Invasion of Pinus halepensis from plantations into adjacent natural habitats

摘要: Questions: Do invasions of P. halepensis (Aleppo pine) from plantations into adjacent natural communities occur in the Mediterranean region, where species is native? What are spatio-temporal processes involved pine contrasting and semi-arid climatic regions? Location: regions Israel. Methods: The density invading Pinus was measured relation to distance plantation edge. Plants were categorized by age, height, basal stem girth developmental stage, their spatial distribution also recorded. Results: Analysis plant age indicates that invasion process started when 20-25 years old. Most plants found within 20 m edge, but a few individuals reached distances up 100 became new foci. Plant declined sharply with adult trees, data showing better fit power model than negative exponential model. Invading began produce cones earlier region (9 vs 12 50% reproductive plants). In both regions, higher densities on west side plantation, opposite direction hot winds prevail during seed release. Conclusion: frontal advance relatively slow, populations expand saltation process, creating spreading ‘islands’ trees vegetation. Spatial pattern recruits source population remarkably similar dispersal same (Nathan et al. 1999). This implies probability dispersed developing independent forest