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++ 4 tab. 16 ref. Sum. (En, Pt)

Some physico-hydric and chemical characteristics of Vertisols (Chromuderts) at levels to 135 cm deep were evaluated namely: saturated hydraulic conductivity (cm.day exponent -1); bulk density and particle density (g.cm exponent -3) soil water availability (percent), available phosphorus (ppm), exchangeable calcium, magnesium, potassium and sodium (meq.100 g exponent -1) and pH. The average saturated hydric conductivity was very slow (4.7 cm.day exponent -1). In the soils saturated (0.58 cm.cm exponent -3) the values of bulk density were 1.07 to 1.11 g.cm exponent -3 to 60 cm of depth and 1.26 g.cm exponent -3 till 135 cm; the values were high with less humidity in the soil, due to the type of clay. The particle density till 75 cm was 2.47 g.cm exponent -3, average value for mineral soils; at the 90-105 and 120-135 cm depths the values were 2.70 and 2.77 g.cm exponent -3, respectively. The available water in the soil varied from 4.4 to 7 percent to 90 cm of depth, and 11 percent at 105-120 cm. The exchangeable calcium and magnesium were very high, respectively 39.6 and 16.6 meq.100 g exponent -1 in the top layer and high in the other layers. The potassium content was high, 0.30 meq.100 g exponent -1 for 0-15 cm and 0.18 meq.100 g exponent -1 for 120-135 cm depth. The available phosphorus was very low (2 ppm) and low (7 ppm) in the 120-135 cm layer. The exchangeable sodium was 0.46 meq.100 g exponent -1 in the 0.15 cm layer and 3.87 meq.100 g exponent -1 for the 105-120 cm. The pH was 6.7 at 0-15 cm, increasing to 8.1 at 120 to 135 cm. The hydric deficit in certain years sharply limits cacao production. But till, this crop is a promising alternative for use as the litter cover improves the physical and chemical properties of the soil.

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