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Báo cáo lâm nghiệp: " Sweet chestnut silviculture in an ecological extreme of its range in the west of Spain (Extremadura)"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế, đề tài: Sweet chestnut silviculture in an ecological extreme of its range in the west of Spain (Extremadura). | 667 Ann Sei For 1997 54 667-680 Elsevier Inra Original article - Ulf Sweet chestnut silviculture in an ecological extreme of its range in the west of Spain Extremadura A Rubio A Escudero2 JM Gandullo 1 1 Dept Silvopascicultum ETS Montes 2Dept Biologia Vegetal. EUIT Agricola. Universidad Politécnica de Madrid. Madrid 28040 Spain Received 9 May 1996 accepted 12 November 1996 Summary- Forest management has been conducted in many sometimes opposing directions without any relevant environmental restriction. Thus sweet chestnut stands have been bidirectionally transformed alternating high forest and coppice structures with many different management aims in mind increasing economic benefits favouring biodiversity conservation improving landscape protection etc. To test whether this type of multidirectional management can be extended to the ecological edges of a typical European forest tree a study was conducted in central-western Iberian Peninsula. There chestnut forests have been exploited under traditional regimes during recent centuries. Thirty forest stands were chosen after a clustered sampling process. In each of these stands 53 variables were measured or estimated and assigned to five different data sets silvicultural climatic edaphic physiographic and floristic. The silvicultural matrix was compared with the other four by canonical correlation analysis. Almost all the data sets presented significant correlations with the silvicultural regime. Thus it was easy to conclude that the environment is constraining chestnut forest management. Coppice has historically been confined to the highest ranges of the territory which are exposed to the moist winds from the southwest. On the other hand high forests have been located in drier sites. There the forest needs to be intensively managed to avoid inter- and intra-specific competition. Under these conditions coppice stands do not prosper. The relationships between chestnut silviculture and environment were also established