In order to assess the changes in some chemical properties of soil under the successive addition of urban waste compost, it was conducted a field experiment in an Ultisol soil at Agronomic Experimental Station of UFRGS. The treatments consisted of five successive applications of different doses of municipal solid waste compost (0, 20, 40, 80 and 160t ha-1) for a period of four years and a comparative treatment with mineral fertilizer and a control (without compost and fertilization). The addition of the compost increased soil pH, CEC, organic C, total N, extractable P and Na and the sodium adsorption ratio (SAR), calcium, and magnesium and extractable K after the third application. The exchangeable Al had their levels reduced by successive applications of compost. The results showed that application of up to 80t ha-1 yr-1 of urban waste compost can be the dose recommended to improve and maintain the chemical properties of soil.
pH; CEC; organic C; total N; nutrient availability
