Spatial evolution of nitrogen and phosphorus loads along a small Mediterranean river: implication of bed sediments

This study addresses the spatial variations in water quality along the River Vene (France). The Vene drains a 67 km2 rural basin, with a large karstic area, located in a Mediterranean context. A 1 day sampling campaign was conducted along the river, in winter low-flow conditions (February 2003). Physico-chemical parameters and water flow discharge were measured in situ during the sampling campaign. Water quality was evaluated by determining the concentrations of nitrogen and phosphorus in water and bed-sediment samples. Nitrogen and phosphorus loads were evaluated taking into account the measured concentrations and discharge. The campaign included 18 sampling points and concerned the whole river from the spring to the outlet, plus the main inputs, i.e. sewage treatment works, main tributaries and karstic springs. The spatial evolution of nitrogen and phosphorus loads along the river allowed the significant role of point-source inputs to be demonstrated. The decrease in nutrient loads along the river occurred mainly in specific reaches where fine sediments had accumulated. In these zones, phosphorus is trapped in the bed sediments in calcium-bound phosphates due to precipitation processes. Copyright © 2005 John Wiley & Sons, Ltd.

[1]  Michael J. Wiley,et al.  Empirical relationships between land use/cover and stream water quality in an agricultural watershed , 1988 .

[2]  L. M. Svendsen,et al.  Retention of nitrogen and phosphorus in a Danish lowland river system: implications for the export from the watershed , 1993, Hydrobiologia.

[3]  J. Dorioz,et al.  Dynamique du phosphore dans les bassins versants: Importance des phenomenes de retention dans les sediments , 1989 .

[4]  H. Golterman.  Fractionation of sediment phosphate with chelating compounds: a simplification, and comparison with other methods , 1996, Hydrobiologia.

[5]  S. Jørgensen,et al.  Contribution of point sources and diffuse sources to nitrogen and phosphorus loads in lowland river tributaries , 2003 .

[6]  W. Saunders,et al.  OBSERVATIONS ON THE DETERMINATION OF TOTAL ORGANIC PHOSPHORUS IN SOILS , 1955 .

[7]  E. Loigu,et al.  Nutrient losses from agricultural areas in the Gulf of Riga drainage basin , 2000 .

[8]  Berit Arheimer,et al.  Nitrogen and phosphorus concentrations from agricultural catchments—influence of spatial and temporal variables , 2000 .

[9]  C. Soulsby,et al.  Hydrological controls on nutrient concentrations and fluxes in agricultural catchments. , 2002, The Science of the total environment.

[10]  Darren S. Baldwin,et al.  The effects of drying and re-flooding on the sediment and soil nutrient dynamics of lowland river-floodplain systems: A synthesis , 2000 .

[11]  William A. House,et al.  Geochemical cycling of phosphorus in rivers , 2003 .

[12]  W. House,et al.  Total phosphorus content of river sediments in relationship to calcium, iron and organic matter concentrations. , 2002, The Science of the total environment.

[13]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[14]  Michel Detay,et al.  River bank filtration: modelling of the changes in water chemistry with emphasis on nitrogen species , 1997 .

[15]  Donald E. Weller,et al.  Nutrient flux in a landscape: Effects of coastal land use and terrestrial community mosaic on nutrient transport to coastal waters , 1992 .

[16]  Andrew N. Sharpley,et al.  Identifying Sites Vulnerable to Phosphorus Loss in Agricultural Runoff , 1995 .

[17]  J. Dominik,et al.  Characterisation of bed sediments and suspension of the river Po (Italy) during normal and high flow conditions. , 2003, Water research.

[18]  Petri Ekholm,et al.  Relationship between catchment characteristics and nutrient concentrations in an agricultural river system , 2000 .

[19]  Daniel E. Storm,et al.  EFFECT OF A POINT SOURCE INPUT ON STREAM NUTRIENT RETENTION 1 , 2001 .

[20]  J. P. Riley,et al.  A modified single solution method for the determination of phosphate in natural waters , 1962 .

[21]  W. House,et al.  Precipitation of calcite in the presence of inorganic phosphate , 2002 .

[22]  W. House,et al.  Phosphorus and dissolved silicon dynamics in the River Swale catchment, UK: a mass‐balance approach , 2001 .

[23]  W. Edwards,et al.  Baseflow and Stormflow Transport of Nutrients from Mixed Agricultural Watersheds , 1991 .

[24]  E. Prepas,et al.  Nutrient dynamics in riverbeds: The impact of sewage effluent and aquatic macrophytes , 1994 .

[25]  O. Atteia,et al.  Particle size distributions in waters from a karstic aquifer: from particles to colloids , 1997 .

[26]  George C. Zalidis,et al.  Impacts of agricultural practices on soil and water quality in the Mediterranean region and proposed assessment methodology , 2002 .

[27]  D. Walling,et al.  Storage of sediment-associated nutrients and contaminants in river channel and floodplain systems , 2003 .

[28]  D. Keeney,et al.  Des Moines River Nitrate in Relation to Watershed Agricultural Practices: 1945 Versus 1980s , 1993 .

[29]  Patrick J. Mulholland,et al.  Regulation of nutrient concentrations in a temperate forest stream: Roles of upland, riparian, and instream processes , 1992 .

[30]  S. Payraudeau,et al.  Sediment and nutrient flood loads in three small Mediterranean catchments , 2003 .

[31]  D. Walling,et al.  The phosphorus content of fluvial sediment in rural and industrialized river basins. , 2002, Water research.

[32]  L. M. Svendsen,et al.  Dynamics of phosphorus compounds in a lowland river system: Importance of retention and non‐point sources , 1995 .

[33]  D. Walling,et al.  Downstream changes in the transport and storage of sediment-associated contaminants (P, Cr and PCBs) in agricultural and industrialized drainage basins. , 2001, The Science of the total environment.

[34]  E. Beauchamp,et al.  Leaching of Nitrogen and Phosphorus from the Biomass of Three Cover Crop Species , 1994 .

[35]  R. Perry,et al.  THE ADSORPTION AND RELEASE OF PHOSPHATE FROM SEDIMENTS OF A RIVER RECEIVING SEWAGE EFFLUENT , 1989 .

[36]  Darren S. Baldwin,et al.  The phosphorus composition of a diverse series of Australian sediments , 1996, Hydrobiologia.

[37]  Exchange of phosphorus across the sediment-water interface , 1988 .

[38]  B Picot,et al.  Phosphate adsorption and release from sediments of brackish lagoons: pH, O2 and loading influence , 1999 .

[39]  W. Raaphorst,et al.  Ammonium adsorption in superficial North Sea sediments , 1996 .

[40]  R. W. Skaggs,et al.  Hydrologic and water quality impacts of agricultural drainage , 1994 .

[41]  Richard J. Williams,et al.  Phosphorus-calcium carbonate saturation relationships in a lowland chalk river impacted by sewage inputs and phosphorus remediation: an assessment of phosphorus self-cleansing mechanisms in natural waters. , 2002, The Science of the total environment.

[42]  G. Millward,et al.  Kinetics of phosphate adsorption by iron oxyhydroxides in aqueous systems , 1984 .