Assessment of cork production in new Quercus suber plantations under future climate Joana A Paulo Margarida Tomé João HN Palma 22 May 2012 1
Introduction Climate is related to several variables that affect individual tree and stand cork production: Tree growth rates Tree vitality / mortality Cork growth rates Management options like: cork debarking rotation (period between two consecutive cork extraction operations a minimum of 9 years according to the Portuguese law) Cork debarking intensities (maximum values regulated by the Portuguese law) 2
Introduction SUBER Tree dimention Site index Climate Tree mortality Tree and cork growth Manage ment Soil Cork growth
Introduction Process based models (e.g. Yield-Safe, 3PG) Average tree dimention Tree mortality Soil Tree growth Climate Cork growth Managem ent
Objectives Explore a methodology that allows the hybridization of the Yield-Safe big leaf process based model and the empirical individual tree growth model for Quercus suber L.: SUBER model Simulate stand growth and stand cork production variations under future climate, in new plantations 5
tree volume (m 3 /tree) dbh (cm) Material and Methods Yield-Safe calibration for tree potential dbh, volume and biomass growth using: dbh (tree rings measurements on stem discs) Volume and biomass measures (dots) 3.0 2.5 2.0 1.5 1.0 0.5 0.0 70 60 50 40 30 20 10 0 0 10 20 30 40 50 60 70 80 90 100 Age (years) 0 10 20 30 40 50 60 70 80 90 100 age 6
Material and Methods Assumptions for Yield-Safe simulations: The number of trees per hectare in the stand at 15 years of age, is equal to the number of trees per hectare measured in the forest inventory in 2007 New plantations are managed for cork production: high number of trees per hectare no agro or pastoral activities no fertilization no irrigation periodical understory removal 7
wcm (kg) Material and Methods SUBER allometric equation for tree cork production depending on: tree size variables (dbh and number of main branches) management options variables (debarking intensity) Estimates of cork production assume: Debarking intensity equal for all trees in the stand 9 year interval between consecutive cork extractions in the same stand 250 225 200 175 150 125 100 75 50 25 0 0 10 20 30 40 50 60 70 80 90 100 110 dbh (under cork) (cm) 8
Material and Methods Data from 2 cork oak plantations installed in 1992 and measured in 2007 (15 years old stands): Soil information: Texture Soil depth Number of trees per hectare at plantation Forest inventory data collected in 2007: Diameter at breast height Total heigh No cork inventory data (cork thickness or cork quality) in 2007 stands had still not been debarked 9
Material and Methods Coruche (Inland) Arenosols Medium soil texture 135 cm soil depth Sines (Seashore) Luvisols Fine soil texture 150 cm soil depth 10
Material and Methods Climate daily data: total shortwave radiation precipitation mean temperature Data source: HadRM3Q0 A1B (ENSEMBLES EU project: Hadley Center Regional Model Normal sensitivity) IPCC scenario A1B Daily data from 1951 to 2099: 1951-2000 2001-2050 2050-2099 11
Monthly precipitation (mm) Average temperature (ºC) Material and Methods 30 25 Coruche (inland) + 3.4 ºC 20 15 10 Tmean 1951-2000 Tmean 2050-2099 5 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Month 120 100 80 Coruche (inland) -27 % 60 40 Prec 1951-2000 Prec 2050-2099 20 0 1 2 3 4 5 6 7 8 9 10 11 12 Month 12
Monthly precipitation (mm) Average temperature (ºC) Material and Methods 30 25 20 Sines (seashore) + 2.9 ºC 15 10 Tmean 1951-2000 Tmean 2050-2099 5 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Month 140 120 100 Sines (seashore) - 20% 80 60 40 Prec 1951-2000 Prec 2050-2099 20 0 1 2 3 4 5 6 7 8 9 10 11 12 Month 13
Hybridization scheme Yield-Safe Soil and climate variables Assimilation of carbohydrates (crop) Assimilation of carbohydrates (tree) t1 year corresponding to age 15 of the stand (age in during the forest inventory) Stand basal area annual increment ig ti+1 = G ti+1 - G ti Tree basal area growth ig ti+1 = (g ti / G ti ) * ig ti+1 SUBER Tree cork production Total above ground tree biomass Stand basal area (G t ) Tree diameter under cork Stand cork production
Basal area (m2/ha) Basal area (m2/ha) Results: basal area evolution 25 20 Coruche 15 10 1951-2000 2001-2050 2050-2099 5 0 0 10 20 30 40 50 Age (years) 25 20 Sines 15 10 1951-2000 2001-2050 2050-2099 5 0 0 10 20 30 40 50 Age (years) 15
Mature cork production (kg/ha) on each cork extraction Mature cork production (kg/ha) on each cork extraction Results: mature cork production The effect of climate scenario on cork production differs between the two sites: Reduction of cork production in Coruche (inland) No large variation of cork production in Sines (seashore) 7000 6000 5000 4000 3000 2000 Coruche 2210 2096 2191 4550 4274 4070 6258 5686 5310 6000 5000 4000 1951-2000 2001-2050 3000 2050-2099 2000 Sines 2726 2548 2577 4366 4442 4430 5485 5476 5342 1951-2000 2001-2050 2050-2099 1000 1000 0 1st debarking 2nd debarking 3rd debarking 0 1st debarking 2nd debarking 3rd debarking 16
Mature cork production (kg/ha) along 50 years Results: mature cork production Mature cork production variation along the 50 years simulation period: Until less 11% in cork production in Coruche considering the 2050-2099 climate data instead of the 1951-2000 data Close to zero cork production variation in Sines despite the climate data 13500 13018 13000 12399 12495 12497 12500 12000 11500 11000 12056-7% 11571-11% 1951-2000 2001-2050 2050-2099 10500 Coruche Sines 17
Results: Impacts Mitigation Adaptation Impacts: Climate will affect tree growth, and consequently, cork production, in quantities varying between sites, namely soil characteristics Climate will affect cork growth, and consequently cork thickness (cork quality?) Climate is already affecting tree mortality rates (stress, pests and diseases) Mitigation: Reduction of the debarking intensities Increase of the debarking rotation periods New plantations in land areas traditionally used for agricultural activities, with better soil characteristics Adaptation: Selection of new tree species and mixed stands more resistant and well adapted to climate conditions 18
Results: Impacts Mitigation Adaptation Increase or maintain cork production Decrease cork production 19
Future chalenges Hybrid model (individual tree) Tree dimention (YS) Tree mortality (Empirical? Tree or stand level?) Soil (YS) Cork oak hybrid model Climate Cork growth (Empirical?) Cork quality 20
Thank you 21