02680naa a2200145 a 450000100080000000500110000800800410001910000210006024501050008126000090018652019820019570000170217770000190219477303210221313150042008-10-02       2008    bl uuuu     u00u1 u    #d1 aSANTOS, E. M. R.  aLitter manipulation and associated invertebrate fauna in secondary forest, central Amazonia, Brazil.  c2008  aPlant litter from selected tree species have been used for improving soil productivity in low-input systems of secondary vegetation in central Amazon, leading to different conditions for the soil organisms. Soil animal assemblages were monitored to test the effects of adding litter types of contrasting nutritional quality, and periods of exposure on the development of the invertebrate community. We established four second growth plots with 80 subplots of 3 m2 from which the original litter was removed and replaced in 60 subplots. Twenty subplots received Hevea brasiliensis leaves, 20 others Carapa guianensis leaves, and another 20 an equal mixture of H. brasiliensis, C. guianensis and Vismia guianensis. Twenty subplots were left with the original litter. Litter and mineral soil (5 cm deep) sub-horizons were collected after 45, 100, 160, 240 and 300 days of exposure. The invertebrates were extracted using Kempson apparatus. At the day 210th, the litter was replenished to match the surrounding litter. Regression analyses showed no significant effect of litter type, but the period of exposure did affect the community in both subhorizons. Only after the litter replacement, the type of litter and periods of exposure affected the community in the litter sub-horizon. Because we tried to isolate the effects of litter composition from other large-scale phenomena, several factors interfered in the experiment and potential problems were identified to optimize the investigation. The results suggest that the sampling design must be improved by using a larger number of subsamples for each kind of litter within each plot. As the scale of the experiments was too small, future manipulations should be done on much larger scale so that their effects on ecosystem processes can be evaluated, and the replicates need to be spread over larger areas to capture the natural variations within ecosystems. Financial support: SHIFT/ENV 052, CNPq/PNOPG: 55 04 09/01-7, CAPES.1 aFRANKLIN, E.1 aLUIZÃO, F. J.  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.