, Volume 11, Issue 8, pp 1234-1246

First online:

Understanding the Influences of Spatial Patterns on N Availability Within the Brazilian Amazon Forest

  • Gabriela Bielefeld NardotoAffiliated withCentro de Energia Nuclear na Agricultura, Universidade de São Paulo Email author 
  • , Jean Pierre Henry Balbaud OmettoAffiliated withCentro de Energia Nuclear na Agricultura, Universidade de São Paulo
  • , James R. EhleringerAffiliated withSIRFER, Biology Department, University of Utah
  • , Niro HiguchiAffiliated withInstituto Nacional de Pesquisas da Amazônia
  • , Mercedes Maria da Cunha BustamanteAffiliated withDepartamento de Ecologia, Universidade de Brasília
  • , Luiz Antonio MartinelliAffiliated withCentro de Energia Nuclear na Agricultura, Universidade de São Paulo

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


Nitrogen variations at different spatial scales and integrated across functional groups were addressed for lowland tropical forests in the Brazilian Amazon as follows: (1) how does N availability vary across the region over different spatial scales (regional × landscape scale); (2) how are these variations in N availability integrated across plant functional groups (legume × non-legume trees). Leaf N, P, and Ca concentrations as well the leaf N isotope ratios (δ15N) from a large set of legume and non-legume tree species were measured. Legumes had higher foliar N/Ca ratios than non-legumes, consistent with the high energetic costs in plant growth associated with higher foliar P/Ca ratios found in legumes than in non-legumes. At the regional level, foliar δ15N decreased with increasing rainfall. At the landscape level, N availability was higher in the forests on clayey soils on the plateau than in forests on sandier soils. The isotope as well as the non-isotope data relationships here documented, explain to a large extent the variation in δ15N signatures across gradients of rainfall and soil. Although at the regional level, the precipitation regime is a major determinant of differences in N availability, at the landscape level, under the same precipitation regime, soil type seems to be a major factor influencing the availability of N in the Brazilian Amazon forest.


nitrogen lowland tropical forest nitrogen stable isotopes Amazonia foliar phosphorus terra-firme forest campinarana forest