ISSN: 2639-216X
Authors: Tubelis DP*
Although studies of edge effects have great importance for reserve design, they have rarely investigated impacts into nature reserves. This study aimed to examine edge effects associated with adjacent agricultural landscape on birds at Parque Nacional das Emas, Brazil. Study sites [n = 36] were plots in the natural grassland habitat located at four distance bands in relation to the boundary line between protected vegetation and agricultural fields [0-500 m, 500-1,000 m, 1,000-1,500 m and interior]. Birds were surveyed through transect counts between October 2006 and February 2007. GLMMs were used to analyse variation in the abundance of selected species and trophic guilds among distance intervals, while species richness was compared through curves of rarefaction. Variation in community composition was evaluated through Correspondence Analysis. A total of 59 species were recorded. Species more sensitive to proximity to agriculture were insectivores such as Culicivora caudacuta and Alectrurus tricolor. Granivores and omnivores were more abundant close to rather than distant from agriculture. The species richness of the whole community and that of guilds did not vary among distance intervals, as result of species replacement. Communities found in the 0-500 m and 500-1,000 m intervals were very distinct from those of the interior. Edge effects penetrated up to 1,500 m into the park, being more intense within 1 km from adjacent modified landscapes. This study suggests that more effort should be done to establish effective buffer zones [> 1.5 km in width] and avoid the settlement of agribusiness adjacent to nature reserves in Cerrado.
Keywords: Agribusiness; Biodiversity; Boundary; Edge Effects; Landscape Matrix; Savanna
