Invertebrados de cavernas do Distrito Federal: diversidade, distribuição temporal e espacial

Franciane Jordão da Silva

There are 4,153 registered caves in Brazil, but most cave studies has been done by observant cavers rather than part of surveying programs. A correlate problem is the lack of ertebrates were sampled by active seach (hand collecting and the register of rganisms) and by baited pitfall traps. The number of traps varied among caves due to their morphological and size differences. The pitfall traps remained actives during three consecutive days and the active search varied from two to four/hours/day on each collection month. The Labirinto da Lama cave was inundated in February 2004 but some organisms like crickets, cockroaches, springtails, flies, moths, Ctenidae spiders, and E. aduncus havestmen were not affected by this event maybe because of their agility to escape or to find protection in drier sites. The abundance of other groups decreased such as one species of Trichorhina sp. (Oniscidea) isopods, Spelaeochernes sp. (Chenertidae) pseudoscorpions, and the Carabidae beetles which were invariably associated to bat guano. Maybe these organisms have been washed away with their foods sources. The mean of invertebrate abudance and morphospecies richness were higher in the Morcegos cave than in the others, during both wet and dry months. The differences observed among them may be due to its geomorphologic and biotic characteristics besides some natural events and anthropic activities which could have affected the invertebrate taxonomists for the most invertebrate cave species. The knowledge of the Brasília cave invertebrate fauna is very poor and this work is the first one to present an ecological approach and a systematic sampling in that region. Data presented in this work will also alow comparisions among caves of different regions of the country. The present study was carried out in three caves of Brasília, Distrito Federal, within the limits of Cafuringa protected area (Área de Proteção Ambiental de Cafuringa, 1530 e 1540 S e 47 50 e 48 12 W). Two caves Sal/Fenda II and Labirinto da Lama are located at the Santa Sara and Portal dos Angicos farms respectively, in the Brazlândia, DF, and the morcegos cave is located at the mining área of Tocantins portland cement plant, in Fercal county, DF. This thesis is organized in three chapters. The first analyses the temporal and spatial distribution of invertebrates of Labirinto da Lama cave during 13 months; the second compares the invertebrates of the three caves and the last one compares the efficiency of sampling techniques. The invertebrate cave communities. Most of cave i represented only by one or two specimens whereas few species are abundant. The canonic correlation analysis showed that variables like temperature, relative air humidity, distance from cave entrance and the availability of bat guano pile were significantly correlated with the most abundant invertebrates. The sequence of importance of the above variables was different among caves. Some invertebrates were positively correlated with the availability of bat guano pile as, for distance, the Eupoecilaema megaypsilon (Cosmetidae) and Eusarcus aduncus (Gonyleptidae) havestmen, the Loxosceles similis (Sicariidae) spiders, the Histeridae beetles, and the Drosophilidae flies, while others were more abundant around the cave entrance like the spiders Enoploctenus cyclothorax (Ctenidae), Pholcidae and Araneidae, or were more affected by air humidity like the coockroaches (Blattidae). To obtain significant and consistent sample of cave invertebrate community is necessary to combine at least two different sampling techniques. The proposition is to uniform the sampling techniques for invertebrate survey works in order to allow data comparison. Such comparison will have a significant role in cave protection and its management.

Invertebrados de cavernas do Distrito Federal: diversidade, distribuição temporal e espacial

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