Leaf litter manipulations alter soil physicochemical properties and tree growth in a Neotropical savanna
- 426 Downloads
This study was aimed to assess the role that leaf litter play in nutrient cycling, nutrient soil availability and ecosystem processes in an oligotrophic tropical savanna.
A four year experiment was performed in a Neotropical savanna from the Brazilian plateau (cerrado), in which litter levels were modified, and the resulting changes in biophysical and chemical soil properties were studied. Changes in organic matter decomposition, soil respiration and stem growth of the six most common tree species were also monitored.
Compared to litter removal plots, double litter plots had lower maximum soil temperature and higher soil water content, and litter decomposition rates in one of three species studied, consistent with higher soil respiration rates observed in this treatment. With the exception of Ca, there were no significant differences in nutrients between the removal, natural and double litter plots, even though most nutrients tended to increase in the double litter plots by the end of the experimental period, while in the control plots nutrient levels remained relatively constant. Of the six tree species used for growth analysis, only one, Sclerolobium paniculatum, a fast growing species with shallow roots, had a significant increase in stem growth due to litter addition.
Preliminary results over four years indicate that litter removal and addition resulted in some significant changes and tendencies that indicate that litter is effectively altering ecosystem processes. The information obtained also suggest that nutrient cycling in plots with natural litter levels (control plots) was in a closed loop; most nutrients released by litter decomposition and mineralization were absorbed and reutilized immediately by the plants, thus minimizing nutrient leakage outside the system.
KeywordsLitter decomposition rates Nutrient cycling Soil fertility Soil respiration Tree growth Tropical savannas
We thank the Reserva Ecologica do IBGE for logistic support. We are very grateful to Catarina S. Cartaxo, Ana Salazar Parra, Sybil G. Gotsch, Cristiane Ferreira and Lucas Silva for invaluable assistance with fieldwork. Heloisa S. Miranda and Vania R. Pivello provided excellent comments on the manuscript. This research was supported by NSF Biocomplexity Grant EAR 0322051 and CNPQ, Brazil.
- Allen SE (1989) Chemical analysis of ecological materials, 2nd edn. Blackwell Scientific, OxfordGoogle Scholar
- Anderson JPE, Domsch KH (1978) A physiological method for quantitative measurement of microbial biomass in soils. Soil Biol Biochem 29:1133–1142Google Scholar
- Cattelino PJ, Becker CA, Fuller LG (1986) Construction and installation of nomemade dendrometer bands. North J Appl For 3:73–75Google Scholar
- Franco AA, Campello EFC, Dias LE, De Faria SM (1996) Uso de leguminosas associadas a microrganismos na revegetação de áreas de mineração de bauxita em Porto Trombetas-Pa. Serie Documentos(27), EMBRAPA-CNPAB, Itaguaí. 71ppGoogle Scholar
- Franco AC, Bustamante M, Caldas LS, Goldstein G, Meinzer FC, Kozovits AR, Rundel P, Coradin VTR (2005) Leaf functional traits of Neotropical savanna trees in relation to seasonal water deficit. Trees Struct Funct 19(3):326–335Google Scholar
- Furley PA (1999) The nature and diversity of Neotropical savanna vegetation with particular reference to the Brazilian cerrados. Glob Ecol Biogeogr 8:223–241Google Scholar
- Garofalo CR (2001) Efeitos do aumento da disponibilidade de nutrients na dinámica de nutrientes en plantas herbáceas e solo em uma área de cerrado stricto sensu. Brazil. University of Brasilia. M.S. thesisGoogle Scholar
- Gibbs PE, Leitao HD, Shepherd G (1983) Floristic composition and community structure in an area of cerrado in SE Brazil. Flora 173:433–449Google Scholar
- Haridasan M (1992) Observations on soils, foliar nutrient concentrations, and floristic composition of cerrado and cerradão communities in central Brazil. In: Proctor J, Ratter JA, Furley PA (eds) The nature and dynamics of forest-savanna boundaries. Chapman and Hall, London, pp 171–184Google Scholar
- Haridasan M (2000) Nutrição mineral de plantas nativas do cerrado. Braz J Plant Physiol 12:54–64Google Scholar
- Haridasan M (2001) Nutrient cycling as a function of landscape and biotic characteristics in the cerrado of central Brazil. In: McClain ME, Victoria RL, Richey JE (eds) Biogeochemistry of the Amazon basin and its role in a changing world. Oxford University Press, New York, pp 68–83Google Scholar
- IBGE (1995) Zoneamento ambiental do Córrego Taquara-DF. Volumes I a IV. IBGE, GoiâniaGoogle Scholar
- Peng SL, Ren H, Wu JG, Lu HF (2003) Effects of litter removal on plant species diversity: a case study in tropical eucalyptus forest ecosystems in South China. J Environ Sci 15:367–371Google Scholar
- Ponge JF, Arpin P, Vannier G (1993) Collembolan response to experimental perturbations of litter supply in a temperate forest ecosystem. Eur J Soil Biol 29:141–153Google Scholar
- Poser T (1990) The influence of litter manipulation on the centipedes of a beech wood. In: Minelli A (ed) Proceedings of the seventh international congress on Myriapods. Brill, Leiden, pp 235–245Google Scholar
- Quintanilha de Albuquerque E, Dias LE (1999) Decomposição de folhas de Acacia mangium e Sclerobium paniculatum (tachi-branco) em colunas de solo. Revista Árvore 23:15–22Google Scholar
- R Development Core Team (2008) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL http://www.R-project.org
- Ribeiro JF (1983) Comparação da concentração de nutrientes da vegetação arbórea e nos solos de um cerrado e um cerradão no Distrito Federal, Brasil. MSc Thesis, University of Brasília, BrazilGoogle Scholar