Estudo da ocorrência e estado de conservação da Raphia australis Oberm. Strey na Reserva Botânica de Bobole

Abstract

The present project was carried out in the Bobole Botanical Reserve (RBB) with the aim of knowing the current conservation status of the species of Raphia australis. This species is quasi-endemic in Mozambique and lives associated with different forms of flora and fauna, constituting habitat, food and nutrient cycling for various epiphytes, ferns, microfauna and other living beings. R.australis is under extreme threat, due to being located in an area with a great agricultural potential, attracting the surrounding communities to overthrow it for the practice of agriculture. The RBB was created in 1945 with an area of ​​200 ha, the destruction of this forest was initiated by itinerant farmers, who started to cut it down to carry out on the place where it was implanted, subsistence crops. Subsequently, business agriculture, namely banana and rice, accelerated the destruction of the forest. RBB currently has only 12 ha of area. In order to achieve the objective of this work, a mapping of R. australis spots in its area of ​​occurrence was made within the RBB, using the following instruments: GPS, Computer with Arcgis 9.3 software, aerial photographs of the RBB on a scale of 1: 5000, topographical chart of the RBB in the scale 1: 5000. A survey of seed abundance, natural regeneration, non-fruited adults and fruited adults was also carried out, in which a total of 13 transects were established. Each transect was made up of 30 10 x 10 m (100 m2) squares. This methodology was adopted with the aim of comparing the results of this study with that of Sambane (1999). Regarding the analysis of the conservation status of R. australis, the factors that influence the survival of the species were described, namely: biophysical conditions of the place, humidity and soil organic matter content, and the current status of the reserve was characterized; using the following instruments: soil survey probe and 8 pF rings with a volume of 100 cm3. The average humidity was 45% and the average organic matter content was 5.68%, both factors presented enormous amplitudes. The coverage of R.australis patches occupied an area of ​​0.44 ha equivalent to 4% of the total area of ​​the reserve, the remaining 96% are occupied by plots of agriculture, native and exotic vegetation and grass.(TRADUÇÃO NOSSA)