Pinus pinea cone potential production suitability map

Abstract

Interpretative cartography has been used to develop site quality models for the growth of forest species as well as their productions. For Pinus pinea it was developed a suitability map for its development in the south of Portugal, based on the interpretation of the soils and Pinus pinea ecological and cultural characteristics. Yet, Pinus pinea production varies within the areas suitable for its development. The objective of this study was the development of a cone potential production suitability map for Pinus pinea. Expert analysis, reclassification and map algebra methods anchored in a geographical information system were used to develop the map. As cone production relates to soil and climate, soil diagnostic characteristics, precipitation, temperature and Martonne index were used as input variables. Three classes were considered: reference (which corresponds to a media potential cone production), superior to reference and inferior to reference. Adequacy of the model for Alentejo and Ribatejo were assessed with Kappa statistics. The areas with the highest cone potential production are in the west and north of the study area whereas the lowest occurs in the east and south of the study area. In the areas with the highest cone potential production, the limiting factor is soil and for those with the lowest potential is climate. The model had a Kappa statistic of 0.85, corresponding to a good agreement. The suitability map for Pinus pinea cone potential production is a useful tool for selecting areas for forestation and afforestation and adapting management to improve cone production.