Table 1. The different management regimes applied in our study area in central Finland (adapted from Mönkkönen et al. 2014).
Management regime Acronym Description
Business as usual BAU Current recommended management: 80 year rotation on average; site preparation, planting or seeding trees, 1−3 thinnings, final harvest with green tree retention level 5 trees ha–1
Set aside SA No management, no timber production
Extended rotation (10 years) EXT10 BAU with postponed final harvesting by 10 years; lower timber NPV due to time discounting; represents a short term conservation strategy
Extended rotation (30 years) EXT30 BAU with postponed final harvesting by >30 years; lower timber NPV due to time discounting; represents a long term conservation strategy
Green tree retention GTR30 BAU with 30 green trees ha–1 left uncut at final harvest; reduced timber production; conservation oriented management used to increase structural diversity
No thinnings long rotation (final harvest threshold criteria as in BAU) NTLR BAU with no thinnings; therefore forests grow more slowly, final harvest is delayed and timber NPV is lower; average rotation length 86 years
No thinnings short rotation (minimum final harvest threshold criteria) NTSR BAU with no thinnings; final harvest criteria adjusted so that rotations do not prolong; average rotation length 77 years; lower timber NPV due to smaller size of trees at final harvest
Table 2. Potential of the landscape (43 150 ha) in central Finland to provide annual yields of collectable goods, the combined economic value of collectable goods (NPV) across a 50 year planning horizon, and costs related to collectable goods provision. Max and Min values represent the largest and smallest possible yields or NPV of collectable goods among Pareto optimal solutions that can be achieved when applying combinations of the seven alternative management regimes. Timber NPV difference is the reduction in timber NPV in the Pareto optimal sets required to achieve maximum yields (max timber NPV is 250 M€ in all cases).
  Max Min Timber NPV difference
Collectable good
Bilberry yield 331 Mg 257 Mg 75 M€
Cowberry yield 1522 Mg 1452 Mg 7 M€
Cep yield 50 Mg 44 Mg 16 M€
Collectable goods NPV 68 M€ 66 M€ 13 M€
1

Fig. 1. Curves representing outcomes of Pareto-optimal plans describing the trade-offs between collectable good yields: bilberry, cowberry, cep, the combined economic value of collectable goods, and timber revenues in our study landscape in central Finland. The X-axis shows the difference between the maximum and minimum collectable yields in relative terms. The Y-axis similarly shows the reduction in timber NPV in the Pareto optimal sets required to achieve maximum collectable yields.

Table 3. Annual yields of collectable goods on average and the economic value of collectable goods and timber (NPV) across 50 years for alternative management regimes (BAU business as usual, SA set aside, EXT10 extended rotation 10 years, EXT30 extended rotation 30 years, GTR30 green tree retention, NTSR no thinnings short rotation and NTLR no thinnings long rotation) if only one management regime is used in all stands of the study landscape in Central Finland. The largest value of alternative management regimes is given in bold. % of Max is the proportion of the values compared to the maximum value (Table 2).
  Management regime
BAU SA EXT10 EXT30 GTR30 NTSR NTLR
Bilberry (Mg)
% of Max
266
80%
277
84%
285
86%
303
92%
273
82%
223
67%
241
73%
Cowberry (Mg)
% of Max
1491
98%
1089
72%
1416
93%
1299
85%
1381
91%
1468
96%
1365
90%
Cep (Mg)
% of Max
42
85%
35
70%
43
85%
36
71%
44
89%
42
84%
41
82%
Collectable goods NPV (M€)
% of Max
67
98%
54
79%
64
93%
60
88%
63
93%
65
95%
62
91%
Timber NPV (M€)
% of Max
246
98%
0
0%
230
92%
186
74%
240
96%
242
97%
238
95%
Table 4. Changes in %-units in the share of different management regimes (BAU business as usual, SA set aside, EXT10 extended rotation 10 years, EXT30 extended rotation 30 years, GTR30 green tree retention, NTSR no thinnings short rotation and NTLR no thinnings long rotation) in the Pareto optimal set at the 5% level of collectable good costs (95% of the maximum timber revenues) for the different collectable goods in our study landscape in central Finland. The first row was used as the reference outcome and gives the share (in %-units) of forest area under each regime when the target is to maximize timber NPV. The following rows represent changes for each regime from the reference outcome at the 5% level of collectables costs. % of Max yield is the proportion of the yield in the Pareto optimal set at the 95% level of timber revenues compared to the potential maximum yield in the landscape (see Table 2). Impr. in yield is how large improvement in yields can be gained if timber NPV is reduced of 5% from the maximum in Pareto optimal set. In the case of cowberry, values are given at the level of 97% of the maximum timber NPV when cowberry yield was already maximized.
  Management regime % of Max yield Impr. in yield
BAU SA EXT10 EXT30 GTR30 NTSR NTLR
  44.1 0.1 8.6 0.3 6.9 36.1 3.9
Bilberry 1.5 0.9 8.1 7.9 4.8 –24.1 0.9 92% 15%
Cowberry 15 0.0 –5.8 0.9 –6.6 –5.5 1.6 100% 5%
Cep –22 0.2 3.9 4.2 25.4 –13.1 1.5 100% 13%
Collectable goods NPV 16.7 0.9 –5.3 2.9 –6.8 –5.4 –2.9 100% 4%
2

Fig. 2. The proportions of the landscape area in central Finland allocated to different management regimes (BAU business as usual, SA set aside, EXT10 extended rotation 10 years, EXT30 extended rotation 30 years, GTR30 green tree retention, NTSR no thinnings short rotation and NTLR no thinnings long rotation) corresponding to the Pareto optimal solutions when optimizing (A) bilberry, (B) cowberry, (C) cep and (D) the economic value of collectable goods vs. the economic value of timber production. The Y-axis describes the share of the landscape area each management regime is allocated to, while the X-axis represents the value of the corresponding collectable good. The left-hand end of the X-axis corresponds to the solution where timber revenues are maximized and the right-hand end of the X-axis corresponds to where a collectable good is maximized.