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Copyright of Journal of Ornithology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carbon and nitrogen stable isotopes were used to track major dietary variations in arthropods found in a cave located in a neotropical savanna in Central Brazil. We determined the δ13 C and δ15 N for cave crickets, cockroaches, spiders, guano of a hematophagous bat, and leaf litter found on the ground near the cave entrance. The δ13 C and δ15 N for the cricket and cockroaches showed that bat guano was not the only food item for these arthropods. They had intermediate δ13 C and δ15 N between bat guano and leaf litter, which means that they consumed additional food resources other than guano in their diet, independent of distribution of guano deposits in the cave. The spiders, predators with great mobility, seemed to not have a preferential diet item since their isotope signals indicated they hunt both crickets and cockroaches. The δ13 C of the bat guano (−15.4‰) indicated that the diet of these hematophagous bats relied on animals fed with C4 plants. The conversion of native savanna vegetation of which the debris is mostly from C3 plants, to pasture, based on C4 African grass, a remarkably common land use transformation in the region, is indirectly influencing the diet of hematophagous bats, which basically relied on exotic fauna. The C and N stable isotope ratios showed that the arthropods inside the cave do not rely solely on bat guano for their diet, but interact directly with the external environment, through litter debris, indicating a significant exchange of energy and matter between the cave environment and the surrounding area. [ABSTRACT FROM AUTHOR]

Stable carbon isotope ratios (δ 13C) of soil record information regarding C 3 and C 4 plants at the landscape scale that can be used to document vegetation distribution patterns. The Central Brazilian savanna (locally called the Cerrado) has a substantial potential to develop studies of patterns of dynamics and distribution of soil δ 13C, due to its environmental diversity. The purpose of this work was to develop a spatial model of soil δ 13C (soil δ 13C isoscape) to the Cerrado, based on multiple linear regression analysis, and compare the results with the existing model to obtain greater detail of the soil δ 13C distribution. The model used 219 soil samples (0–20 cm depth) and a set of climatic, pedological, topographic, and vegetation correlations. The soil δ 13C isoscape model presented amplitude between −29‰ and −13‰, with the highest estimated values in the southern and the lowest values in the northern of the Cerrado. Results indicate that soil δ 13C, by reflecting the relative contribution of C 3 and C 4 species to plant community productivity, served as a proxy indicator of the vegetation history at the landscape scale for the Central Brazilian savanna. Despite the large sampling effort, there are still regions with some gaps that the model could not estimate. However, the soil δ 13C isoscape model filled most the existing gaps and provided greater detail of some unique local aspects of the Cerrado. • Climatic, topographic, soil and vegetation aspects explain the soil δ 13C isoscape. • Modeled soil δ 13C values decrease from south to north. • Modeled soil δ 13C provided greater detail for the local aspects of the Cerrado. [ABSTRACT FROM AUTHOR]