Resumen

FERNANDEZ, Juan Alfredo, SCHROEDER, María Andrea, GOLDFARB, María Cristina et al. Efecto de la frecuencia de quema prescripta sobre la composición mineral de los pastizales en el nordeste argentino. Ecol. apl., ene./agos. 2011, vol.10, no.1, p.23-29. ISSN 1726-2216.

In order to evaluate the concentration of mineral components of the grasslands under different management systems of prescribed burning, we designed a trial in the EEA INTA Corrientes, Argentine. The study area was not burned for a period of 20 years. The design used corresponded to a split plot arrange and RCB design, with four replications. The treatments were: T0=without burning, T1=annual burning and T2=biennial burning. The burning was carried out in late winter. Sampling was conducted every four seasons. The determination of Na, K, Ca and microelements (Fe, Cu, Mn and Zn) was performed with atomic absorption spectrophotometry and P by UV-visible spectrophotometry. The results were analyzed by ANOVA and Duncan test. In none of the elements considered there were interactions between seasons and burning treatments. The P, Ca and Na in the biennial burning treatment were significantly higher than the annual burning. The K content was unaffected by the treatments applied. There were no differences between treatments for micronutrients, but there were differences between different seasons. The highest concentrations were recorded in summer and autumn for Mn and Fe, and in autumn-winter for Zn and Cu. The biannual burns treatment had significantly increased concentrations of P, Ca and Na of the grassland.

Palabras llave: naturals grassland; prescribed burning; mineral nutrients.