Nutrient losses from a vineyard soil in Northeastern Spain caused by an extraordinary rainfall event

Vineyards are one of the lands that incur the highest soil losses in Mediterranean environments. Most of the studies that report about this problem only focus on soil losses and few investigations have addressed the nutrient losses associated with erosion processes during the storms. The present research evaluates the loss of nitrogen, phosphorus and potassium in vineyard soils located in a Mediterranean area (NE Spain), after an extreme rainfall event recorded on 10 June 2000. The total rainfall of this event was 215 mm, 205 mm of which fell in 2 h 15 min. The maximum intensity in 30-min periods reached 170 mm h(-1). This rainfall produced a large amount of sediments both inside and outside the plots, with the consequent soil mobilisation and loss of nutrients. The estimate of soil loss was based on the subtraction of two very accurate digital elevation models (DEMs) of different dates in GIS, and measures of the nutrient content of sediment collected in the plot. Soil loss in the study plot reached 207 mg ha(-1). Most sediment was produced by concentrated surface runoff. Nutrient losses, amounted as 108.5 kg ha(-1) of N, 108.6 kg ha(-1) of P and 35.6 kg ha(-1) of K. The proposed method allowed mapping the sediment contribution and deposition areas and the distribution of the nutrient load and losses within the plot. (C) 2003 Elsevier Science B.V. All rights reserved.