Browsing by Subject "turvemaat"

Sort by: Order: Results:

Now showing items 1-20 of 64
  • Westman, Carl Johan; Starr, Michael; Laine, Jukka (Suomen metsätieteellinen seura, 1985)
  • Grammatikopoulou, Ioanna; Artell, Janne; Hjerppe, Turo; Pouta, Eija (Springer Link, 2020)
    Environmental and Resource Economics 77, 615–639
    Studies on the public’s implicit discount rate in the willingness to pay for environmental amenities have mostly employed contingent valuation surveys. We investigate respondents’ time preferences using choice experiments with four payment schedules in a split-sample design in the context of mire conservation. We first examine preference and taste heterogeneity among respondents, finding them to a large extent independent of payment schedules. Next we use an endogenous approach to jointly estimate the implicit discount rates and preferences using choice experiments data. We explore exponential and hyperbolic discounting model specifications. We find insensitivity to the length of the payment period and support for hyperbolic discounting. Furthermore, we provide policy relevant valuation results concerning mire conservation.
  • Erjala, Pentti; Saramäki, Jussi (Suomen metsätieteellinen seura, 1972)
  • Finér, Leena (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
    Biomass, biomass increment and nutrient cycling were studied in (1) a Scots pine (Pinus sylvestris) stand, (2) a Norway spruce (Picea abies) stand and (3) a mixed birch (Betula pubescens)/pine stand on a drained mire at Ilomantsi, eastern Finland in 1979-85. In addition, the effect of NPK and micronutrient fertilizer treatment was studied. Above-ground and root measurements were taken. These data formed the basis of stand biomass and nutrient cycle simulations of fertilized and unfertilized stands. The increases in biomass were greater in (1) and (2) in the fertilized simulation than in the unfertilized one. For (3), the effect of fertilization on biomass increment was small. In six years only part of the applied fertilizer had been fixed in the biomass of the model stands and proportionally less micronutrients than macronutrients. The potassium stores were small compared to the nutrient amounts fixed by the stands. This supports the notion that there is a shortage of potassium on deep-peat soils.
  • Rajakallio, Maria; Jyväsjärvi, Jussi; Muotka, Timo; Aroviita, Jukka (Blackwell, 2021)
    Journal of Applied Ecology 58: 7, 1523-1532
    1. Growing bioeconomy is increasing the pressure to clear-cut drained peatland forests. Yet, the cumulative effects of peatland drainage and clear-cutting on the biodiversity of recipient freshwater ecosystems are largely unknown. 2. We studied the isolated and combined effects of peatland drainage and clear-cutting on stream macroinvertebrate communities. We further explored whether the impact of these forestry-driven catchment alterations to benthic invertebrates is related to stream size. We quantified the impact on invertebrate biodiversity by comparing communities in forestry-impacted streams to expected communities modelled with a multi-taxon niche model. 3. The impact of clear-cutting of drained peatland forests exceeded the sum of the independent effects of drainage and clear-cutting, indicating a synergistic interaction between the two disturbances in small streams. Peatland drainage reduced benthic biodiversity in both small and large streams, whereas clear-cutting did the same only in small streams. Small headwater streams were more sensitive to forestry impacts than the larger downstream sites. 4. We found 11 taxa (out of 25 modelled) to respond to forestry disturbances. These taxa were mainly different from those previously reported as sensitive to forestry-driven alterations, indicating the context dependence of taxonomic responses to forestry. In contrast, most of the functional traits previously identified as responsive to agricultural sedimentation also responded to forestry pressures. In particular, taxa that live temporarily in hyporheic habitats, move by crawling, disperse actively in water, live longer than 1 year, use eggs as resistance form and obtain their food by scraping became less abundant than expected, particularly in streams impacted by both drainage and clear-cutting. 5. Synthesis and applications. Drained peatland forests in boreal areas are reaching maturity and will soon be harvested. Clear-cutting of these forests incurs multiple environmental hazards but previous studies have focused on terrestrial ecosystems. Our results show that the combined impacts of peatland drainage and clear-cutting may extend across ecosystem boundaries and cause significant biodiversity loss in recipient freshwater ecosystems. This information supports a paradigm shift in boreal forest management, whereby continuous-cover forestry based on partial harvest may provide the most sustainable approach to peatland forestry.
  • Bhattacharjee, Joy; Marttila, Hannu; Launiainen, Samuli; Lepistö, Ahti; Kløve, Bjørn (Elsevier, 2021)
    Science of The Total Environment 779 (2021), 146419
    Maintaining and improving surface water quality requires knowledge of nutrient and sediment loads due to past and future land-use practices, but historical data on land cover and its changes are often lacking. In this study, we tested whether land-use-specific export coefficients can be used together with satellite images (Landsat) and/or regional land-use statistics to estimate riverine nutrient loads and concentrations of total nitrogen (TN), total phosphorus (TP), and suspended solids (SS). The study area, Simojoki (3160 km2) in northern Finland, has been intensively drained for peatland forestry since the 1960s. We used different approaches at multiple sub-catchment scales to simulate TN, TP, and SS export in the Simojoki catchment. The uncertainty in estimates based on specific export coefficients was quantified based on historical land-use changes (derived from Landsat data), and an uncertainty boundary was established for each land-use. The uncertainty boundary captured at least 60% of measured values of TN, TP, and SS loads or concentrations. However, the uncertainty in estimates compared with measured values ranged from 7% to 20% for TN, 0% to 18% for TP, and 13% to 43% for SS for different catchments. Some discrepancy between predicted and measured loads and concentrations was expected, as the method did not account for inter-annual variability in hydrological conditions or river processes. However, combining historical land-use change estimates with simple export coefficients can be a practical approach for evaluating the influence on water quality of historical land-use changes such as peatland drainage for forest establishment.
  • Starr, Michael; Westman, Carl Johan (Suomen metsätieteellinen seura, 1978)
  • Silvola, Jouko; Välijoki, Jukka; Aaltonen, Heikki (Suomen metsätieteellinen seura, 1985)
    At sites in SE Finland, hourly respiration varied mainly in the range 100-500 mg CO2/msuperscript 2 with changes following those in soil surface temp. with a time lag of 3 h. After groundwater table was reduced by about 0.5 m, respiration increased 2.5-fold (resulting in a rate of peat decomposition considerably in excess of the rate of production of new organic matter in the peat). Application of fast-dissolving PK or urea rapidly increased soil respiration at the site poorest in nutrients. Ash gave the greatest steady increase. At sites rich in nutrients, fertilizer treatment reduced soil respiration for 1-2 yr. Treatment with micronutrients caused an intial reduction in respiration followed by a pronounced increase.
  • Paavilainen, Eero (Suomen metsätieteellinen seura, 1990)
  • Mannerkoski, Hannu (Suomen metsätieteellinen seura, 1973)
  • Westman, Carl Johan (Suomen metsätieteellinen seura, 1981)
  • Heikurainen, Leo; Päivänen, Juhani; Sarasto, Juhani (Suomen metsätieteellinen seura, 1964)
  • Heikurainen, Leo (Suomen metsätieteellinen seura, 1967)
  • Tertsunen, Jermi; Martinmäki, Kati; Heikkinen, Kaisa; Marttila, Hannu; Saukkoriipi, Jaakko; Tammela, Simo; Saarinen, Tuomas; Tolkkinen, Mikko; Hyvärinen, Marja; Ihme, Raimo; Yrjänä, Timo; Klöve, Björn (Suomen ympäristökeskus, 2012)
    Suomen ympäristö 37/2012
    Sanginjoki, Oulujoen alin sivujoki, on Oulun seudun tärkeimpiä virkistysalueita ja Merikosken kalatietä lähin potentiaalinen vaelluskalojen nousualue. Joen ajoittainen happamuus kuitenkin heikentää Sanginjoen virkistyskäytöllistä ja ekologista arvoa. Kaupunki ja vesi – Sanginjoen virkistyskäyttöarvon parantaminen ja ekologinen kunnostus (2008-2011) -hankkeessa selvitettiin Sanginjoen happamuuden alkuperää, seurattiin laajasti eri alueilta jokeen laskevien valumavesien pH:n muutoksia sekä testattiin menetelmiä happamien huuhtoumien ennaltaehkäisyyn ja neutralointiin. Tulosten perusteella laadittiin toimenpidesuunnitelma happamuuden ehkäisemiseksi sekä happamuuden aiheuttamien haittojen lieventämiseksi. Julkaisussa on myös esitetty tietoa Sanginjoen ja sen valuma-alueen ominaisuuksista, joen ekologisesta tilasta, vedenlaadun kehityksestä sekä happamuuden ehkäisemiseen soveltuvista menetelmistä. Tulosten perusteella Sanginjoen veden happamuus usein voimistuu virtaamien kasvaessa. Etenkin kesä- ja syyssateiden yhteydessä havaittiin alhaisia pH-lukemia, joihin vaikuttivat maaperä, kasvillisuus ja maankäyttö. Hapan huuhtouma on pääosin peräisin turvepitoisten maiden orgaanisesta huuhtoumasta, mutta paikallisesti vedenlaatuun voivat vaikuttaa alueella esiintyvät happamat sulfaattimaat ja mustaliuskealueet. Sanginjoen vesi on ollut myös luontaisesti hapanta lähinnä suo- ja turvemaiden happamien valumavesien johdosta, mutta happamuus on todennäköisesti lisääntynyt ihmistoiminnan vaikutuksesta. Sanginjoen valuma-alueella testattujen vesiensuojelu- ja kunnostusmenetelmien vaikutukset happamien valumavesien neutraloinnissa vaihtelivat, mutta osa menetelmistä osoittautui käyttökelpoiseksi ja niitä voidaan suositella käytettävän jatkossa niin Sanginjoella kuin vastaavilla happamuudesta kärsivillä kohteilla. Menetelmien kehittämistä ja erityisesti vaikutusten seurantaa tulee kuitenkin edelleen jatkaa. Hankkeessa testatut menetelmät ovat keinoja ihmistoiminnasta aiheutuvan happamuuden lisääntymisen torjunnassa. Parhaiten Sanginjoen ja muiden happamuudesta kärsivien vesistöjen hapanta kuormitusta ehkäistään huomioimalla maankäytössä happamuuden kannalta kriittisten turve- ja sulfidipitoisten alueiden ominaisuudet ja sijoittuminen jo ennen maankäytön toimenpiteitä ja kuormituksen syntymistä.
  • Päivänen, Juhani (Suomen metsätieteellinen seura, 1973)