Mutema M. auteur aut IRD Chaplot Vincent auteur aut IRD Jewitt G. auteur aut IRD Chivenge P. auteur aut IRD Bloschl G. auteur aut IRD text journalArticle eng text/pdf born digital access Process controls on water, sediment, nutrient, and organic carbon exports from the landscape through runoff are not fully understood. This paper provides analyses from 446 sites worldwide to evaluate the impact of environmental factors (MAP and MAT: mean annual precipitation and temperature; CLAY and BD: soil clay content and bulk density; S: slope gradient; LU: land use) on annual exports (RC: runoff coefficients; SL: sediment loads; TOCL: organic carbon losses; TNL: nitrogen losses; TPL: phosphorus losses) from different spatial scales. R-C was found to increase, on average, from 18% at local scale (in headwaters), 25% at microcatchment and subcatchment scale (midreaches) to 41% at catchment scale (lower reaches of river basins) in response to multiple factors. SL increased from microplots (468 g m(-2) yr(-1)) to plots (901 g m(-2) yr(-1)), accompanied by decreasing TOCL and TNL. Climate was a major control masking the effects of other factors. For example, R-C, SL, TOCL, TNL, and TPL tended to increase with MAP at all spatial scales. These variables, however, decreased with MAT. The impact of CLAY, BD, LU, and S on erosion variables was largely confined to the hillslope scale, where R-C, SL, and TOCL decreased with CLAY, while TNL and TPL increased. The results contribute to better understanding of water, nutrient, and carbon cycles in terrestrial ecosystems and should inform river basin modeling and ecosystem management. The important role of spatial climate variability points to a need for comparative research in specific environments at nested spatiotemporal scales. specialized MONDE 062 51 11 8949-8972 2015 0043-1397 https://www.documentation.ird.fr/hor/fdi:010066142 10.1002/2014wr016668 0043-1397 [F B010066142] https://www.documentation.ird.fr/hor/fdi:010066142 https://www.documentation.ird.fr/intranet/publi/2016/02/010066142.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2016-02-26 2017-08-23 fdi:010066142 fre