Nutrient losses by runoff in vineyards of the Mediterranean Alt Penedès region (NE Spain)

摘要: Abstract This paper deals with nutrient (N and P) losses by runoff in vineyards of the Penedes area (north-eastern Spain), their relationship rainfall erosivity. The study was carried out a commercial vineyard, which levelled previous to vineyard establishment order adapt fields mechanised labours, leaving on top surface soils very low organic matter content susceptible erosion. After levelling, large inputs wastes before and/or after planting were incorporated improve soil properties. analysis done under natural during period 2000–2001, 17 events recorded. Runoff ratios varied from 2.9 28.6%, except for two extreme up 55.8 80% ran off, respectively. Sediment concentration variable ranging between 25.3 g L −1 depending erosivity, also affected losses. Erosion processes exported significant amounts nutrients, represent about 8 kg ha  year N 6.5 kg ha P, without taking into account events. results point that most are due small number recorded every year, can contribute more than 60% annual