Search

ABSTRACT Soil nutrients are one of the main drivers of plant species composition and distribution, mainly due to the role they play in plant survival and reproductive success. However, the nutritional requirements of plants inhabiting their native ecosystems are still poorly known. This is the case for most species of campo rupestre vegetation, which are found on infertile soils of quartzitic and ferruginous origin. The present study evaluated the effects of macronutrients and substrates on survival and growth of the micro-endemic Vellozia nanuzae (Velloziaceae). Plant mortality was about 95 % higher in soil enriched with macronutrients and almost 100 % in soils with added manure in the first 30 days. Individual plants from treatments with added nutrients had lower growth (53 % less) compared to individuals on natural substrates. In conclusion, Vellozia nanuzaesurvived and developed better on soil of its original habitat even though it is acidic and poor in nutrients. Our results show that more nutrients are not always better for the survival and development of native species that inhabit harsh ecosystems.

ABSTRACT The growth-survival trade-off hypothesis states that functional traits of stem, wood, leaves and fruits govern acquisitive and conservative strategies of plant species that grow/survive differently in forests. We aimed to determine whether heterogeneity during the colonization of a secondary Atlantic Forest fragment causes differences in colonization-related traits and determines taxonomic composition of subplots. A total of 5,078 subplots were censused with leaf and fruit traits and height measurements being determined for each tree of each species, and with averaged-abundance-weighted values calculated for each subplot. A dendrogram was generated from the taxonomic composition of subplots using Sorensen similarity and UPGMA clustering. A total of 74,335 trees of 178 species were recorded. Clustering revealed five main groups of subplots that were tested against each other and found to differ in terms of average leaf width, leaf-width/petiole-width, wood density, mean height, height mode, fruit width and fruit length. Greater leaf averages in subplots were associated with greater fruit averages, and with higher wood densities and greater heights among groups of subplots, revealing that heterogeneity during colonization directed the communities of the 50-ha plot. The averaged values of functional traits detected subplots associated with conditions favorable to colonization, thereby reinforcing the growth-survival trade-off hypothesis.