SciELO - Scientific Electronic Library Online

 
vol.72 issue3  suppl.The southern Brazilian grassland biome: soil carbon stocks, fluxes of greenhouse gases and some options for mitigationNitrogen cycle and ecosystem services in the Brazilian La Plata Basin: anthropogenic influence and climate change author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Brazilian Journal of Biology

Print version ISSN 1519-6984

Abstract

MARTINELLI, LA et al. Nitrogen mass balance in the Brazilian Amazon: an update. Braz. J. Biol. [online]. 2012, vol.72, n.3, suppl., pp.683-690. ISSN 1519-6984.  http://dx.doi.org/10.1590/S1519-69842012000400007.

The main purpose of this study is to perform a nitrogen budget survey for the entire Brazilian Amazon region. The main inputs of nitrogen to the region are biological nitrogen fixation occurring in tropical forests (7.7 Tg.yr-1), and biological nitrogen fixation in agricultural lands mainly due to the cultivation of a large area with soybean, which is an important nitrogen-fixing crop (1.68 Tg.yr-1). The input due to the use of N fertilizers (0.48 Tg.yr-1) is still incipient compared to the other two inputs mentioned above. The major output flux is the riverine flux, equal to 2.80 Tg.yr-1 and export related to foodstuff, mainly the transport of soybean and beef to other parts of the country. The continuous population growth and high rate of urbanization may pose new threats to the nitrogen cycle of the region through the burning of fossil fuel and dumping of raw domestic sewage in rivers and streams of the region.

Keywords : nitrogen balance; Amazon; biological nitrogen fixation; land use changes; urbanization.

        · abstract in Portuguese     · text in English     · English ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License