Volume 37, Number 2, 2013

Pastures are the fodder supply of Brazilian livestock, and are exhaustively degraded by nitrogen (N) deficiency. Intercropping with legumes, aside from nitrogen fixation, may have secondary effects on soil fertility, such as acidification or nutrient movement from deeper to the surface soil layers. This study evaluated the soil litter stock and fertility of degraded Brachiaria decumbens pastures after planting leguminous shrubs and forage trees. For this purpose, we sampled (March 2010) degraded Brachiaria decumbens pasture planted in July 2008 in […]

The adoption of crop rotation and crop sequence systems is one of the fundamental prerequisites for the sustainability of agricultural production. Therefore, the objective of this study was to evaluate the effects of ryegrass desiccation time and nitrogen fertilizer applied at sowing of irrigated rice, in succession, as a management strategy in irrigated rice cultivation. The field experiment was carried out in two growing seasons (2008/09 and 2009/10), in Cachoeirinha, State of Rio Grande do Sul, Brazil, on a typical […]

Water erosion is the major cause of soil and water losses and the main factor of degradation of agricultural areas. The objective of this work was to quantify pluvial water erosion from an untilled soil with crop rows along the contour, in 2009 and 2010, on a Humic Dystrupept, with the following treatments: a) maize monoculture; b) soybean monoculture; c) common bean monoculture; d) intercropped maize and bean, exposed to four simulated rainfall tests of on hour at controlled intensity […]

Knowledge on rainfall erosivity associated to occurrence probability and return periods can contribute to conservation planning in the medium and long term. With the objective of generating information for a better use of medium and long-term erosion models and erosion control, rainfall data of 30 pluviometric and pluviographic data sets from 25 cities ranging from 1933 to 2006 were studied in terms of adjustment of data sets, calculation of the probability of theoretical occurrence (P) and return period (T) of […]

The use of audiovisual resources in soil teaching, as a stimulus for students, can be useful to develop students’ critical and reflexive knowledge. This study aimed to analyze the contribution of the video “Conhecendo o Solo” (“Knowing the Soil”) in teaching and learning about this subject in elementary school. In order to stimulate students to realize the importance of soils in the environment, the video was used as teaching content. Then, some questions were applied in which the students described […]