Studying within-stand structure and dynamics with geostatistical and molecular marker tools uri icon

abstract

  • We established a circular experimental plot (radius = 100 m) that consists of 380 trees of maritime pine (Pinus pinaster Ait.). The plot is located in central Spain (Segovia province) and within a pure, even-aged and naturally regenerated stand of the species. Every tree was initially mapped using polar coordinates. The objective of the study was to explore the spatial arrangement of some stand attributes such as age of trees, diameter at breast height (DBH), total height, diameter increment and number of female strobili and cones. Genetic data (three highly polymorphic nuclear microsatellites) were used to investigate extend of relatedness within the stand and differentiate between genetic and environmental causes of spatial aggregation. We employed, in the analysis of tree attributes, only geostatistical tools (direct and cross variograms as well as their indicator counterparts). The results revealed that all the studied attributes are spatially correlated and some of them cross-correlated. Competition and height were found to be key-variables in stand dynamics, which influence the rest of the attributes. Fine-scale genetic structure exists within the stand (0-30 m range). Relatedness between neighboring trees can partially explain the spatial aggregation of individual tree attributes. Geostatistical tools are recommended for this type of spatial analysis of forest stands. Their use can provide useful insights into the nature of stand organization and can guide future silvicultural treatment toward higher stand productivity or better and faster regeneration. (C) 2003 Elsevier B.V. All rights reserved.

publication date

  • 2004
  • 2004