This work had as objective to investigate the effect of the size of the forest islands, of its
distances for the continuous forest (isolation) and for the adjacent roads on the coprófagos
community of Scarabaeidae. Samples had been collected in 24 islands of semideciduous
forest, between 0,5 and 360 ha, in an Amazonian savanna matrix and eight places in
predominantly secondary, semideciduous continuous forest, in the region of Alter do Chão,
Santarém, Pará. The Scarabaeidae had been collected with pitfall traps with bait (human
dung) in two seasonal periods (dries and rain). For each point of collection 10 traps had
been installed in two 250 m transects, distant 100 m between itself. 5 traps in each transect
that had been placed 50 m apart. For each place of collect was registered the DAP (Height
Brest Tree Diameter), of all trees with equal or superior diameter of the 5 cm, in four 250
transectos of 2 x m, being these used data to derive the indices from the structure of the
vegetation (average diameter and number of individuals). The area, perimeter and the
distances of the islands for the continue forest had been calculated using respectively the
extensions "X-Tools" and "Nearest Features v3.6d" for ArcView, on the map of the area
digitalized from an image of Landsat TM of 1996. The collected units had been identified
with the aid of specialized bibliography and specialists. For the characterization of the
fauna, the joined species had been compared with a list of species generated from
publications for the Cerado, Amazonia and Brazilian ecotone (cerrado-floresta). To
evaluate the robustness of the sampling, curves of rarefação had been used and gotten
estimates of wealth using itself diverse estimators. For the analysis of the standards of the
communities, an analysis HNMDS (Semi-strong Hibrid Multidimensional Scaling) using
itself in the distance of Bray-Curtis was used. 18 pertaining sorts and 36 species to biomas
of the Cerrado and Amazonia had been found, but was not possible to have a complete
notion of the parcel of each biome represented in this ecotone of transition savanna-forest,
once that the samples had not been enough for the exhausting survey of the wealth of
Scarabaeidae. The ordinance showed a trend of grouping of the continuous forests and
separation of these of the forest islands. Although the survey to have registered a bigger
number of species in the forest islands that in the areas of continuous forest, the
communities had presented a strong hierarchic standard [ P (T< 14,87°)<0,001 ], indicating
that in the islands they are persisting only one parcel of the total of species of the region. A
relation was not found enters the composition of Scarabaeidae and the size and the form of
the forest islands. But a significant relation between the composition (axle 1) and the
isolation (F=5,363, P=0,031) and the composition (axle 1) and the number of trees was
found (DAP > 5 cm) (F=6,103, P=0,012, corrected for Bonferroni). The number of trees of
each place of sampling was related with the proximity of roads (0,658), what it strengthens
the idea of that the roads are contributing for changes in the structure of the vegetation, that
in turn has a effect on the fauna of Scarabaeidae.
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