1. Julia Touza-Montero and Charles Perrings Environment Department, University of York Policies for the management of landscape diversity and collectively managed forests: the case of Galicia

2. Presentation overview Motivation Multiple stand landscape model - optimal harvesting rule - Case study: Galician collective forests in Spain Policy implications

3. Motivation Management of forest resources has moved towards a landscape-based approach to manage for multiple values Think beyond individual stands -- mosaic of stands Why? Management at a stand level impedes the assessment of the implications of the management actions at a landscape scale Lack of spatial consideractions (stands size, shape, proximity, dispersion, adjacency) Unanticipated ecological changes

4. Forest management at a landscape scale is increasingly recognised as a key for conservation of biodiversity Focus on maintaining the habitats Interactions between spatially dispersed stands determine forest ecological processes (e.g. movement of species, spread of disturbances) Motivation - Cont….

5. Case study focuses on Galicia (Northwest of Spain) Forest area covers 69% of the territory Pinus pinaster, Eucalyptus globulus, and mixed forest of these species 35% Quercus robur and Quercus pyrenaica 14% Non-wooded (scrublands) 31% Galicia has patchy forest land Motivation - Cont….

6. Individual ownership: 68% of forest land- 2.3 ha mean size Collective ownership: 30% of forest land- 231 ha mean size Members of a rural community have the rights to the forest resources without parcelling the rights to the forest itself Forestry, support for cattle raising and agriculture, amenities, hunting, etc. Multiple forest uses and spatial interactions between stands are integrated within the decision making process

7. Harvest decisions, i.e. rotation periods, in a multiple stand forest managed for timber and non-timber values Stand interactions are assumed to influence the flow of non-timber benefits provided for the entire forest landscape Bowes and Krutilla, 1985, Swallow et al. 1997, Thavonen and Salo, 1999, Amacher et al. 2002 A dynamic optimal cutting rule in a multiple stand forest landscape Note: theoretical results independent of type of ownership Multiple stand model

9. Choose the optimum time moments of the stands’ harvests, to maximise timber and non-timber benefits   (s 1 [a 1 (t)],..,s n [a n (t)]) e -  t dt +  [p i x i (  ij - )-c ip x ip ] e -   ij subject to x i = F i [x i (t)] between harvests a i = 1 between harvests x i (  ij + ) - x i (  ij - ) = - x i (  ij - ) + x ip at harvest a i (  ij + ) - a i (  ij - ) = - a(  ij - ) + a ip at harvest x i (0)=x 0 T 0  

10. Optimal cutting condition for any stand in the forest landscape Forest MB = Forest MC  (s 1 [a 1 (  ij - )],., s n [a n (  ij - )]) e -   ij -  (s 1 [a 1 (  ij + )],.., s n [a n (  ij + )]) e -   ij + p i F i [x i (  ij - )] e -   ij Multiple stand model Stands’ interactions =  [p i x i (  ij - )-c ip x ip ] e -   ij + p i F i [x i (  ij+1 - )] e -   ij+1 +  i (  ij + )  (  ij - ) -  (  ij + ) stand i relative contribution to the forest NTB if its harvest is delayed  i (  ij + ) opportunity costs of delaying future forest NTB and altering the age of stand i relative to the other stands’ age

11. Analysis of harvesting decisions accounting for landscape pattern differences between collective forests Dependent variable: rotation length Baixo-Miño (68% forest land – 73% collective forests) Reports on clear-cuttings undertaken on collective forests under contract mechanisms - from 1995 to 2001 Case study: Galician collective lands

12. Coefficientp-valueCoefficientp-value N= 108 a N= 94 DV Conifer0.543***0.0000.580***0.000 Net timber prices0.582***0.0030.607*0.060 Annual difference in interest rate (IR t -IR t-1 )-0.132**0.006-0.119**0.032 Mean size of wooded patches0.465***0.0050.427**0.018 % of area occupied by mixed tree-species patches0.436***0.0000.401***0.001 Clusters of patches of identical forest characteristics-0.192**0.033-0.206**0.044 Constant2.528**0.0202.2150.106 P2.788***0.0002.6630.000 Log-Likelihood-61.80-57.42 Wald-test (p-value)0.7640.766 p-value0.000 (a) We compute this estimation with dummies for those harvesting reports which contain several tree species but the p-values suggested omitting them from the model *** significant at 1% level; ** significant at 5%; * significant at 10% Duration analysis: parameter estimates from the Weibull distribution

13.  Optimal harvesting strategies at a single-stand scale are not necessarily optimal when a larger spatial scale is adoped and spatial interactions inform the decisions What is the difference? Single-stand: the flow of the stand’s NTB influences when the stand should be harvested (Faustmann-Hartman rule) Multiple-stand: it is the relative contribution of each stand to the NTB from the overall forest landscape that affects the rotation intervals Conclusions and policy implications

14.  Fragmentation, diversity and clumpiness are relevant determinants of harvesting behaviour in Galicia collective forests  Policy implications: Non-harvesting policies may be optimal for those areas that contribute highly valuable environmental goods and services to forest landscape benefits It may be optimal never to harvest any of the stands in the forest if NTB increase with age and are significant with respect to other uses Policy implications – Cont...

15. The ecological and economic consequences of alternative actions taken at small scales (stands) on a wider spatial context (i.e. forest landscape) must be allowed for in forest management decision making The weight attached to the forest benefits from a particular stand depend on the interdependence between stands Importance of spatial interactions on harvesting strategies – Scale Policy implications – Cont...

16. In Galicia Public planning of forest landscapes is essential to account both for: (a) spatial interactions between the stands; (b) preferences of society Public policies, which encourage coordination and cooperation among forest owners, are necessary to ensure that private owners’ actions are consistent with environmental and economic goals set at a landscape level Problems: Inventories of single and collective forest ownerships are scarce Weakened communal institutions Policy implications – Cont... 98% of forest land is in private hands Individual ownerships have a mean size of 2.3 hectares

17. Thank you!