Evaluation of management models in a trial of Castanea sativa Mill. coppice in Northern Portugal

• Autor(a) principal: Iamshchikov, Vladislav
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10198/14437
• topic: Sweet chestnut; Silviculture; Height-diameter equations; Timber production; Sustainable management models; Domínio/Área Científica::Ciências Agrárias::Agricultura, Silvicultura e Pescas

The sweet chestnut (Castanea sativa Mill.) is a valuable species in Portugal, namely in Northeast region, for both fruit and timber. So, a differentiation of management options is needed as an alternative to the traditional practices. The main target of our study was to evaluate three different silvicultural management models that have been tested since 1994 in a trial established in “Serra da Padrela” (41º 30’ 41’’N, 7º 37’ 15’’ W ), North of Portugal. This trial is composed by four permanent plots established in a coppice that resulted from the final cut of a sweet chestnut high-forest stand in 1992. These silvicultural management models aim to produce wood of small (P1 = Model 1), medium (P2 = Model 2) and large (P4 = Model 3) dimensions. A control plot was established without any type of silviculture which corresponds to the most of the existing chestnut coppices (P3 = without intervention). At 24 years old, we analyze the growth and yield under different management models as well as the potentiality to produce timber. Height-diameter equations were fitted to improve the existing equations. Dendrometrical measurements were made in all plots in the dormancy of 2016/2017. The evolution of main stand variables over time, under the different silvicultural management models, was analyzed and compared to respective reference models. The results show that Model 1 is in accordance to the expected values in reference models (mean diameter 14-25 cm at 25-30 years). In the plot without intervention the same basal area of plot 1 is obtained (G 30.9 m2 ha-1) but with an inferior quadratic mean diameter. In this plot there is a natural reduction in the number of shoots almost equivalent to that imposed to P1 by thinnings. Relatively to mortality, a strong reduction of density was observed in plot 3 due to the high competition. In Models 2 and 3 the observed growth follows closely the expected for this growth stage of the coppice. The quality of the individual shoots for wood is clearly superior to that of the plot without intervention although the dominant trees may have similar growth rates. Comparing the mean dendrometric values, higher values were observed in plots with the models application. The results also show that when the wood is to be used for saw-timber, silvicultural intervention is essential.