Heterogeneidad espaciotemporal del sedimento de los arrozales del delta del Ebro (NE de España) Time-space heterogeneity in the sediments of the ricefields from the Ebro delta (NE Spain)

Time-space heterogeneity in the sediments of the ricefields from the Ebro delta (NE Spain). Nutrients and other physical and chemical parameters were studied in ricefield sediments of the Ebro Delta in order to describe their changes during the growing period. C, N, P, Ca, Al, Mg, organic matter and water content were analyzed. Also granulometric analysis were performed. A comparison of sediment nutrient contents and particle size in four ricefilds was made in order to know which are the differences between ricepaths in the Ebro Delta. The results show that rice growth and denitrification seem to play an important role in the variation of nitrogen concentration with time. In the other hand changes in the physical and chemical characteristics of the inundation water during growing period explained the variation of phosphorus concentration in the last phases of the cultivation period. From the studied parameters, organic matter contents and texture of sediments were the best parameter to explain the differences between ricefields in the Ebro Delta.