The available information on organic carbon-, nitrogen- and phosphorus export by Latin-American catchments is compiled, also including data on wet atmospheric deposition. TOC export ranges 21.00-126 kg C/ha/year, whereas DOC export amounts to 14.92-764.67 kg C/ha/year. TN flux and nitrate export were 0.50 - 46.67 kg N/ha/year and 0.001-16.57 kg N/ha/year, respectively. Wet deposition of nitrate ranges 1.50-14.21 kg N/ha/year. TP flux varies between 0.04 and 4.50 kg P/ha/year, whereas that of SRP ranges 0.002-3.17 kg P/ha/year. Control variables of nutrient export in Latin-American catchments are mostly of climatic nature (rainfall, runoff) and explain a high fraction of overall variability (31-86%), but also inhabitant density and the pastureland percentage of catchment area are important for nitrogen variability. No relationship between environmental variates and phosphorus export has been found, perhaps because only little degraded watersheds have been studied so far. Nitrogen and phosphorus export variability appears to be wider in catchments of Canada and USA which also suffer from a wider range of anthropogenic stress. Generally, nutrient export research in Latin-American catchments has been carried out in more or less pristine watersheds and by non local scientists. Future local research agendas should engage in comparative studies of pristine and degraded catchments to better understand the biogeochemical role of fluvial ecosystems in Latin America.

14 páginas y tablas estadísticas.

Peer reviewed