Nutrient Availability and Changes on Chemical Attributes of a Paleudult Soil Amended with Liquid Sewage Sludge and Cropped with Surinam Grass

Figure 1

Changes in annual values of pH, soil organic matter (OM), and phosphorus and potassium concentrations, at two soil depth layers (0–20 and 20–40 cm), in experimental plots treated with and without sewage sludge (SS) during four years (2003 to 2006) and cultivated with grass (Brachiaria decubens).

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