The Belo Horizonte Zoo-Botanic Foundation Natural Reserve, Brazil
Volume 3 Number 10 - June 2003
Juliana Ordones Rego
The Belo Horizonte Zoo-Botanic Foundation (FZB-BH) was created in 1991. It is indirectly administered by the city hall of Belo Horizonte and consists of the Botanic Garden, the Zoological Garden, the Environmental Education Service and the Administration and Finance Departments.
The Foundation has a total area of 1,450,000 m2, of which 600,000 m2 is cerrado and cerradão. It is located in Belo Horizonte, Minas Gerais (44º 01’ 00’’ W and 19º 51’ 50’’ S) and 850 m above sea level.
The cerrado is the largest vegetation type in Brazil after the Amazonian rainforest and contains open and forest savanna, grassland and patches of dense deciduous woodland. It occupies about 20% of the Brazil’s land surface (about 1.8 million km2). Originally, almost 50% of Minas Gerais state was covered by cerrado, but it is now reduced to 25%.
The FZB-BH reserve is one of the few remnant municipal areas of vegetation. This native vegetation fragment is very important as besides being a useful area for foraging, it is also indispensable to the remnant fauna for nestbuilding and shelter in an urban environment.
Research was undertaken on a 3,2 ha area inside the FZB-BH in 2000, aiming to analyse the phyto-sociology of the vegetation and carry out parallel studies on the effect of a couple of mane-wolves (Chrysocyon brachyurus) in a semi-enclosed area.
Phyto-sociological studies are extremely important for characterizing the role of each species in the community and how they contribute to the succession and to evaluate the effect of human activity on the vegetation. These studies are useful for restoration programmes and the appropriate management of protected areas.
The phyto-sociological parameters are: density, absolute and relative frequency and dominance. An index of relative values is known as the importance value (VI) and the index of density and dominance is known as the cover value (VC).
To obtain the phyto-sociological data, 8 transects measuring 3 x 50 m were distributed randomly. All specimens with a trunk circumference bigger or equal to 15 cm at chest level were sampled (CAP).
The collected data (height, CAP and botanic name) measured the floristic composition, structure and physiognomy of the vegetation, which can be shown by a phyto-physiognomy profile (Figure 1). All the collected material was prepared according to the usual herbarium rules and vouchers were deposited at the FZB–BH Botanic Garden Herbarium.
In this area, the canopy can reach 15 m high. It is not possible to distinguish clear-cut strata, since the forest is in a late successional regeneration process. The sun reaches the forest interior easily and, although there are many lianas, walking inside is relatively easy. There are some gaps with a rich understory stratum and a quantity of climbing trees.
181 specimens of 61 species belonging to 20 families were recorded. The families Myrtaceae, Rubiaceae, and Fabaceae contributed the greatest number of species. In relation to the VI (importance value), the families Fabaceae (19.76%), Caesalpiniaceae (14.59%) and Myrtaceae (10.01%) stand out. The five species with the highest VI values (38.67 % of the total of the VIs) are: Copaifera langsdorffii (12.68%), Platypodium elegans (9.93%), Bowdichia virgilioides (6.93%), Trichillia pallida (4.99%) and Casearia sylvestris (4.08%). C. sylvestris and T. pallida show a more uniform distribution in the area, although they present a VI lower than P. elegans and B. virgilioides.
A further study is being undertaken on a 5 ha site in FZB-BH in 2002, to investigate the phyto-sociology of the flora. For this on-going research, 25 transects are being used measuring 10 x 20 m. All specimens that have a trunk circumference bigger or equal to 10 cm at the soil level (CAS) have been sampled. The same phyto-sociological parameters as in the previous study will be used. This study will provide information for the future management plans of the area.