The goals of this research are to identify the major constraints to plant succession in degraded cerrado vegetation. The area selected for this research, is located on the right bank of the Araguaia River in Goias State (Brazil). Floristic composition survey, seed rain and soil seed bank assessments were conducted in four forest fragments and in a degraded area. Planted seedlings, Soil translocation, Seed translocation and Artificial perches were also investigated. Floristic composition survey showed a richness of 145 species for the whole area and absolute density of 623.89 individuals.ha-1 for the degraded area and a range from 1333.72 to 2247.27 individuals.ha-1 for forest fragments. Seed rain survey resulted in 87 species identified, and annual seed arrival was 2.36 seeds.m-2 for the degraded area and 103.75 seeds.m-2 to 236.25 seed.m-2 to forest fragments. Soil seedbank analysis found a richness of 33 species and 87% of germinated seeds were from non-woody plants. The mean seed density of woody plants was 0 for the degraded area and ranged from 25 seeds.m-2 to 257.50 seed.m2 for forest fragments. Introducing seedlings showed a seedling survival rate of 38% after 24 months observation. Enterolobium sp and Inga spp showed higher rates of growth and positive interaction with fertilizer. The application of Tanglefoot, showed no significant results in any treatment. Treatments with fertilizer had less herbivory registered. Luehea candicans showed higher rate of herbivory. Seedling mortality was lower in fenced blocks and indicated Inga spp with lowest rate. Amongst nucleation strategies Seed translocation recruited more individuals after two years, followed by perches and soil seed bank translocation, but perches recruited more different species and had the same rate for seedling survival when compared to seed rain translocation. The results from this study show that succession in degraded Cerrado may be constrained by biotic and abiotic barriers.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:675555 |
| Date | January 2014 |
| Creators | Santos, Gildomar Alves dos |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=228005 |
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