Biodiversity and Conservation of Plants in Brazil

Abstract:  With more than 56,000 species (excluding fungi), Brazil has one of the richest floras in the world—nearly 19% of the world flora. Our knowledge of the diversity and status of nonvascular plants in Brazil is still fragmentary, although localized studies on algae have revealed loss of species resulting from environmental pollution. Emphasis on local floral surveys, rather than wider taxonomic studies, has obscured estimates of national totals for most taxonomic groups. Knowledge of angiosperms, especially monocotyledons (of which 45% of the species are endemic), is more complete than most. For this group figures are more reliable, with some distribution patterns, endemism levels, and centers of diversity identified. Much, however, still awaits discovery. Coordinated efforts to catalog Brazil's flora are in progress and include projects such as the conservation priority-setting workshops of the Brazilian Ministry of the Environment, which have identified key conservation areas in the major biomes; development of threatened species lists for plants; and the assembly of type data on species of northeastern Brazil through the Darwin Initiative—all of which greatly assist in increasing our knowledge. These initiatives also underline the urgent need to expand the numbers and geographic spread of projects on plant systematics and taxonomy in Brazil, a measure that demands adequate provision of funding and training programs for plant specialists. Finally, Brazil's environmental agency (IBAMA) could play a proactive role in opening protected areas under its jurisdiction, thereby facilitating botanical research by university departments and research institutes.     

ASSAULT PREVENTION AS SOCIAL CONTROL: WOMEN AND SEXUAL ASSAULT PREVENTION ON URBAN COLLEGE CAMPUSES

Sexual assault on U.S.A. college campuses is increasingly recognized as an urgent and pervasive national problem. To prevent assault, school administrators and individual women promote and adopt safety strategies that often compromise women's free and independent use of the campus environment. Such strategies may fail to correspond to the actual nature of sexual assault on campus. Based on open-ended interviews with college personnel and women students, this study examines sexual assault and personal crime prevention strategies at two midwestern, urban universities. School and individual strategies are characterized according to type, goals, and orientation. Findings explore the relationship of strategies to sexual assault on campus, and implications of strategies for women's use of public space. Conclusions suggest means to increase real safety while enhancing women's freedom and mobility on and near campus.     

Successional changes in plant resistance and tolerance to herbivory

Despite considerable research on plant defenses, we know very little about how temporal changes in the environment may influence resistance and tolerance levels, or the costs and benefits of these defense strategies for long-lived plant species. We hypothesized that, in successional habitats, predictable environmental changes should favor strong plasticity in defense phenotypes and that the costs, benefits, and levels of tolerance and resistance will change with environmental context. Using a widely distributed, old-field perennial, late goldenrod (Solidago altissima), we conducted a field experiment to test these predictions. We planted goldenrod genets exhibiting varying levels of resistance and tolerance into three early-successional and three late-successional fields (approximately three and 15 years in age, respectively) and experimentally measured resistance and tolerance levels and their associated costs and selection coefficients. We found a significant effect of successional stage but no effect of genotype or stage-genotype interaction on defense levels. Genets planted in early-successional fields appeared to be more resistant and less tolerant to herbivory than those same genets planted in late-successional fields. There were significant trade-offs between resistance and tolerance in early-successional fields but not in late-successional fields. Each late-successional field exhibited a significant cost or selection gradient for resistance, but there was no general pattern of resistance costs or selection gradients specific to a successional stage class. In contrast, there was evidence of stage-specific costs of tolerance; late-successional fields exhibited significant costs of tolerance whereas early-successional fields did not. There was no evidence of direct selection for or against tolerance in either stage. Our results suggest that defense phenotypes might change in qualitative ways during succession. High resistance in early stages may be attributed to associational effects of the early-successional community, reducing the probability of damage, and despite a cost of tolerance in late stages, tolerance may be beneficial in mitigating the effects of both herbivory and environmental stresses (i.e., low light availability) that limit fitness in these fields. This study provides experimental evidence that succession can strongly influence defense phenotypes and promote temporal variability in relative resistance and tolerance levels.