Forest tree spatial characteristics of a coniferous, broad-leaf mixed forest on Mount Tianmu

Abstract

To understand characteristics of forest tree spacing in a coniferous, broad-leaf mixed forest on Mount Tianmu and to provide a theoretical basis for sustainable forest management, fifteen 30 m 30 m fixed plots were established to measure characteristics of all trees over 5 cm DBH. The forest crown was used for a spatially segmented scale to generate a Voronoi Diagram, to determine the spatial unit between trees, and for statistical analysis of differences with various scales of tree spacing. Results showed that single tree spacing had large differences, with an average of four to five trees in a group. The spatial area was stable for dominant species of Castanopsis sclerophylla, Castanea henryi, and Quercus acutissima, but large spatial difference were found with Pinus massoniana, Cunninghamia lanceolata, Quercus fabric, and Symplocos caudata. DBH influenced spatial area, but not the nearest-tree number. The range of nearest-tree number for target trees was 3 to 13, with the mode being 5, 6, and 7, and the mean was 6. Overall, Mount Tianmu was a well-established, mixed forest, with a relatively stable community structure.［Ch, 8 fig. 2 tab. 25 ref.］