DAMAGES CAUSED BY FIRE ON THE NATURAL VEGETATION IN A PRIMARY FOREST IN ACRE STATE, BRAZILIAN AMAZON

• Main Authors: Henrique José Borges de Araujo, Luis Cláudio de Oliveira, Sumaia Saldanha de Vasconcelos, Manoel Freire Correia
• Format: Article
• Language: Portuguese
• Published: Universidade Federal de Santa Maria 2013-06-01
• Series: Ciência Florestal
• Subjects: floresta amazônica; queimadas; incêndios florestais
• Online Access: http://cascavel.ufsm.br/revistas/ojs-2.2.2/index.php/cienciaflorestal/article/view/9276
• ISSN: 0103-9954; 1980-5098

<span lang="EN-US"><a>http://dx.doi.org/10.5902/198050989276<br /></a><br />The emission of CO₂ is an important cause of the greenhouse effect and the Amazonian burns contribute to it. Because of the high moisture retained, the primary Amazon forest is considered immune to fire, however, <span class="mediumtext">under abnormal climate conditions it is vulnerable</span>.</span><span lang="EN-US"> The objective of this study is to evaluate the effects of fire, originated from forest-fires occurred in 2005, in a natural primary forest in the state of Acre, Brazilian Amazon region.<span> The effects of fire on trees, palm trees and lianas were evaluated in three levels of size:</span> I-DBH≥5cm; II-5cm&gt;DBH≥2cm; and III-DBH&lt;2cm and <span>height</span> ≥1,0m. T<span>he individuals were evaluated for General Condition (levels I and II), Bark and Cup (Level I) and budding. Five evaluations were made, the first in November 2005 and last in January 2009. The results showed that the smallest subjects were the most impacted ones and showed the highest mortality rates, reaching 80.1% for Level II and decreasing  according to the increasing size of the tree and it is null (0%) in higher classes. It was observed a growing number of individuals with no apparent damage in all diameter classes and a 43% increase in the number of species in <span lang="EN-US">regeneration, indicating a recovery process of the forest. It was observed a significant reduction of species diversity (15% in Level I and 33% in Level II), showing that the forest was modified in its floristic composition. Based on the significant damage caused by only one fire, the case of study, it is expected the incidence of new fires, at short intervals insufficient for the recovery and it will promote the irremediable degeneration of forest.</span></span></span>