Structural aspects and floristic similarity among tropical dry forest fragments with different management histories in northern Minas Gerais, Brazil

Abstract

-In order to produce useful knowledge to the initiatives of protection and management of forest fragments, more specifically for tropical dry forests which suffer with frequent anthropic activities, and due to the lack of specific studies, this article aimed describe the structure and the floristic similarity among three areas of dry forest with different management histories. The study was developed in Capitão Enéas municipality, Northern Minas Gerais, Brazil, where three fragments were evaluated, being one in regeneration for 30 years, another submitted to occasional fire and the third with selective cut in small scale. The sampling was developed through the point quarter method considering all the alive phanerophyte individuals with circumference at breast height (CBH) > 15 cm. In the three fragments, 512 individuals, distributed in 60 species, 47 genera, and 23 families were sampled. The most representative families were Fabaceae (26), Anacardiaceae (4), Bignoniaceae (3) and Combretaceae (3). However, fourteen families were represented by only one species. Only eight species were common to all fragments -Myracrodruon urundeuva standed out with 26.9% of all sampled individuals -while a great number of species were exclusive of each fragment. The floristic and structural differences between the fragments are possibly related to the history and intensity of management in each area besides the topography variations and the presence or absence of limestone outcrops. These results show the importance of each fragment, indicating that the loss of anyone would cause negative impacts on the regional flora and consequently to the associated biodiversity. ASPECTOS ESTRUTURAIS E SIMILARIDADE FLORÍSTICA ENTRE FRAGMENTOS DE FLORESTA TROPICAL SECA COM DIFERENTES HISTÓRICOS DE MANEJO NO NORTE DE MINAS GERAIS, BRASIL

Landforms and soil attributes determine the vegetation structure in the Brazilian semiarid

“…Steep slope forests do not accumulate large biomasses (in terms of basal area and canopy height) as do similar vegetation forms growing on flat surfaces (Scariot and Sevilha 2005;Arruda et al 2011). Although mountain slopes are generally richer in nutrients, these environments are also unstable and prone to erosion, with shallow soils that constrain root development; landslide erosion is also common after torrential rains under this climate type.…”

Germinação de sementes de três espécies de Fabaceae típicas de floresta estacional decidual

“…É possível que a pressão causada por esses insetos predadores às populações de A. polyphylla e B. cheilantha selecione os indivíduos com alta produção de sementes viáveis, a fim de compensar as sementes atacadas. Além disso, outro fator controlador da predação está na interação encontrada entre os predadores e seus parasitas em seu ambiente natural não impactado, possibilitando o pleno desenvolvimento das populações de A. polyphylla e B. cheilantha típicas das florestas decíduas (Arruda et al, 2011) e formações da Caatinga (Barbosa, 2003;Queiroz, 2006).…”

Soil Seed Bank at Different Depths and Light Conditions in a Dry Forest in Northern Minas Gerais

“…Moreover, most of the seed bank is represented by seeds from herbaceous species (Garwood, 1989;Baider et al, 2001), which were not considered in the floristic studies carried out in MSSP. Additionally, the high abundance of C. leptophloeos, a pioneer tree species (Carvalho, 2008), characteristic of dry forests in the region (Santos et al, 2007;Sales et al, 2009;Arruda et al, 2011) and of the arboreal component of the studied forest (Madeira et al, 2009;Nunes et al, 2013), suggest that this species uses the seed bank as a reproductive strategy.…”