toistaiseksi suositella käytettäväksi vain etelärannikolla, koska sisämaassa ei ole näillä alkuperillä perustettuja koeviljelyksiä. Latvialaiset alkuperät menestyvät hyvin etelärannikolla ja paikoin sisämaassa, mutta niiden kasvatukseen liittyy kohonnut korovaurioiden riski. Valko-Venäjän ja Koillis-Puolan alkuperät ovat nopeakasvuisia, mutta korojen yleisyyden vuoksi niitä ei voida suositella käytettäväksi Suomessa. Keski-Euroopan vuoristoalkuperistä parhaiten menestyvät Böhmerwaldin, Tatran ja Karpaattien alkuperät. Näitäkään alkuperiä ei kuitenkaan voida suositella käytettäväksi Suomessa niiden kasvatukseen liittyvien riskien takia. Tutkimus vahvistaa oikeaksi nykyisen suosituksen, jonka mukaan Viron alkuperiä voidaan viljellä Suomessa Salpausselän eteläpuolella.
  • Uimonen, Sirpa (Helsingin yliopisto, 2011)
    The purpose of this study was to find out whether food-related lifestyle guides and explains product evaluations, specifically, consumer perceptions and choice evaluations of five different food product categories: lettuce, mincemeat, savoury sauce, goat cheese, and pudding. The opinions of consumers who shop in neighbourhood stores were considered most valuable. This study applies means-end chain (MEC) theory, according to which products are seen as means by which consumers attain meaningful goals. The food-related lifestyle (FRL) instrument was created to study lifestyles that reflect these goals. Further, this research has adopted the view that the FRL functions as a script which guides consumer behaviour. Two research methods were used in this study. The first was the laddering interview, the primary aim of which was to gather information for formulating the questionnaire of the main study. The survey consisted of two separate questionnaires. The first was the FRL questionnaire modified for this study. The aim of the other questionnaire was to determine the choice criteria for buying five different categories of food products. Before these analyses could be made, several data modifications were made following MEC analysis procedures. Beside forming FRL dimensions by counting sum-scores from the FRL statements, factor analysis was run in order to elicit latent factors underlying the dimensions. The lifestyle factors found were adventurous, conscientious, enthusiastic, snacking, moderate, and uninvolved lifestyles. The association analyses were done separately for each choice of product as well as for each attribute-consequence linkage with a non-parametric Mann-Whitney U test. The testing variables were FRL dimensions and the FRL lifestyle factors. In addition, the relation between the attribute-consequence linkages and the demographic variables were analysed. Results from this study showed that the choice of product is sequential, so that consumers first categorize products into groups based on specific criteria like health or convenience. It was attested that the food-related lifestyles function as a script in food choice and that the FRL instrument can be used to predict consumer buying behaviour. Certain lifestyles were associated with the choice of each product category. The actual product choice within a product category then appeared to be a different matter. In addition, this study proposes a modification to the FRL instrument. The positive towards advertising FRL dimension was modified to examine many kinds of information search including the internet, TV, magazines, and other people. This new dimension, which was designated as being open to additional information, proved to be very robust and reliable in finding differences in consumer choice behaviour. Active additional information search was linked to adventurous and snacking food-related lifestyles. The results of this study support the previous knowledge that consumers expect to get many benefits simultaneously when they buy food products. This study brought detailed information about the benefits sought, the combination of benefits differing between products and between respondents. Household economy, pleasure and quality were emphasized with the choice of lettuce. Quality was the most significant benefit in choosing mincemeat, but health related benefits were often evaluated as well. The dominant benefits linked to savoury sauce were household economic benefits, expected pleasurable experiences, and a lift in self-respect. The choice of goat cheese appeared not to be an economic decision, self-respect, pleasure, and quality being included in the choice criteria. In choosing pudding, the respondents considered the well-being of family members, and indulged their family members or themselves.
  • Heikkilä, Mari (Helsingin yliopisto, 2007)
    The chemical composition of breast milk has been studied in detail in the past decades. Hundreds of new antibacterial and antiviral components have been found. Several molecules have been found to promote the proper function of neonatal intestine. However, microbiological studies of breast milk have been, until recently, focused mainly on detecting harmful and pathogenic bacteria and viruses. Natural microbial diversity of human milk has not been widely studied before the work reported in this thesis. This is mainly because breast milk has traditionally been thought to be sterile - even if a certain amount of commensal bacteria have usually been detected in milk samples. The first part of this licentiate thesis contains a short literature review about the anatomy and physiology of breast feeding, human milk chemical and microbiological composition, mastitis, intestinal flora and bacteriocins. The second part reports on the experiments of the licentiate work, concentrating on the microbial diversity in the milk of healthy breast-feeding mothers, and the ability of these bacteria to produce antibacterial substances against pathogenic bacteria. The results indicate that human milk is a source of commensal bacteria for infant intestine. 509 random isolates from 40 breast milk samples were isolated and identified by 16S rRNA sequencing. Median bacterial count was about 600 colony forming units per milliliter. Over half of the isolates were staphylococci, and almost one third streptococci. The most common species were skin bacteria Staphylococcus epidermidis and oral bacteria Streptococcus salivarius and Streptococcus mitis. Lactic acid bacteria, identified as members of Lactobacillus-, Lactococcus- and Leuconostoc -genera, were found in five milk samples. Enterococci were found in three samples. A novel finding in this study is the capability of these commensal bacteria to inhibit the growth of pathogens. In 90 precent of the milk samples commensal bacteria inhibiting the growth of Staphylococcus aureus were found. In 40 precent of samples the colonies could block the growth completely. One fifth of the isolated Staph. epidermidis strains, half of Str. salivarius strains, and all lactic acid bacteria and enterococci could inhibit or block the growth of Staph. aureus. In further study also Listeria innocua- and Micrococcus luteus active isolates were found in 33 and 11 precent of milk samples (out of 140). Furthermore, two Lactococcus lactis isolates from the breast milk were shown to produce bacteriocin nisin, which is an antimicrobial molecule used as a food preservative. The importance of these human milk commensal bacteria in the development of newborn intestinal flora and immune system, as well as in preventing maternal breast infections, should be further explored.
  • Tall, Anna (2007)
    Julkaisuja / Helsingin yliopisto, soveltavan biologian laitos
  • Harmanen, Heikki (2007)
    Julkaisuja / Helsingin yliopisto, soveltavan biologian laitos