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Hirvikannan seuranta Suomessa : Menetelmä ja kannan kehitys tällä vuosituhannella
Get PDFSuomen hirvikannan maa- ja metsätalousministeriön vuonna 2014 vahvistamaan hoitosuunnitelmaan perustuva tavoitteellinen hirvikannan hoito tarvitsee luotettavia työkaluja, joiden avulla voidaan arvioida hirvitalousalueille asetettujen hirvikantaa koskevien tavoitteiden toteutumista ja suunnitella tavoitteisiin johtavaa kannan verotusta. Suomen hirvikannan kokoa ja rakennetta arvioidaan Bayes-tilastotieteeseen pohjautuvan kannanarviomallin avulla. Mallilla tuotetaan hirvitalousalueittain hirvikannan koon ja rakenteen arvioiden aikasarja todennäköisyysväleineen vuodesta 2000 nykyhetkeen. Mallin ytimenä on populaatiomalli, jossa mallinnetaan erikseen aikuisten urosten ja naaraiden sekä uros- ja naarasvasojen lukumääriä vuoden kierrossa ja vuodesta toiseen. Populaatiomallin tuottamaa kannan kehitystä ehdollistaa siihen vaikuttavista prosesseista (lisääntyminen ja kuolleisuus) ja kannan koosta saatavissa oleva tieto. Lisääntymistä koskevaa tietoa saadaan metsästäjien hirvijahdin aikana tekemistä hirvihavainnoista ja kuolleisuutta koskevaa tietoa hirvikolareiden lukumäärästä, suurpetokantojen koon arviosta lasketusta poistumasta sekä mm. kirjallisuuteen perustuvasta arviosta muusta taustakuolleisuudesta. Kannan koosta ja sen kehityksestä saadaan tietoa jahdinaikaisten päivittäisten hirvihavaintojen lukumäärästä, metsästäjien ilmoittaman jahdin jälkeen jäävän hirvikannan koon arviosta, mahdollisista maa- ja lentolaskennoista sekä hirvikolareista. Mallinnus tehdään siten, että populaatiomalliin liitetään nämä tiedot uskottavuusfunktioiden kautta. Mallinnus toteutetaan R-ohjelmointiympäristössä käyttäen mallin parametrien estimoinnissa JAGS-ohjelmistoa.
Mallilla saatujen tulosten perusteella hirvikanta on pienentynyt Suomessa tällä vuosituhannella noin 50 %. Vuosituhannen alussa suuri hirvikanta aiheutti paljon hirvikolareita ja vahinkoja metsätaloudessa ja hirvisaaliita kasvatettiin kannan pienentämiseksi. Myöhemmin vuoden 2015 jälkeen hirvitalousalueittain asetetut hirvikannan tiheyden ja rakenteen tavoitteet ovat ohjanneet hirvikannan säätelyä. Syksyn 2022 jahdin jälkeen 45,8 prosentilla hirvitalousalueista hirvitiheysarvio oli asetetussa tavoitehaarukassa. Hirvikannan lehmiä / sonni – suhde on pienentynyt hirvikannan voimakkaan pienentämisen yhteydessä joillain alueilla korkeiksikin kasvaneista lukemista melko lähelle tavoitteena olevaa tasoa 1,5. Aikuisia naaraita kohden laskettujen vasatuottojen trendinomainen pienentyminen tällä vuosituhannella on huolestuttavaa ja edellyttää ilmiön syiden selvittämistä.202
Farmers’ futures: an application of the Delphi method in the context of Finnish agriculture
Get PDFIn Finland, agriculture is practiced in variable growing conditions that are further challenged by climate change and under external pressure caused by international competition, changing consumer preferences and demands, and the renewal of the European Union Common Agriculture Policy and Paris Agreement climate targets. Futures studies in agriculture have focused on scenario building with expert panels, though usually without farmers’ involvement. This study focuses on farmers’ views of shaping the future of Finnish agriculture. It builds on the disaggregative Delphi method and combines interviews and a representative survey of Finnish farmers. The study is based on a bottom-up process in which a farmer panel of 20 farms defined their views of the future in a semi-structured thematic interview. The views were turned into statements in a structured survey sent to the second panel, which comprised all Finnish farmers who had received agricultural subsidies in 2016, with 4401 respondents. The results were analyzed using quantitative factor analysis, which produced five future images for Finnish agriculture. The images were shown to the original farmer panel for reflection. They considered the probability of each future image and their own role in it. Technology solves as a future image was most favored by farmers, followed by Ecological and specializing small-scale production image. Business-as-usual was the least likely future images according to the interviewed farmers. This paper describes the process and discusses both methodological benefits and pitfalls, as well as farmers’ future views of the forthcoming decades.202
Lannan ja oljen yhteiskäsittely biokaasuprosessissa - käsittelyn vaikutus mädätteen hiilen pysyvyyteen maaperässä
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Predicting the future of our oceans : Evaluating genomic forecasting approaches in marine species
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Comparing structural soil properties of boreal clay fields under contrasting soil management
Get PDFSoil management significantly affects soil structure. Tillage and grassland renovation may have destructive influences, while conversion of arable land to grassland can improve pore structure and related soil functions. In crop rotations including perennial grasses, soil structure is affected by these counteracting processes. This work aimed to quantify the impacts of different soil management practices on the structure of boreal clay soils. We studied intact topsoil samples taken from two locations by X-ray computed microtomography, image-based flow simulations and water retention measurements. At both locations, adjacent field areas with two contrasting soil management histories were compared. Both locations had at least a 30-year-old grassland site, which was compared to arable soils either under no-till management with annual crop rotation or conventional tillage with crop rotation including perennial grasses. Both imaging and water retention measurements showed significant differences in the soil macropore structure between the long-term grassland and arable no-till soil such that macroporosity and hydraulic conductivity of the long-term grassland were higher than those of soil under agricultural production. On the contrary, at the second study location, differences between long-term grassland and cultivated fields were minor and the long-term grassland exhibited lower macroporosity. Our results confirm that soil management affects the macropore structure of boreal clay soil and that no-till annual cropping and periodically tilled crop rotation including perennial phases exert different effects on the soil structure as compared with long-term grassland.202
Determinants of the economy in multistrata agroforestry in Ethiopia
Get PDFAgroforestry represents a potentially multi-beneficial approach to land management as it may enhance a farming household’s income and income stability simultaneously with nutrition security and climate change mitigation. However, our comprehension of the specific characteristics within agroforestry systems that bolster economic productivity remains limited, exacerbating the challenges of land management for smallholder livelihoods. This complexity is compounded by the potential influence of carbon revenue, adding an additional layer of intricacy to the equation. This paper aimed to identify the key economic determinants of multistrata agroforestry in sub-Saharan Africa with and without potential carbon revenue. A quantitative survey of 135 farmers was performed regarding their multistrata agroforestry systems with contrasting histories in three regions of Ethiopia. The carbon sequestration rate and carbon stocks in agroforestry were assessed on one-fifth (27) of the farms. The relative importance of hypothetical determinants of agroforestry systems’ economic performance was modeled using descriptive statistics and generalized linear models. Farm size and fertilizer usage were the primary drivers of the farm economy, but farm net income was also highly influenced by the richness and diversity of the income sources. In addition, tree diversity had a positive impact on the net income, whereas the proportion of legume trees and trees with a large diameter correlated negatively with the income. Potential carbon revenue at prices of US100 tCO2−1 increased income for multistrata agroforestry farms without significantly changing the magnitude of the identified key determinants. This suggests that the most economically viable agroforestry systems inherently possess a strong capacity for carbon sequestration, effectively serving as carbon sinks. Consequently, carbon revenue serves as a compelling financial incentive for the adoption of these agroforestry systems. Ultimately, this research underscores the pivotal role of biological and product diversity in shaping economic productivity within multistrata agroforestry systems. Moreover, it highlights the accessibility of diversity management for smallholder farmers, even under conditions of resource constraints.202
Lesson from the emergence, spread and decline of Dickeya solani, the virulent potato blackleg and soft rot bacterial pathogen in Finland
Get PDFThe threat of emerging plant diseases has become more frequent as global warming and international trade are increasing. Blackleg and soft rot of potatoes caused by the group of bacteria in the family Pectobacteriaceae and the genera Dickeya and Pectobacterium are important diseases causing economic losses globally. In the European Union, they are regulated non-quarantine pests. Five species are commonly known to cause blackleg symptoms on potatoes indistinguishable from each other. For decades, P. atrosepticum has been the classic seed potato bacterial pathogen in cool temperate climates of Europe and North America, causing blackleg disease. However, recently several new species, unknown in Northern Europe, have emerged as virulent pathogens. One of these species is D. solani. In Finland, D. solani was first found in 2004 and has been the cause of major outbreaks of blackleg in Finland for more than a decade. Currently, its incidence has declined significantly because of a stringent, concerted engagement strategy adopted to combat the pathogen that is described in detail in this article. This strategy implemented in Finland could serve as a model system to combat other emerging and re-emerging species of Dickeya and Pectobacterium and serve as useful support information for the formulation of a policy framework for the management of emerging plant health risks.202
Site index and stand characteristic models for silver birch plantations in southern and central Finland
Get PDFGreat interests in silver birch (Betula pendula) forests have increased in an attempt to handle biodiversity and resilient forest management with more broad-leaved forests. However, up-to-date silver birch growth and yield models are still needed to predict the stand development in the future and support operational forest management and planning. The objectives of this study were to develop site index and stand characteristic models for silver birch plantations. Data for modelling were from the thinning and spacing experiments and tree breeding trials on silver birch plantations in southern and central Finland. The dominant height and site index (SI) models were fitted using the nonlinear mixed effect regression approach based on the Chapman-Richards function with the genetic effect from improved seedlings. The modelling result indicated a logical growth performance over age and higher dominant height with genetically improved seedlings. The stand characteristic models for unimproved seedlings were developed using multivariate mixed-effects modelling approach. The targeted, response variables were the basal area-weighted mean height (HW, m), the basal area-weighted mean diameter (DW, cm) and stand basal area (G, m2 ha−1) of silver birch. Stand biological age (AGE, year), SI estimated based on the model of the current study with the base age of 50 years, and the number of silver birch trees (N, trees ha−1) were all commonly applied as highly significant predictor variables for all of HW, DW, and G models. In addition to these predictors, thinning variables, comprised of the time since last thinning in year and the thinning intensity based on G, were highly significant in the DW and G models with logical behavior. Recent thinning affected negatively at first because trees in thinned stands were slimmer than those in unthinned stands that have grown from the early stage at the same level of N with thinned stands. After 13 years since last thinning, the effect turned positive indicating that the increments were expedited with thinning. Lastly, site type classified as either former agricultural land or forest site was included in the DW and G models. Consequently, all the models developed in this study were evaluated as practicable with easy-to-use predictors and desirable accuracy.202
Ekotoksisuus elinkaariarvioinnissa : Elintarvikkeiden ja ruokajärjestelmän elinkaariarviointimetodologian kehittäminen ja harmonisointi -hanke
Get PDFEkotoksisuus kuvaa myrkyllisten aineiden vaikutuksia ympäristöön. Sitä arvioitaessa tarkastellaan aineiden kulkeutumista ja jäämiä ympäristössä (eliöt, maaperä, vesistö, ilma) ja niiden vaikutuksia sen eliöstöön. Elinkaariarviointi (LCA, Life Cycle Assessment) -menetelmällä mitataan ja tunnistetaan tuotteen tai palvelun elinkaarenaikaiset ympäristövaikutukset. Elinkaariarvioinnin ekotoksinen vaikutusluokka kuvaa tuotteiden ekotoksisia vaikutuksia, jotka aiheutuvat ympäristölle tuoteketjuissa käytetyistä kemikaaleista. Se mahdollistaa eri tuotteiden välisen vertailun ja myös kemikaalien vaikutusten vertailun suhteessa toisiinsa. Menetelmä yhdistää elinkaariarvioinnin (LCA) ja riskiarvioinnin. Tunnistamalla ja tiedostamalla kemikaalien vaikutuksia tuoteketjuissa voidaan pyrkiä vähentämään aineiden haitallisia vaikutuksia vähentämällä kemikaalien määrää tai vaihtamalla niitä vähemmän haitallisiin vaihtoehtoihin.
Tämä kirjallisuuskatsaus sisältää perustietoa ekotoksisesta ympäristövaikutusluokasta elinkaariarvioinnissa (LCA, Life Cycle Assessment). Kemikaaleista esimerkkeinä käytetään kasvinsuojeluaineita. Katsauksessa esitetään myös joitakin ekotoksisten vaikutusarvioinnin menetelmiä.202