Habitat differentiation of Lauraceae species in a tropical lower montane forest in northern Thailand

Abstract

Dependency on topographical habitat was examined for Lauraceae tree species in a lower montane forest using a large‐scale research plot established at Doi Inthanon National Park, northern Thailand. Twenty species of 10 genera of Lauraceae were recorded in a 7.5‐ha part of the plot; Lauraceae accounted for 18% of the total basal area. Lauraceae was the most species‐rich and most abundant family in the plot. In a cluster analysis based on the matrix of spatial associations between species, two clusters were recognized. Members of one cluster seemed to associate with lower‐elevation habitats, and members of the other associated with habitats on ridges. By subdividing the study plot into 20 m × 20 m squares, a discriminant analysis could be applied to the presence–absence data for the 17 species that had sufficient population density. The predictor variables used were the relative elevation, slope inclination, slope direction (transformed to deviation from SSW) and slope convexity for each of the squares. The discriminant models were tested statistically by applying the random shift technique. The models were significant for 11 of the species (65% of the species examined) and were associated with the topographical condition of the habitat. Stepwise selection of the predictor variables for these 11 species revealed that relative elevation and slope convexity were the most important factors for predicting the presence or absence of the Lauraceae species. Both these variables were considered to indicate the hydrological condition of the habitat.

Spatial patterns and associations of dominant woody species in desert–oasis ecotone of South Junggar Basin, NW China

“…In the plots, the dominant woody species therefore coexist and are strongly associated with various habitats that require for survival and recruitment. Some studies have revealed the importance of topographical variations in determining the species coexistence (Sri-ngernyuang et al 2003;Yamada et al 2006). Our study results showed that the soil variations in the desert and oasis transition belt determine the co-occurrence of woody species after sandy desertification.…”

Water storages in plants and soils in two community forests of Karen tribe, northern Thailand

“…The montane forest is typically moist and cool. However, the plant diversity and the hydrological cycles in these forests vary with altitude and topographical habitat (Sri-ngernyuang et al 2003;Khamyong et al 2004;Withawatchutikul et al 2011). The soil in this forest was deep, classified in Order Ultisols, and contained the high content of organic matter as well as the low bulk density in surface soil with some organic layers on the forest floor (Pornleesangsuwan et al 2011).…”

Importance of soils, topography and geographic distance in structuring central Amazonian tree communities

“…Nonetheless, some environmental variables, particularly soil texture, cation composition and topography, are repeatedly reported as important in determining tropical forest composition (Costa et al 2005;Sri-Ngernyuang et al 2003;Tuomisto et al 2002;Valencia et al 2004;Vormisto et al 2004). The availability of complete floristic and soil data sets that are needed to address these questions is very limited given the vast extent of the tropics.…”