author = "Bustamante, Mercedes M. C. and Martinelli, Luiz Antonio and 
                         P{\'e}rez, Tibisay and Rasse, Rafael and Ometto, Jean Pierre 
                         Henry Balbaud and Pacheco, Felipe Siqueira and Lins, Silvia 
                         Rafaela Machado and Marquina, Sorena",
          affiliation = "{Universidade de Bras{\'{\i}}lia (UNB)} and {Universidade de 
                         S{\~a}o Paulo (USP)} and {Instituto Venezolano de Investigaciones 
                         Cient{\'{\i}}ficas (IVIC)} and {Instituto Venezolano de 
                         Investigaciones Cient{\'{\i}}ficas (IVIC)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Universidade de S{\~a}o Paulo 
                         (USP)} and {Instituto Venezolano de Investigaciones 
                         Cient{\'{\i}}ficas (IVIC)}",
                title = "Nitrogen management challenges in major watersheds of South 
              journal = "Environmental Research Letters",
                 year = "2015",
               volume = "10",
               number = "6",
                pages = "Article number 065007",
                month = "June",
             keywords = "agriculture, nutrient management, wastewater.",
             abstract = "Urbanization and land use changes alter the nitrogen (N) cycle, 
                         with critical consequences for continental freshwater resources, 
                         coastal zones, and human health. Sewage and poor watershed 
                         management lead to impoverishment of inland water resources and 
                         degradation of coastal zones. Here we review the N contents of 
                         rivers of the three most important watersheds in South America: 
                         the Amazon, La Plata, and Orinoco basins. To evaluate potential 
                         impacts on coastal zones, we also present data on small- and 
                         medium-sized Venezuelan watersheds that drain into the Caribbean 
                         Sea and are impacted by anthropogenic activities. Median 
                         concentrations of total dissolved nitrogen (TDN) were 325 
                         \μg L-1 and 275 \μg L-1 in the Amazon and Orinoco 
                         basins, respectively, increasing to nearly 850 \μg L-1 in La 
                         Plata Basin rivers and 2000 \μg L-1 in small northern 
                         Venezuelan watersheds. The median TDN yield of Amazon Basin rivers 
                         (approximately 4 kg ha-1 yr-1) was larger than TDN yields of 
                         undisturbed rivers of the La Plata and Orinoco basins; however, 
                         TDN yields of polluted rivers were much higher than those of the 
                         Amazon and Orinoco rivers. Organic matter loads from natural and 
                         anthropogenic sources in rivers of South America strongly 
                         influence the N dynamics of this region.",
                  doi = "10.1088/1748-9326/10/6/065007",
                  url = "http://dx.doi.org/10.1088/1748-9326/10/6/065007",
                 issn = "1748-9326",
             language = "en",
           targetfile = "Bustamante_nitrogen.pdf",
        urlaccessdate = "05 dez. 2020"