Volume 32, Number n.spe, 2008

In regions of temperate and subtropical humid climate in Brazil, below the parallel of 24° latitude South, the rainfall characteristics potentially exceed the soil water infiltration rate and produce runoff, at any time of the year, independent of soil use and management system. The additional conservational practices have not been fully adopted in the no-tillage system as it would be required to control the erosion potential due to the soil conditions of these regions. Runoff results in chemically enriched sediments, […]

The quality of commercial crop residues and green manure influences the N mineralization-immobilization rate and the respective use by subsequent crops. With the objective of evaluating N utilization by corn of N from the shoot and root system of sunnhemp (Crotolaria juncea) and millet (Pennicetum americanum) and corn straw, labeled with 15N, a green house experiment was carried out at the Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, S. Paulo, Brazil, in 5 kg pots with dystroferric Red Latosol […]

Tannery residues are potential pollution sources in several regions of Brazil, mainly in the State of Rio Grande do Sul. One of the alternatives for the final destination of the sludge resulting from the waste water treatment of tanning industries is the disposal and recycling in the soil. To evaluate the effects of two waste types originated from primary treatment of tannery residual water on soil microbial populations, an open air pot experiment was carried out in a Paleudult soil […]

Phosphate fertilizers contain heavy metals, including Cd, which is potentially toxic to humans, animals and plants. The objective of this study was to assess the bioavailability of Cd contained in phosphate fertilizers. Six phosphate fertilizers (two natural phosphates, two simple superphosphate, a triple superphosphate and a monoammonia phosphate) were selected for the study of bioavailability in a greenhouse experiment, using Avena strigosa as an indicator of the bioavailability of Cd. The Cd was bioavailable in phosphate fertilizers, since it was […]

Tannery residues and coal mine waste are heavily polluting sources in Brazil, mainly in the Southern States of Rio Grande do Sul and Santa Catarina. In order to study the effects of residues of chrome leather tanning (sludge and leather shavings) and coal waste on soybean and maize crops, a field experiment is in progress since 1996, at the Federal University of Rio Grande do Sul Experimental Station, county of Eldorado do Sul, Brazil. The residues were applied twice (growing […]

Soil contamination by heavy metals is a current concern that requires a suitable approach, taking the needs of modern societies into account. In mined areas the evaluation of soil contamination is an important tool for the management of degraded areas. This study was carried out in order to establish local reference values (LRV) for Zn in soils surrounding mining areas in the county of Vazante-MG (Brazil), with a view to evaluate the environmental contamination. Soil profiles were collected in the […]