“Modelling growth and pine nuts production for Pinus pinea under changing environmental conditions” is a Research Project funded by FCT, with the reference PTDC/AGR-FOR/3804/2012 and it is known in short as PINEA Project. Portugal is at the moment the country with the second largest area of stone pine (Pinus pinea), after Spain. It has 130,400 ha; the Iberian Peninsula accounts, approximately for 75% of stone pine distribution. Since 1995 this was the tree species with the highest rate of area increase in Portugal. Its recent large expansion is mainly due to its adaptability to dry environments and the high value of its edible kernels, the “pine nuts”. Due to its favourable site and climate conditions Portugal has, on average, higher nut yields per unit area than Spain. In addition, there is an increasing interest in Pinus pinea for afforestation in areas of Pinus pinaster badly affected by the pine wilt nematode.
Between 1995 and 2005 around 39 million euros have been invested in Portugal on establishing new Pinus pinea plantations. Pine nut production, in 2011, represented 22 million Euros. However, there have always been very limited funds available for research and development (R&D) for this species. Existing empirical modeling work done on Pinus pinea in relation to growth and nut yields is based on a very limited dataset. The models need to be improved significantly. No process-based model has been created for this species. This is important for two reasons: (i) there is no existing way to predict the likely effects of climate change on Pinus pinea productivity; (ii) although there is considerable interest in new planting, there is no tool to support decision-making relating to the selection of suitable areas for planting.
The main objectives of the PINEA Project are:
(i) the calibration and validation of a process-based model for Pinus pinea in Portugal. This will allow estimation of the productivity of existing stone pine plantations in the context of climate change, considering different climatic scenarios, and will provide a tool to support decision-making regarding new planting;
(ii) evaluation of the effects of irrigation and nutrient availability on Pinus pinea growth and nut yields;
(iii) to improve existing empirical modelling equations relating to growth and nut yield of Pinus pinea.
The PINEA Project will carry out nine planned Tasks. It will use existing Pinus pinea data, including data from permanent sample plots, previous biomass trials, and an established fertilization trial. A new irrigation and fertilization trial will be established. New data will be collected from it and from existing permanent sample plots and a fertilization trial. All these data will be validated and organized in databases. Following database development the data will be analyzed in different ways, bearing in mind that one of the major objectives is to develop a process-based model calibrated for Pinus pinea.
A major challenge in relation to calibrating and validating a process-based model will be assessing productivity of the main product of interest, is nut yield. This will require an innovative approach, to include carbohydrate allocation to cone/fruit biomass in a process-based model such as 3-PG. Data obtained from the irrigation and fertilization trial will be important in providing the information necessary to evaluate how Pinus pinea allocates carbon to the nuts.
The fertilization and irrigation trial will provide an understanding about how water and nutrient availability influence nut yield, root biomass, leaf biomass and stem biomass. This experiment will impose a range of conditions that are wider than the range likely to occur in practice. This will allow the researchers to assess the responses of the trees to conditions that might not normally be encountered. It would be important to impose irrigation treatments on this experiment whether or not widespread commercial irrigation of stone pine is likely in Portugal.
The PINEA Project team includes the most active researchers in forest modelling in Portugal. The consultants will provide a strong scientific input that will contribute to the success of this research project. In tree physiology and process-based modelling Dr Joe Landsberg will be bring internationally recognized scientific knowledge. Equally in silviculture Dr Peter Savill has an extensive and impressive record of research work. Dr Rafael Calama is one of the leading modellers currently working on Pinus pinea. Finally Maria Augusta Vacas de Carvalho is known in the Portuguese forestry sector as one of the most knowledgeable people in the management of Pinus pinea stands.
The PINEA Project provides a great opportunity to increase research and development (R&D) regarding Portuguese Pinus pinea forests. Without this Project it would not be possible to improve significantly existing empirical models or to create an innovative process-based model.