Spatial patterns and interspecific associations of dominant tree species in two old‐growth karst forests, SW China

Abstract

Spatial patterns and interspecific associations of plant species in forests are important for revealing how species interact with each other and with the environment, and hence have important implications for optimal forest management and restoration in degraded forest ecosystems. In this paper, the O-ring statistics were used to characterize the spatial patterns and interspecific associations of eight dominant tree species in two 1-ha old-growth karst forest plots in Maolan National Natural Reserve, southwestern China. We found that most of the eight dominant tree species in two forests were continuously regenerating populations. Six species (Platycarya longipes, Acer wangchii, Clausena dunniana, Castanopsis carlesii var. spinulosa, Distylium myricoides, and Rhododendron latoucheae) exhibited significant aggregations at the majority of scales while others (Celtis biondii and Cyclobalanopsis myrsinaefolia) showed a random distribution pattern at most scales. Negative association was a dominant pattern for most species pairs in the two plots, while positive associations were found at most scales for only two species pairs (Platycarya-Clausena and Castanopsis-Rhododendron). Results also indicated that the two main factors of habitat complexity and heterogeneity-the elevation and rock-bareness rate-play important roles in determining spatial distribution patterns and interspecific associations of tree species in karst forests of Maolan. Thus, the observed spatial patterns among the eight tree species are influenced by habitat heterogeneity in the context of karst topographical variations. The partitioning of habitat niches contributes to the promoting species coexistence in species-rich karst forests. The differences of species features in spatial patterns and associations should be paid more attention when planning forest management and developing restoration strategies.

Structural diversity of selected oak stands (Quercus roburL.) on the Krotoszyn Plateau in Poland

“…the results obtained from the two reserves are, therefore, consistent with earlier studies. the aggregations of trees encourage a spatial mosaic of habitat conditions, varied ecological and biological requirements of species and the manner of their renewal (Müller et al 2000;Wiegand et al 2007Wiegand et al , 2009Zhang et al 2010). The clustered arrangement of trees in Biadki resulted, amongst others, from the aggregate occurrence of hornbeams, which comprised 90% of quantitative share of species.…”

Point Pattern Analysis of Different Life Stages of Haloxylon ammodendron in Desert-oasis Ecotone

“…The size structure of a species reflects regeneration processes [16,17], and when compared to the spatial structure of forest, can provide insight into the forest dynamics [18]. H. ammodendron plants in the plot had a large number of seedlings, and the size distribution of H. ammodendron population appears as a reversed "J" shape, suggesting the continuous population regeneration and favorable conditions for establishment and survival of seedlings.…”

Effects of Heterogeniety on Spatial Pattern Analysis of Wild Pistachio Trees in Zagros Woodlands, Iran

“…Spatial distribution of trees in a forest stand reveals intraspecific and interspecific interactions of them and their relationships with environmental conditions, and thus it is not only a spatial property of trees but also basic quantitative characteristics of them. It also can be used to assess whether groups of trees in a forest stand show competitive or facilitative effects (Uuttera et al, 1998;Fan and Hsieh, 2010;Zhang et al, 2010;Alvarez et al, 2011;Wiegand et al, 2012). If competition is the reason of the spatial distribution of trees in a stand, the arrangement of them tends to be dispersed (i.e., uniform distances between trees), and if facilitation is of great importance, the arrangement tends to be clustered, and it is more likely random if neither facilitation nor competition effects are observed (Wiegand and Moloney, 2004).…”