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ABSTRACT. Fire is a major determinant of structure and dynamics in savannas, and the rapid increase of human activities in this biome has changed the natural burning regime. The effects of fire on the fauna of the cerrado (Brazilian savanna) are still poorly understood, and studies comparing sites frequently and infrequently burned are scarce. In this study, the abundance of epigaeic arthropod orders and trophic guilds was assessed in cerrado sites located in the Brazilian Central Plateau that were subjected to three burning frequencies: frequent (HighFi), intermediary (MidFi), and infrequent (LowFi).In general, we found a positive relationship between the abundance of epigaeic arthropods and fire frequency. When arthropods were analyzed by orders, the abundance of Collembola and Orthoptera was lower in the LowFi site, while for Hemiptera, it was higher in the MidFi site. No significant differences were found for Hymenoptera, Coleoptera, and Araneae.The abundance of detritivores and herbivores decreased from HighFi to LowFi, but did not change significantly for omnivores and predators. These results indicate that some arthropod groups may not only be resilient to fire effects, but actually might benefit from fire effects in the cerrado. Characterizing arthropod responses to burning frequency at high taxonomic or functional levels is important for applied studies. Based on the results of the current study, springtails and ants seem to be particularly appropriate focal groups for further exploratory studies on the effects of fire at the species level.

-The objective of this work was to evaluate the effect of organic and conventional coffee crops on biomass, population density and diversity of earthworms, in Lerroville, district of Londrina County, Paraná state, Brazil. Earthworm communities were sampled in three areas with organic coffee cultivation (CO1, CO2 and CO3), two with conventional coffee (CC1 and CC2), and a native forest fragment (MT). The soil of the areas CO1, CC1, and MT was classifi ed as Nitossolo Vermelho (Rhodic Kandiudox), while CO2, CO3, and CC2 were on Latossolo Vermelho (Rhodic Hapludox). Eight samples were taken in each area on two occasions, winter and summer, using the Tropical Soil Biology and Fertility (TSBF) method in the 0-20 cm soil layer. The earthworms were handsorted and preserved in 4% formaldehyde, and were later weighed, counted and identifi ed. The highest earthworm biomass, both in winter and summer, occurred in the CO3 area. For population density, the higher numbers of individuals were found in CO1 and CO3. The highest number of species was identifi ed in the organic cultivation. The adoption of organic practices in coffee cultivation favored the diversity, density and biomass of earthworm communities.Index terms: biomass, conventional cultivation, diversity, Oligochaeta, organic cultivation, population density. Comunidades de minhocas em cultivo de café orgânico e convencionalResumo -O objetivo deste trabalho foi avaliar o efeito do cultivo de café orgânico e convencional sobre a biomassa, densidade populacional e diversidade de minhocas em Lerroville, distrito de Londrina, Paraná. A comunidade de minhocas foi avaliada em três áreas de cultivo orgânico (CO1, CO2, CO3), duas áreas em cultivo convencional (CC1 e CC2) e um fragmento de mata nativa (MT). O solo das áreas CO1, CC1 e MT foi classifi cado como Nitossolo Vermelho e o solo das áreas CO2, CO3 e CC2 como Latossolo Vermelho. Oito amostras foram coletadas em cada área, em dois períodos, inverno e verão, pelo método do Tropical Soil Biology and Fertility (TSBF), na camada 0-20 cm. As minhocas foram separadas manualmente e preservadas em formol 4%, e, depois, foram pesadas, contadas e identifi cadas. A biomassa das minhocas, nas amostragens de inverno e de verão, foi maior na área CO3. A densidade populacional foi maior nas áreas CO1 e CO3. O maior número de espécies foi identifi cado nos cultivos orgânicos. A adoção de práticas orgânicas, no cultivo do café, favoreceu a diversidade, densidade populacional e biomassa das comunidades de minhocas.Termos para indexação: biomassa, cultivo convencional, diversidade, Oligochaeta, cultivo orgânico, densidade populacional.