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 T...

The size of the bioavailable (i.e., “fixed”) nitrogen inventory in the ocean influences global marine productivity and the biological carbon pump. Despite its importance, the pre-industrial rates for the major source and sink terms of the oceanic fixed nitrogen budget, N2 fixation and denitrification, respectively, are not well known. These processes leave distinguishable imprints on the ratio ...

Introduction Conclusions References

We present in this study both measurement-based and modeling analyses for elucidation of source attribution, influence areas, and process budget of reactive nitrogen oxides at two rural southeast United States sites (Great Smoky Mountains national park (GRSM) and Mammoth Cave national park (MACA)). Availability of nitrogen oxides is considered as the limiting factor to ozone production in these...

[1] Recent advances in ecosystem descriptions associated with nitrogen (N) saturated forests allowed us to revise and improve a model of ecosystem productivity to reflect advanced N saturation. We introduce a new description of nitrogen cycling for a forest that is in stage 2 of N saturation on the basis of recent literature. We compared the accuracy of this new description to the conventional ...