Maria Salete Marchioretto

Fenologia de espécies arbóreas zoocóricas em uma floresta psamófila no sul do Brasil

Biological phenomena are subject to abiotic factors that change according to geographical position, especially those related to environmental seasonality. This study provides a two-year assessment of vegetative and reproductive phenophases for nine species in a coastal forest on sandy soil in Southern Brazil. Changes in leaf fall, leaf flush, flowering and fruiting of trees from different locations within the fragment were evaluated. Leaf fall was higher in July and it was correlated with lower monthly average temperature and shorter day length. There was an increase of flushing rates after the highest leaf-fall activity from September to November. Flowering and fruiting had different rhythms; flower production was highest in October while fruit production was highest in November. The lack of a dry season suggests species do not experiment water-deficiency at regular intervals. On the other hand, vegetative and reproductive phenophases were related to variations in average temperature and day length throughout the year.

Problemas de conservação das espécies dos gêneros Froelichia Moench e Froelichiella R.E. Fries (Amaranthaceae) no Brasil

The state of conservation of the representatives of the genera Froleichia Moench and Froelichiella R.E. Fries (Amaranthaceae) in Brazil is discussed based in the criteria of International Union for Conservation of Nature and Natural Resourses (IUCN). Most of the species can be considered as vulnerable, but may also present more serious problems on a regional basis, while some species should be considered as probably extint (EX), criticaly endangered (CR) or endangered (PE) at least in large part of their original distribution range.

Amaranthaceae as a Bioindicator of Neotropical Savannah Diversity

Brazil is the first in a ranking of 17 countries in megadiversity of plants, having 17,630 endemic species among a total of 31,162 Angiosperm species [1], distributed in five Biomes. One of them is the Cerrado, which is recognized as a World Priority Hotspot for Conservation because it has around 4,400 endemic plants – almost 50% of the total number of species – and consists largely of savannah, woodland/savannah and dry forest ecosystems [2,3]. It is estimated that Brazil has over 60,000 plant species and, due to the climate and other environmental conditions, some tropical representatives of families which also occur in the temperate zone are very different in appearance [4].