Fatores que influenciam a germinação de sementes podem modular a distribuição de plantas em ecossistemas montanos

Abstract

In Chapter 1, we evaluated which factors interfere with species-specific seed germination in a restricted ecosystem, the campo rupestre. The species were delineated using the species endemic to the campo rupestre of southern tropical mountains. From this, a quantitative literature review was conducted to investigate what effects were studied and what the germination responses were for each rupestrian field endemic species. The product of chapter 1 was chapter 11 of the book to be released in 2023 by Vozes Editora, entitled "Ecologia e sustentabilidade no campo rupestre" in the Portuguese language. In Chapter 2, the potential impact of anthropogenic modifications that elevated temperature (temperature increase) and that promote land use change, such as land disturbance (continuous absence of light) on the germination of native (endemic and non-endemic) and alien seeds present in a restricted ecosystem was evaluated. For this purpose, since the endemic vegetation of campo rupestre is restricted to a montane environment, this ecosystem was again used to delimit a restricted ecosystem cut-off. From this, we sampled the literature and tested in a quantitative meta-analytical manner the response of germination tests that investigated the effects of increased temperature and total absence of light on seed germination of each species in the campo rupestre. The product of chapter 2 is an article that will be submitted to the “Journal of Mountain Science” after the adjustments suggested in the manuscript by the reviewers. Chapter 3 discusses the effect of edaphic and biotic filters on seed germination and initial growth of two congeneric species of distribution wide, with different proliferation histories in habitats modified for land use: Copaifera langsdorffii e Copaifera oblongifolia. C. langsdorffii is a native tree without a history of exacerbated proliferation present in campo rupestre and other Brazilian vegetation formations. C. oblongifolia is a native shrub with a history of exacerbated proliferation in areas of the cerrado modified for agriculture (usually at the base of the mountains that support campo rupestre). Thus, we collected se species' seeds and performed two bioassays to test edaphic and biotic filters on germination. In the first bioassay (edaphic filters, free of fungi proliferation), we used seeds buried or not in nutritionally different soils in a germination experiment. In the second bioassay (biotic filters, with fungi proliferation), we used seeds with and without aryl free of damage and damaged seeds without aryl (with low and high-intensity insect damage). The product of chapter 3 was an article submitted to the “Tropical Ecology” journal.