Calculations were made for five ten years periods (though each management schedule was continued to the final felling or at the maximum up to the 150 years). The results are reported only for the first 30 year period and the years beyond that era are for sustainability reasons.
In MELA2016 - program (Hirvelä ym. 2017) treewise basal-area growth models are calibrated using growth measurement data from 8th NFI. For calibration, growth measurements were adjusted with growth indices to the average level of diameter increment for years 1965 - 1994 (Henttonen 2000, Hynynen et al. 2002). For calculations presented here, tree basal-area growth models for forest land were calibrated using growth measurement data from 11th NFI. For calibration, growth measurements were adjusted with growth indices to the average level of diameter increment for years 1994 - 2013. (Korhonen et al. 2007). The calibration was done with sample trees from NFI measured in years 2009-2013. Sample trees in a sample plot were accepted to calibration data if the sample plot was at forest land, the whole sample plot was in a single stand and no cuttings were recorded for the 10 year period before the measurement year. The estimate of volume growth obtained using calibrated basal area growth was still adjusted up to the NFI12 measured growth level.
The estimate of volume growth obtained using calibrated basal area growth was still adjusted using the realized average 30 year weather data for 1970–1999 (1999 is the middle year of the calibration period of 1984-2013) and 1988–2017 and transformation functions of Matala et al (2005). Those functions were used in order to predict the change in the growth as a function of the increases in mean temperature and CO2 concentration between the long term averages of 1999 and 2017 which were in the Southern Finland 0,89 °C and 41,2 ppm and in the Northern Finland 0,996 °C and 41,2 ppm. By this way, the estimate of volume growth for 2016–2025 with during the years 2016–2018 realized removals was 105,5 mill. m3/year while the NFI12 measured growth (middle year 2013) was 107,8 mill. m3/year.
Average basal area growth of sample trees
| Tree species | Sample trees n |
Basal area growth of sample trees, cm2/5 years |
|||
| NFI11, corrected with indices | MELA2016 | ||||
| No calibration | Calibrated | ||||
| Mineral soils | |||||
| Pine | 17592 | 42,1 | 41,6 | 43,9 | |
| Spruce | 11958 | 50,7 | 57,2 | 52,4 | |
| Hardwoods | 8049 | 35,9 | 30,1 | 34,0 | |
| Total | 37599 | 43,5 | 44,1 | 44,5 | |
| Unditched organic soils | |||||
| Pine | 785 | 24,8 | 8,5 | 18,1 | |
| Spruce | 557 | 28,0 | 17,2 | 23,3 | |
| Hardwoods | 586 | 19,3 | 9,4 | 13,3 | |
| Total | 1928 | 24,1 | 11,3 | 18,1 | |
| Ditched organic soils | |||||
| Pine | 5497 | 34,3 | 25,5 | 35,3 | |
| Spruce | 2213 | 45,9 | 38,1 | 41,7 | |
| Hardwoods | 2933 | 26,4 | 22,1 | 23,8 | |
| Total | 10643 | 34,5 | 27,2 | 33,4 | |
Logging residue (waste wood) is part of cutting drain that is felled but not hauled from the forest and it is defined as non-commercial fraction of felled stems, i.e. part of a stem that does not fulfill the minimum Finnish timber assortment standards by size and quality of the industrial wood.
In MELA, stem volume (incl. bark) of an individual tree and the volumes of saw log, pulpwood and waste wood (non-commercial fraction of a stem) as solid cubic meter are obtained applying taper curve models and volume functions of Laasasenaho (1982). The saw log volume obtained by the models of Laasasenaho is still reduced by built-in log-volume reduction model of Mehtätalo (2002). This reduction is added to the pulpwood.
However, in practice the amount of waste wood in loggings can differ from the model estimated due to the stump height, used minimum measures, defected stems or due to the commercial timber not hauled. To reduce this gap the model estimations of waste wood of MELA in each logging was calibrated with NFI12 measurements (table below), such that the percentage in each pure industrial roundwood felling MELA event matched up with NFI12 figures. The reduction, when necessary, was made from pulpwood.
Relative fractions of waste wood in NFI12 by tree species, felling types and by regions, % of cutting drain:
| Final fellings | Other fellings | ||
| South Finland | Pine | 1,6 | 5,1 |
| Spruce | 2,1 | 7,6 | |
| Deciduous | 8,8 | 16,5 | |
| North Finland | Pine | 3,1 | 6,8 |
| Spruce | 5,3 | 13,9 | |
| Deciduous | 15,7 | 20,2 | |
The example of the impact of used calibration in MELA cutting removal calculation based on the amount realized removals in 2016-2018:
Cutting residue (waste wood) in industrial roundwood loggings, mill. m3/y
| 2016-2025 | 2026-2035 | 2036-2045 | |
| MELA | 1,7 | 1,7 | 1,2 |
| MELA apteeraus+"VMI12 cutting residue" | 3,0 | 3,5 | 3,2 |
A finite number of alternative management schedules were automatically simulated for NFI plots with MELA2016 (Hirvelä ym. 2017). Simulations were based on tree level natural process models for ingrowth, growth and mortality (e.g. Hynynen et al., 2002) and feasible (sound and acceptable) stand level management actions. Possible management actions were thinnings based either on number of trees or on basal area, final fellings (clear cutting and seed tree cutting), preparation of regeneration areas, natural and artificial regeneration, and tending of young stands. Energy wood (forest chips) were harvested as logging residues (branches and tops, or branches, tops and stumps) from final fellings or as whole trees or trunks from thinnings integrated with roundwood logging or as separate energy wood logging). Management actions were simulated when the criterias of current Finnish silvicultural guidelines (Äijälä et al. 2014), the guidelines for peat lands (Ruotsalainen, 2007) or the guidelines for energy wood logging (Koistinen et al. 2016) were satisfied. Regeneration was simulated when growing stock achieved either the minimum diameter or minimum regeneration age based on 2-4 % revenue requirement. For each management activity there was also always a no-treatment alternative. Management actions were simulated only on the forest land available for wood production. For forest land with restricted availability for wood production only intermediate fellings were possible – final fellings were not allowed. No management actions were allowed on protected forests and no cuttings were made on poorly productive forest land even if the wood production was allowed. Prescribed burning, drainage of new areas, fertilization or pruning were not included in the management alternatives.
Calculations concerning industrial wood (logs and pulp) were made using roadside prices. Roadside prices were induced by adding average realized harvesting costs on stumpage prices. Used stumpage prices are based on the average realized stumpage prices 2009-2018 (€/m3) by timber assortments (http://stat.luke.fi/en/metsa, accessed 15.8.2019) deflated to the year 2018.
Applied stumpage and road-side prices, €/m3. Birch pulpwood prices were used for saw logs and pulpwood of aspen and for other broadleaved species the stumpage prices of the 1st thinnings of birch were used which were on the average 2.9 €/m3 lower than the average price of birch pulpwood.
| Stumpage price, €/m3 | ||||||
| Province | Saw log | Pulpwood | ||||
| Pine | Spruce | Birch | Pine | Spruce | Birch | |
| Uusimaa | 59,60 | 60,70 | 44,35 | 16,30 | 19,85 | 16,45 |
| Varsinais-Suomi | 60,00 | 60,55 | 40,35 | 17,40 | 20,10 | 16,85 |
| Satakunta | 60,05 | 60,80 | 39,50 | 17,40 | 20,35 | 17,05 |
| Kanta-Häme | 60,15 | 61,30 | 44,45 | 16,45 | 20,05 | 16,65 |
| Pirkanmaa | 60,25 | 61,80 | 42,15 | 16,90 | 20,10 | 16,70 |
| Päijät-Häme | 60,40 | 61,25 | 45,15 | 16,50 | 19,95 | 16,65 |
| Kymenlaakso | 60,60 | 61,00 | 44,85 | 17,10 | 19,90 | 16,50 |
| South Karelia | 60,95 | 60,95 | 45,65 | 17,20 | 19,80 | 16,50 |
| Etelä-Savo | 60,60 | 61,15 | 47,75 | 17,05 | 19,15 | 16,60 |
| Pohjois-Savo | 58,10 | 60,30 | 44,50 | 16,65 | 18,60 | 16,55 |
| North Karelia | 58,90 | 59,45 | 45,10 | 16,75 | 18,40 | 16,00 |
| Central Finland | 59,75 | 61,60 | 45,10 | 17,15 | 19,85 | 16,80 |
| South Ostrobothnia | 59,30 | 60,25 | 39,95 | 17,85 | 20,05 | 17,75 |
| Ostrobothnia | 59,90 | 59,40 | 37,85 | 17,60 | 20,00 | 17,35 |
| Central Ostrobothnia | 59,40 | 59,75 | 40,60 | 17,95 | 20,40 | 18,00 |
| North Ostrobothnia | 56,70 | 57,45 | 39,55 | 17,50 | 19,45 | 17,40 |
| Kainuu | 56,20 | 56,75 | 42,75 | 16,60 | 18,75 | 16,05 |
| Lapland | 52,10 | 51,20 | 16,95 | 17,00 | 19,25 | 16,35 |
| Aland | 40,95 | 40,95 | 38,20 | 15,95 | 15,95 | 12,35 |
| Harvesting cost,€/m3 | 7,80 | 14,30 | ||||
The used prices (€/m3) for forest chips at the mill yard are weighted means deflated to 2018 based on 2009 - 2018 realized average prices, €/Mwh (Statistics: Energy prices, accessed 15.8.2019). The Mwh prices are transformed to cubic meters by multiplying them with 2.
| Particle | Price at the mill yard, €/m3 |
| Trunk | 42,60 |
| Branches | 42,60 |
| Stumps and roots | 42,60 |
The applied unit prices (€/h) of roundwood logging. Prices include wages, social costs, compensations for tools, profits of entrepreneurship.
| Task | Unit price, €/h |
| Forest haulage | 75,00 |
| Harvest | 100,00 |
| Manual logging | 28,35 |
The applied unit prices (€/h) for energy wood procurement. Prices include wages, social costs and compensations for tools. No subsidies for energy wood logging and chipping in young stand improvement thinnings were taken into account.
| Task | Unit price |
| Forest haulage, €/h | 75,00 |
| Felling with harvester, €/h | 100,00 |
| Manual felling, €/h | 28,35 |
| Stump lifting with excavator, €/h | 75,00 |
| Mobile chipper at the road side, €/h | 210,00 |
| Long-distance transport with trucks, €/h | 75,00 |
| Costs of loading and unloading of trucks, €/h | 55,00 |
| Fixed stationary crusher, €/m3 | 2,80 |
Unit prices for silvicultural tasks are calculated as the averages of realized prices 2008-2017 by tasks (http://stat.luke.fi/en/metsa, accessed 15.8.2019) deflated to the year 2018.
Applied unit prices of silvicultural work
| Task | Southern-Finland | Middle Finland | Ostrobothnia region | Northern Finland |
| Harrowing and scarification , €/ha | 279,00 | 252,00 | 222,0 | 195,00 |
| Ploughing and mounding, €/ha | 391,00 | 381,00 | 372,00 | 313,00 |
| Cost on pine seeds, €/ha | 244,00 | 264,00 | 221,00 | 207,00 |
| Pine seedling, €/plant | 0,15 | 0,15 | 0,15 | 0,15 |
| Spruce seedling, €/plant | 0,17 | 0,17 | 0,17 | 0,17 |
| Birch seedling, €/plant | 0,30 | 0,30 | 0,30 | 0,30 |
| Supplementary pine seedling, €/plant | 0,18 | 0,18 | 0,18 | 0,18 |
| Supplementary spruce seedling, €/plant | 0,26 | 0,26 | 0,26 | 0,26 |
| Supplementary birch seedling, €/plant | 0,40 | 0,40 | 0,40 | 0,40 |
| Silvicultural work, €/h | 21,53 | 21,35 | 21,35 | 21,35 |
| Prevention of grass, €/ha | 309,00 | 283,00 | 295,00 | 273,00 |
| Clearing and tending, €/h | 28,35 | 28,35 | 28,35 | 28,35 |
| Supplementary drainage, €/ha | 209,00 | 172,00 | 195,00 | 163,00 |
| Planning and supervision, €/h | 21,35 | 21,35 | 21,35 | 21,35 |
Southern Finland: provices 1-10 and Aland
Middle Finland: provinces 11-13
Ostrobothnia region: provinces 14-16
Norhern Finland: provinces 17-19