LITTER DECOMPOSITION IN SEMIDECIDUOUS FOREST AND EUCALYPTUS SPP CROP IN BRAZIL - A COMPARISON

The litter decomposition in Eucalyptus crop was compared with that in a semidecidous forest using four treatments: FF, forest litter in fore st; EE, Eucalyptus litter in Eucalyptus; FE, forest litter in Eucalypt us; EF, Eucalyptus litter in forest. The nutrient status of each treat ment and the abundance of Acari and Collembola in FF and EE were estim ated. FF presented a higher decay rate (c = - 0.00360 g day(-1)) compa red with EE (c = - 0.00241 g day(-1)) and FE (c = - 0.00302 g day(-1)) , but the FF rate was close to that of EF (c = - 0.00319 g day(-1)). A greater heterogeneity was observed around the fitted regression in th e forest litter (FF and FE), suggesting a higher variability in leaf q uality. Acari and Collembola were more abundant in FF than in EE. The better litter and microhabitat conditions may account for these differ ences. The effects of litter source and decomposition site on nutrient concentration were tested using a two-way analysis of variance. Regar ding the source, a significant effect was found on all nutrients analy sed (N, Mg, Ca, P), but the site effect was observed only on Mg, Ca an d P. The results are discussed in terms of the possible implications r egarding the culture of exotic plants in tropical landscapes. (C) 1997 Elsevier Science B.V.