Suo - Mires and peat vol. 45 no. 1 | 1994
Kaksiosaisten turvepohjaisten kasvualustojen vaikutus männyn paakkutaimien kasvuun.
English title: Effect of peat-based two-component growth media on the growth of containerized scots pine seedlings.
Tiivistelmä |
Näytä lisätiedot
|
Artikkeli PDF-muodossa |
Tekijä
One-year-old containerized scots pine seedlings (Pinus sylvestris L.) were grown in two-component growth media mixtures containing 75% (by volume) light, low humified Sphagnum peat and under an irrigation regime where the seedlings were abundantly reirrigated after -10 to -15 kPa matric potential was achieved in the growth media. The greatest seedling growth was in pure peat and in peat to which coarse perlite had been added. The poorest growth was in mixtures of peat and hydrogel and of peat and water repellent rockwool. Intermediate growth was found in peat to which fine perlite or water absorbent rockwool had been added. During drying in the range -2 to -90 kPa matric potential of the growth medium, the decrease in the net photosynthesis of seedlings at the bud formation phase was linear when aeration was not a restricting factor. During drying, the net photosynthesis was relatively large and was of a similar magnitude in pure peat and in peat to which coarse or fine perlite had been added. Significantly smaller net photosynthesis was observed in peat to which water repellent rockwool or water absorbent rockwool or hydrogel had been added. During drying under wet conditions (-1 to -4 kPa matric potential) when limited aeration was a restricting factor, the net photosynthesis increased linearly. Due to better aeration, the, net photosynthesis was higher in the mixture of peat and coarse perlite than in pure peat.
Keywords: aeration, nutrients, photosynthesis, physical properties of soil, substrate, water retention
J. Heiskanen, The Finnish Forest Research lnstitute, Suonenjoki Research Station, FIN-77600 Suonenjoki, Finland
-
Heiskanen,
Sähköposti:
ei.tietoa@nn.oo
Kuusamon suokasvillisuus ja ojitustilanne.
English title: Mire site types and peatland drainage in Kuusamo, northern Finland.
Tiivistelmä |
Näytä lisätiedot
|
Artikkeli PDF-muodossa |
Tekijä
The percentage distribution of mire site types on 49 random sample plots (1/4 km2) was studied in 1989. The line transect method was used, the total mire transect line on the sample plots being 100,6 km. The eight most common mire site types include different pine bog types (hummock level bogs/pine mires) and fens. Both poor fens and rich fens are more common in Kuusamo than in the Pohjanmaa aapa mires (southern aapa mires), the former ones taking 29% and the latter ones 8% of all mires. The percentage of spruce mires (6% ) is no more than a half of their percentage in the Pohjanmaa aapa mires. 32% of the peatlands studied were under the influence of drainage, mainly with open ditch networks for forestry. 16% of those were classified as recently drained, 73% as transitional, 5% as drained peatland forests and 6% as being influenced by drainage in the vicinity. Open fens and thick peated mire types have been drained to a lesser extent than forested mires and sites with mire margin effect. However, as only few mire site types are suitable for forestry in northern Finland, the risk of unprofitable drainage is high. Mire site types considered unsuitable for forestry even in the more favourable conditions of southern Finland take about 35% of the drained mires.
Keywords: Aapa mire area, draining for forestry, field survey, mire vegetation, Peräpohjola
-
Paasovaara,
Keskuskoulu B 7, FIN-86710 Kärsämäki, Finland
Sähköposti:
ei.tietoa@nn.oo
Click this link to register to Suo - Mires and peat.
Jos olet rekisteröitynyt käyttäjä, kirjaudu sisään tallentaaksesi valitsemasi artikkelit myöhempää käyttöä varten.
Valitsemasi artikkelit
Suo - Mires & Peat
