Water erosion in soils under eucalyptus forest as affected by development stages and management systems Eros o hídrica em solos sob floresta de eucalipto em diferentes estádios de desenvolvimento e sistemas de manejo

The constant increasing of eucalyptus forest areas in Brazil requires an accurate monitoring of water erosion. The present study aimed to evaluate soil, nutrients and organic carbon losses occasioned by water erosion in eucalyptus planted forests (EPF) at different development stages (2, 3 and 7 years old). Soil erosion sediments were measured and sampled from standard erosion plots installed on Red Argisol-RA (Ultisol) and Haplic Cambisol-HC (Inceptisol). Soil loss decreased as the age of plants increased; at the beginning of plant development, the canopy barely covered the soil surface, exposing the soil to higher erosion at young EPF plantations. Furrow planting system was used in the Red Argisol area and caused higher soil losses (1.1 to 6.2 Mg ha-1 year-1) as compared to pit planting system that was used in the Cambisol area (1.1 Mg ha-1 year-1). It is known that Cambisol is less resistant to erosion than Argisol. However, using pit system in this EPF, resulted in lower erosion and, therefore, nutrients and carbon losses than the traditional furrow system used in Argisol. Concerning the soil loss, this work points to the need of improving soil conservation practices to prevent soil erosion at the earlier stages of eucalyptus plantation. The amount of calcium and potassium were higher than magnesium in the soil sediment.The relatively high amount of carbon found in the erosion sediments raises additional concerns about the environmental sustainability and deserves future research. O aumento constante das áreas de florestas de eucalipto no Brasil imp e um monitoramento acurado da eros o hídrica. No presente estudo, objetivou-se avaliar as perdas de solo, nutrientes e carbono organico ocasionadas pela eros o hídrica em florestas plantadas de eucalipto em diferentes estádios de desenvolvimento (2, 3 e 7 anos). Os sedimentos de eros o foram medidos e amostrados por parcelas-padr o instaladas em Argissolo Vermelho (Ultisol) e Cambissolo Háplico (Inceptisol). As perdas de solo diminuíram com o aumento da idade das plantas; no início do desenvolvimento delas, o dossel apresentava pequena cobertura da superfície, expondo o solo das planta es jovens a maiores taxas de eros o. O sistema de plantio em sulcos utilizado no Argissolo Vermelho ocasionou maiores perdas de solo (1,1 a 6,2 Mg ha-1ano-1) quando comparado ao sistema de covas usado no Cambissolo Háplico (1,1 Mg ha-1ano-1). é conhecido que os Cambissolos (Inceptisol) é menos resistente à eros o do que os Argissolos (Ultisol). Contudo, a utiliza o do sistema de covas resultou em menor eros o e, conseque