Anais do XXXV Congresso Brasileiro de Ciência do Solo
CHARACTERISTICS, DISTRIBUTION AND PHOSPHORUS RELEASE FROM FLUVIAL SEDIMENTS IN A MIXED LAND USE CATCHMENT, SOUTHERN BRAZIL
MOHSIN ZAFAR(1); DANILO RHEINHEIMER DOS SANTOS(1); VIVIANE CAPOANE(1); JOSE AUGUSTO CASTRO DE LIMA(1); ALEXANDRE TORIAN(1); 1 - UNIVERSIDADE FEDERAL DE SANTA MARIA;
During past two decades, the increase in animal production in South America has ranked second globally and as result phosphorus (P) export from soil surface along with sediments has increased. The study area Guapore catchment is located between latitudes 29.2 S and 28.2 S and longitude 52.4 W and 51.8 W in Southern Brazil with basin area of 2500 km2. A total of 11 points under different anthropic disturbances including conventional tillage (CT) and no-tillage (NT) systems were selected. At each monitoring point the SS were collected in November, 2013. The Hedley P fractionation scheme was followed to separate different P fractions.The phosphorus fractionation results showed an overall trend of the P forms was NaOH-P (Fe and Al bound P) >> Residual-P > HCl-P (Ca bound P) > NaHCO3-P (labile P) > Resin-P (bioavailable P). Across different land-use systems, CT showed greater retention of the P as well as desorbed more bioavailable P during ecologically sensitive periods. The results demonstarte hat the soil application of manure must be based on P availability and not on total P basis to minimize hazardous environmental impacts.
Certificados
Início
