RT Journal Article
T1 Spatialized N budgets in a large agricultural Mediterranean watershed: high loading and low transfer
A1 Lassaletta Coto, Luis
A1 Romero, Estela
A1 Billen, G.
A1 Garnier, J.
A1 García-Gómez, H.
A1 Rovira Sanroque, José Vicente
AB Despite the particular management practices and climate characteristics of the Mediterranean regions, the literature dealing with N budgets in large catchments subjected to Mediterranean conditions is scarce. The present study aims to deepen our knowledge on the N cycle within the Ebro River Basin (NE Spain) by means of two different approaches: (1) calculating a global N budget in the Ebro River Basin and (2) calculating a series of detailed regional budgets at higher geographical resolution. N inputs and outputs were spatialized by creating a map based on the most detailed information available. Fluvial and atmospheric N export was estimated together with N retention. The Ebro River Basin annually receives a relatively high amount of new N (5118 kgNkm−2 yr−1), mostly in the form of synthetic fertilizers (50 %). Although it is a highly productive catchment, the net N input as food and feed import is also high (33 %). Only 8% of this N is finally exported to the delta zone. Several territorial units characterized by different predominant uses (rainfed agriculture, irrigated agriculture and pastures) have differentiated N dynamics. However, due to the high density of irrigation channels and reservoirs that characterize Mediterranean basins, N retention is very high in all of them (median value, 92 %). These results indicate that problems of eutrophication due to N delivery in the coastal area may not be too severe but that high N retention values may instead lead to problems within the catchment, such as pollution of aquifers and rivers, as well as high atmospheric emissions. The most promising management measures are those devoted to reducing agricultural surpluses such as balanced N fertilization and low N livestock feeding.
PB European Geosciences Union (EGU)
SN 1810-6285
YR 2011
FD 2011
LK https://hdl.handle.net/20.500.14352/42917
UL https://hdl.handle.net/20.500.14352/42917
LA eng
NO Ministerio de Medio Ambiente, y Medio Rural y Marino (MARM)
NO Universidad Complutense de Madrid
NO Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)
NO Federation Ile-de-France for Research on the Environment (FIRE)
NO Centre National de la Recherche Scientifique (CNRS)
DS Docta Complutense
RD 7 jun 2025