EDAFOLOGÍA, Vol. 12 (1), pp. 53-64, 2005
EVALUACIÓN DE LA EROSIÓN Y CONTAMINACIÓN BAJO DIFERENTES INTENSIDADES DE RECOLECCIÓN CON CUBIERTAS DE ORÉGANO (Origanum Bastetanum L.) EN LANJARÓN (SE ESPAÑA)
C.R. RODRÍGUEZ PLEGUEZUELO*, V.H. DURÁN ZUAZO, J.R. FRANCIA MARTÍNEZ, A. MARTÍNEZ RAYA, B. CÁRCELES RODRÍGUEZ.
Centro de Investigación y Formación Agraria de Granada. IFAPA. Apdo. 2027. 18080, Granada, España. *[email protected]
Soil erosion, runoff (1997-2000), and nutrient losses were evaluated (NPK) (1998-2000) with Origanum bastetanum L. plant cover in Lanjarón (Granada, Spain), with four closed plots 96 m2 in area (4 x 24 m) at 20% of slope. Four harvest intensities were applied to the plant: no harvest (T-0), 25% (T-25), 50% (T-50), and 75% (T-75). The maximum rate of runoff was recorded in 1997 with T-75 (93,7 mm), and the minimum in 2000 with T-0 (3,9 mm). With regard to T-75, the runoff diminished 32, 30 and 19% for T-0, T-25 and T-50, respectively. The minimum rate of erosion was measured in 2000 with T-0 (0,2 Mg ha-1) and maximum in 1997 with T-50 (12,2 Mg ha-1), similar to T-75 (11,0 Mg ha-1). The mean soil erosion and runoff were increased following T-75>T-50>T-25>T-0. The NH4+ and H2PO4- in runoff rose the maximum concentrations recommended for drinkable water and for the eutrophication of superficial waters. The NO3- and K+were within the recommeded concentrations. The present study remarks the erosion and pollu- tion risk in mountainous land of semi-arid areas, highlighting the importance of the rational plant harvest in order to protect the soil.
Key words: erosion, harvest intensity, Origanum bastetanum L., runoff, semiarid areas