29 research outputs found
The interspecific growth–mortality trade-off is not a general framework for tropical forest community structure
Resource allocation within trees is a zero-sum game. Unavoidable trade-offs dictate that allocation to growth-promoting functions curtails other functions, generating a gradient of investment in growth versus survival along which tree species align, known as the interspecific growth–mortality trade-off. This paradigm is widely accepted but not well established. Using demographic data for 1,111 tree species across ten tropical forests, we tested the generality of the growth–mortality trade-off and evaluated its underlying drivers using two species-specific parameters describing resource allocation strategies: tolerance of resource limitation and responsiveness of allocation to resource access. Globally, a canonical growth–mortality trade-off emerged, but the trade-off was strongly observed only in less disturbance-prone forests, which contained diverse resource allocation strategies. Only half of disturbance-prone forests, which lacked tolerant species, exhibited the trade-off. Supported by a theoretical model, our findings raise questions about whether the growth–mortality trade-off is a universally applicable organizing framework for understanding tropical forest community structure
Temporal population variability in local forest communities has mixed effects on tree species richness across a latitudinal gradient
Among the local processes that determine species diversity in ecological communities, fluctuation‐dependent mechanisms that are mediated by temporal variability in the abundances of species populations have received significant attention. Higher temporal variability in the abundances of species populations can increase the strength of temporal niche partitioning but can also increase the risk of species extinctions, such that the net effect on species coexistence is not clear. We quantified this temporal population variability for tree species in 21 large forest plots and found much greater variability for higher latitude plots with fewer tree species. A fitted mechanistic model showed that among the forest plots, the net effect of temporal population variability on tree species coexistence was usually negative, but sometimes positive or negligible. Therefore, our results suggest that temporal variability in the abundances of species populations has no clear negative or positive contribution to the latitudinal gradient in tree species richness
Interdisciplinary management of a patient with advanced dental needs
The present case report outlines the interdisciplinary management of an adult patient presenting with advanced generalised periodontal attachment loss, an upper dental midline discrepancy following the previous extraction of the upper left central incisor, and significant lower arch crowding. The endodontic and periodontal condition was stabilised prior to the commencement of fixed appliance orthodontic treatment and subsequent prosthetic replacement of the upper left central incisor. Interdisciplinary management provided a functional occlusion and stability of the periodontal condition along with pleasing facial and smile aesthetics