Natural regeneration and nutrient cycling in a Seasonal Forest fragment dominated by Fabaceae in Alegre, ES
Name: NAIARA MACHADO NEVES
Publication date: 28/02/2018
Advisor:
Name |
Role |
|---|---|
| SUSTANIS HORN KUNZ | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| KARLA MARIA PEDRA DE ABREU | External Examiner * |
| SUSTANIS HORN KUNZ | Advisor * |
| TIAGO DE OLIVEIRA GODINHO | External Examiner * |
Summary: After centuries of devastation, the Atlantic Forest was limited to fragments that vary in size, shape and use history within a matrix dominated by anthropic activities. The Fabaceae family stands out in the tropical formations for their great wealth and to function as a primary source of nitrogen due to biological fixation through association with bacteria. The present study had the following objectives: 1) to characterize the structure (richness and diversity) of the natural regeneration and to indicate the changes that occur in legume species in a fragment of the Seasonally Dry Tropical Forest (FTSS), as well as the influence of the historical use of the soil (selective cutting of wood, coffee crop and pasture) on regenerating species; 2) to estimate the leaf litter production and the seasonal contributions of carbon (C), nitrogen (N) and phosphorus (P), as well as the relative contribution of Fabaceae arboreal to these processes. The study was carried out in a fragment of 70 hectares that compose the Legal Reserve of the Environmental Education Pole of the Federal Institute of. (PEAMA), Alegre - ES. In the 1970s such a fragment was disturbed by traditional activities, such as the selective cutting of wood, and contained stretches regenerated after coffee cultivation and pasture. In the year 2013, 19 plots of 400 m2 of area (20 x 20 m) were distributed every 200 m throughout the area of the fragment in order to study the tree size. For the study of natural regeneration, 21 plots (5 x 10 m) were installed. The litter was quantified in 11 plots used in the study of tree size, whose abundance and dominance of Fabaceae were representative of the area of the fragment. With this study it was observed that the family Fabaceae was representative in the extract of the regeneration of the fragment, but in relation to the arboreal size there was a reduction in the abundance of this family, indicating that the fragment is in the process of change. There was no influence of usage histories on species distribution. In relation to the contribution of Fabaceae to the nutrient intake, it was observed that it contributed significantly to the nitrogen input in the dry season (winter) via litter. However, the deuterutrient contents were low in the 0-20 cm layer of the soil of the PEAMA fragment. Thus, it is concluded that the Fabaceae has greater representativity (abundance and dominance) in forests with initial successional stage, since it favors the development and the permanence of species through the biological fixation of nitrogen and assists in the advance of the succession of the fragment, being of great relevance in the contribution of nitrogen through litter in FTSS
Keywords: Leguminosa; Burlap and Atlantic Forest.
