Hannu Hökkä, Ari Laurén, Leena Stenberg, Samuli Launiainen, Kersti Leppä, Mika Nieminen. (2021). Defining guidelines for ditch depth in drained Scots pine dominated peatland forests. Silva Fennica vol. 55 no. 3 article id 10494. https://doi.org/10.14214/sf.10494

Keywords: Pinus sylvestris; forest management; peatland; drainage; ditch network maintenance; process model; water table

Highlights: Process-based hydrological model was applied to drained peatland forests representing a wide range of conditions in Finland; Ditch depth keeping the median July–August water table below 0.35 m was defined; Ditch depth depended on climatic conditions, stand volume, peat properties, and ditch spacing; Shallower ditches than recommended in practice proved to be sufficient in most situations.

Abstract | Full text in HTML | Full text in PDF | Author Info

We used a process-based hydrological model SUSI to improve guidelines for ditch network maintenance (DNM) operations on drained peatland forests. SUSI takes daily weather data, ditch depth, strip width, peat properties, and forest stand characteristics as input and calculates daily water table depth (WTD) at different distances from ditch. The study focuses on Scots pine (Pinus sylvestris L.) dominated stands which are the most common subjects of DNM. Based on a literature survey, and consideration of the tradeoffs between forest growth and detrimental environmental impacts, long term median July–August WTD of 0.35 m was chosen as a target WTD. The results showed that ditch depths required to reach such WTD depends strongly on climatic locations, stand volume, ditch spacing, and peat thickness and type. In typical ditch cleaning areas in Finland with parallel ditches placed about 40 m apart and tree stand volumes exceeding 45 m³ ha^–1, 0.3–0.8 m deep ditches were generally sufficient to lower WTD to the targeted depth of 0.35 m. These are significantly shallower ditch depths than generally recommended in operational forestry. The main collector ditch should be naturally somewhat deeper to permit water outflow. Our study brings a firmer basis on environmentally sound forestry on drained peatlands.

Hökkä, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: hannu.hokka@luke.fi
Laurén, University of Eastern Finland, Faculty of Science and Forestry, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ari.lauren@uef.fi
Stenberg, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: leena.stenberg@luke.fi
Launiainen, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: samuli.launiainen@luke.fi
Leppä, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: kersti.leppa@luke.fi
Nieminen, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: mika.nieminen@luke.fi

Click this link to register to Silva Fennica.

If you are a registered user, log in to save your selected articles for later access.

Contents alert

Your selected articles
Send to email

Légaré S., Bergeron Y. et al. (2002) Influence of forest composition on understory co.. Silva Fennica vol. 36 no. 1 article id 567 (remove) | Edit comment

Heikinheimo O., (1938) Thinning of forest stands Silva Fennica vol. no. 46 article id 4533 (remove) | Edit comment

Meen E., Nielsen A. et al. (2012) Forest stand modelling as a tool to predict perf.. Silva Fennica vol. 46 no. 4 article id 906 (remove) | Edit comment

Appelroth E., (1942) Requisite for periodical inventories of private .. Acta Forestalia Fennica vol. 50 no. 12 article id 7365 (remove) | Edit comment

Kumpu A., Peltoniemi M. et al. (2025) Soil carbon and nitrogen in unmanaged forests in.. Silva Fennica vol. 59 no. 3 article id 24072 (remove) | Edit comment

Eriksson G., (1991) Challenges for forest geneticists. Silva Fennica vol. 25 no. 4 article id 5465 (remove) | Edit comment

Stolpe N., (1954) Observations on floating, its organizations and .. Acta Forestalia Fennica vol. 61 no. 5 article id 7417 (remove) | Edit comment

Pallasmaa J., (1987) The architecture of the forest Silva Fennica vol. 21 no. 4 article id 5335 (remove) | Edit comment

Sierla V. O., (1933) Timber transportation of the floating associatio.. Acta Forestalia Fennica vol. 39 no. 1 article id 7272 (remove) | Edit comment

Starr M., Westman C. J. (1978) Easily extractable nutrients in the surface peat.. Silva Fennica vol. 12 no. 2 article id 4990 (remove) | Edit comment

Follow @SilvaFennica