03964naa a2200169 a 450000100080000000500110000800800410001910000230006024501310008326000090021452031740022370000220339770000190341970000180343870000170345677303210347313150822008-10-07       2008    bl uuuu     u00u1 u    #d1 aTAPIA-CORAL, S. C.  aSoil macrofauna community in mulched and non-mulched secondary forest of the Tarumã-Mirim rural settlement, Amazonas, Brazil.  c2008  aDeforestation and conversion of forest into farmland, traditionally by slash-and-burn clearing, is harmful to the soil fauna, which is sensitive to human impact as well as to inherent characteristics of the particular ecosystem, such as climate, soil and vegetation. We estimated the soil macrofauna community in mulched and non-mulched secondary forest of different age groups in small farms of the Tarumã-Mirim rural settlement, located 30 km north of Manaus, Amazonas. The secondary forest biomass was cut and chopped (September 2006) by a ?Tritucap? tractor used as an alternative to fire for smallholders. Samples were collected in three secondary forest of different age groups: 2, 5 and 10 years (mulched secondary forest) and in three control secondary forest of the same age groups (non-mulched) at the beginning of the rainy season (December 2005, precipitation: 322 mm) and during the rainy season (March 2006, precipitation: 377 mm). The soil macrofauna was sampled applying a modified TSBF (Tropical Soil Biology and Fertility) method, by randomly collecting five 50x50x20cm deep soil blocks along a 50 m transect in each system. Predominant factors of soil macrofauna density in different mulched and control pastures were obtained by Principal Component Analysis (PCA) using the ADE4 program. The predominant taxonomic soil macrofauna groups in the control and secondary forest were Formicidae, Oligochaeta, Isoptera, and Isopoda. At the beginning of the rainy season, the PCA explained 57.1 % of the total variance. Factor 1 explained 39.9 %, correlating the communities of Aranea, Blattaria, Coleoptera, Diplopoda, Formicidae, and Opilon and factor 2 (17.2 %) correlating the communities of Scorpions, Pseudoscorpions, and Uropyge. During the rainy season, the PCA explained 53.3 % of the total variance, factor 1 (33 %) correlating the communities of Diplopoda, Formicidae, Isopoda, Opilon, and Thysanoptera and factor 2 (20.3 %) correlating the communities of Scorpions, Hymenoptera, and Uropyge. In the early rainy season, the 2-year-old control and secondary forest showed similar total soil macrofauna densities of 379 ind.m-² and 388 ind.m-², respectively, while during the rainy season, the variance in secondary forest decreased to 231 ind.m-². This is probably due to the low subsoil density in the 2-year-old secondary forest (personal observation), which after the chopping treatment got exposed to sun and rain. The 5-year-old secondary forest showed a higher internal variation, and soil macrofauna density in control secondary forest was higher (311 ind.m-²) than that of mulched secondary forest. Although the differently aged non-mulched secondary forest showed higher soil-macrofauna densities than the secondary forest, the densities in the 5- and 10-year-old secondary forest were higher than that in the 2-year-old secondary forest during the rainy season. The project was financed by the Fundação de Amparo a Pesquisa do Estado do Amazonas ? FAPEAM, Instituto Nacional de Pesquisas da Amazônia, Coordenação de Pesquisas em Entomologia - INPA/CPEN and Large scale Biosphere Atmosphere Experiment in Amazonia (LBA) Program.1 aLINS-TEIXEIRA, A.1 aLUIZÃO, F. J.1 aMORAIS, J. W.1 aWANDELLI, E.  tIn: INTERNATIONAL COLLOQUIUM ON SOIL ZOOLOGY, 15; INTERNATIONAL COLLOQUIUM ON APTERYGOTA, 12., 2008, Curitiba. Biodiversity, conservation and sustainabele management of soil animal: abstracts. Colombo: Embrapa Florestas. Editors: George Gardner Brown; Klaus Dieter Sautter; Renato Marques; Amarildo Pasini. 1 CD-ROM.