Soil degradation in central Spain due to sheet water erosion by low-intensity rainfall events
Version of Record online: 18 JUL 2007
Copyright © 2007 John Wiley & Sons, Ltd.
Earth Surface Processes and Landforms
Volume 33, Issue 3, pages 414–423, March 2008
How to Cite
Marques, M. J., Bienes, R., Pérez-Rodríguez, R. and Jiménez, L. (2008), Soil degradation in central Spain due to sheet water erosion by low-intensity rainfall events. Earth Surf. Process. Landforms, 33: 414–423. doi: 10.1002/esp.1564
- Issue online: 28 FEB 2008
- Version of Record online: 18 JUL 2007
- Manuscript Accepted: 30 MAY 2007
- Manuscript Revised: 16 MAY 2007
- Manuscript Received: 1 MAR 2007
- Consejería de Educación de la Comunidad de Madrid. Grant Numbers: SC98-031-C3, 07M/0009/2001, FP02-DR1
- gypsiferous soil;
- organic matter;
- rainfall intensity;
- soil degradation
Runoff and sediment lost due to water erosion were recorded for 36 (1 m2) plots with varying types of vegetative cover located on sloping gypsiferous fields in the South of Madrid. 75% of the events had maximum 30-minute intensity (I30) less than 10 mm h−1 in the period studied (1994–2005).
As for the vegetative cover, maximum correlation between runoff and soil loss was found in the least protected plots (0–40% cover) during the most intense rainfall events; however, a significant positive correlation was also observed in plots with greater coverage (40–60%). If coverage exceeded 60%, rainfall erosivity declined.
The average amount of sediment produced in high-intensity events was significantly greater (approximately 7 g m−2 per I30 event >10 mm h−1) than that produced in the rest of the moderate-intensity events (approximately 3 g m−2 per I30 event <10 mm h−1), but due to the high rate of occurrence of the latter throughout the year sediment loss during the period studied totaled 128 g m−2. By comparison, only 40 g m−2 was produced by the I30 events greater than 10 mm h−1.
Even though the amount of soil lost is relatively insignificant from a quantitative standpoint, the organic matter content lost in the sediment (six times more than in the soil) is a permanent loss that threatens the development of the surface of the soil in this area when the vegetative cover is less than 40%. The soil here experiences a chronic loss of 0·02 mm annually as a consequence of frequent, moderate events, in addition to any loss produced by extraordinary events, which, though less frequent, are much more erosive. If moderate events are ignored, an important part of soil loss will be lost in the long run. Copyright © 2007 John Wiley & Sons, Ltd.