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Infiltration and percolation rates are influenced by soil water content, but the effects of soil water on these two parameters have not been separated. Our objective was to clarify some of the effects of initial soil water content, time, and an interruption of soil water flow on infiltration and percolation. Infiltration and percolation measurements were made by ponding soil cores and by using a double ring infiltrometer and a sprinkling infiltrometer in the field. Aggregate stability measurements were made on field-collected surface soil. The infiltration rate after one hour of water application on soils above 15% antecedent soil water content was greater than on the same soil at less than 5% antecedent soil water content. Wet aggregate stability measurements followed the same trend. It is suggested that the slow breakdown of aggregate bonds under wet conditions causes this phenomenon. In contrast, percolation rates were higher with higher soil water contents. An interruption in water application for percolation measurements reduced the wet rates more than the initially dry rates. It is suggested that air bubble entrapment is the main retardant to percolation for both the initially dry situations and for interrupted flow.

Phytoremediation offers the benefits of being in situ, low cost and environmentally sustainable. Lupinus species is starting to generate interest for phytoremediation of soils showing intermediate metal pollution. The aim of this study was to explore the accumulating behavior and tolerance of Lupinus uncinatus Schldl. towards increasing Cd concentrations in soil. For this purpose the effects of different Cd treatments on plant growth, survival, metal tolerance, Cd accumulation and distribution in various plant organs were investigated. An 18 week pot trial was performed under greenhouse conditions. Cd was added as CdCl2.2.1/2H2O at the rate of 0, 3, 6 and 9 mg Cd/kg soil at three different occasions (after 4th, 12th and 15th week of plant growth) with four replicates. The Cd treatments applied, thus, were 9, 18 and 27 mg/kg. Cd inhibited plant height and number of leaves and induced a significant change in dry matter yield of roots, stems and leaves. Metal tolerance indices of 88, 82 and 49% were obtained for 9, 18 and 27 mg Cd/kg treatments. The maximal shoot Cd concentration (stem+leaves) of 540 mg Cd/kg dry matter was found at 27 mg Cd/kg treatment. The poor translocation of Cd from roots to shoot was evident from shoot:root ratios La fitorremediación tiene las ventajas de ser in situ, de bajo costo y sustentable para el ambiente. El objetivo del presente trabajo fue explorar la acumulación y tolerancia de Cd por Lupinus uncinatus en suelos contaminados con Cd. Se investigó el efecto de diferentes tratamientos de Cd sobre el crecimiento y supervivencia de la planta, tolerancia al metal, así como acumulación y distribución del Cd en diferentes órganos de la planta. El experimento se llevó a cabo en macetas bajo condiciones de invernadero durante 18 semanas. Se agregó CdCl2.2.1/2H2O después de 4, 12, y 15 semanas del crecimiento en las siguientes concentraciones (0, 3, 6, 9 mg Cd/kg suelo) con cuatro repeticiones. El Cd inhibió altura de la planta y número de hojas e indujo un cambio significativo en el rendimiento de la materia seca de las raíces, hojas y tallos. El índice de tolerancia al metal fue 88, 82 y 49% para los tratamientos 9, 18 y 27 mg Cd/kg respectivamente. Se detectó una concentración máxima en parte aérea (540 mg Cd/kg materia seca) en el tratamiento 27 mg Cd/kg. La translocación desde la raíz hacia el tallo fue pobre y la proporción del Cd en raíz:tallo fue