4 results

Characterization of erosive rainfall in Urussanga, SC, Brazil in regard to the temporal distribution pattern

Morgana Levati Valvassori, Álvaro José Back

01/Jun/2014

The study of temporal distribution of rainfall is carried out to characterize the most frequent rainfall patterns. Knowledge of the physical characteristics of rainfall in relation to rainfall patterns allows mathematical modeling to be performed in regard to hydrologic events more nearly approaching real conditions. The objective of this study was to characterize the erosive rains from the municipality of Urussanga, SC, Brazil in regard to hydrological patterns of temporal distribution. Rainfall records from the meteorological station of Urussanga (28.31° […]

Ammonium and nitrate seasonal and daily fluctuation in a Typical Red Dysthropic Argisol

Naracelis Poletto, Daniel Santos Grohs, Claudio Mario Mundstock

01/Aug/2008

Ammonium and nitrate ions from soil organic N mineralization are the predominant N mineral forms available to plants. The ion ratio and distribution along the soil profile show daily fluctuations and oscillate seasonally. NH4+ and NO3– soil content were evaluated in two adjacent plots, one of them farmed continuously with barley, soybean and barley in a no-tillage system for more than 10 years, with pH 6.0 and fertilized with P and K. A second plot was maintained undisturbed, with native […]

Rainfall erosivity in Uruguaiana, Rio Grande do Sul, Brazil from 1963 to 1991 determined by the EI30 index

Clério Hickmann, Flávio Luiz Foletto Eltz, Elemar Antonino Cassol, Clarissa Melo Cogo

01/Apr/2008

Rainfall erosivity represents the potential of rainfall causing soil erosion. The EI30 index is a method to determine rainfall erosivity and is calculated by the product of the total kinetic energy of rainfall and the maximum intensity in 30 min. The objective of this study was to calculate rainfall erosivity in Uruguaiana, RS, Brazil, for practical applications in soil conservation, based on daily rainfall charts. For each rainfall chart, segments with the same intensity were separated, registered in worksheets, digitalized and […]

Analysis of mathematical models applied to the study of intense rainfall

C. R. Mello, D. F. Ferreira, A. M. Silva, J. M. Lima

01/Sep/2001

The estimate of maximum rainfall intensity is of great concern in agricultural projects such as the use of terraces for erosion control, dams, and soil water drainage. Rainfalls can be characterized by their intensity (mm h-1), duration time (min), and return period (years). One of the analyzed models has been used for estimating the maximum rainfall intensity to be applied in dimensioning such agricultural structures, for a given return period and storm duration. The time of concentration in small watersheds, […]