Publications by authors named "Cledimar Rogerio Lourenzi"

Viticulture allows the preservation of native species inside vineyards in the Pampa biome. However, phytosanitary treatments in these areas can increase the levels of Cu, Zn and Mn. The study aimed to (i) verify the influence of Cu, Zn and Mn contents in Pampa biome soils; (ii) identify variables related to Cu, Zn and Mn that most contribute to the variation in richness, diversity, and dry matter production of native vegetation, (iii) investigate the phytoremediation potential of species present in vineyards.

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Background: Soil quality (SQ) assessment is affected by methods that convert data sets into indices, and such analyses are expensive and time-consuming. Qualitative SQ assessments are faster and cheaper than quantitative methods and they can be repeated to monitor SQ in crop and pasture systems. We evaluated SQ using qualitative and quantitative SQ indicators of two grazing systems under Voisin rational grazing (VRG) with trees (WT) or without trees (NT).

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Several studies have reported increased copper (Cu) and zinc (Zn) levels in agricultural soils worldwide, mainly due to organic waste and successive leaf fungicide applications in crops. However, the critical transfer thresholds in soils, which can indicate the real risk of environmental contamination and toxicity to plants, remain poorly understood. This study aimed to define the maximum Cu and Zn adsorption capacity (MAC) and threshold (T-Cu and T-Zn) in different soils in Southern Brazil, which present different clay and organic matter (OM) levels.

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Copper (Cu) can be toxic to vegetables when it is absorbed and accumulated at large concentrations, a fact that increases the risk of excessive addition of this metal to the human food chain. The aims of the current study are (1) to determine the Cu concentrations that have critical toxic effects on beet and cabbage plants, and the potential of these plants to enter the human food chain, as well as (2) to assess the physiological and biochemical responses of representatives of these vegetables grown in nutrient solution presenting increasing Cu concentrations. Beet and cabbage plants were grown for 75 days in pots filled with sand added with nutrient solution presenting six Cu concentrations: 0.

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Background: The natural abundance of stable isotope N (δ N) in production systems has emerged as an alternative to distinguish organic products from conventional ones. This study evaluated the use of δ N values recorded for nitrogen fertilizers, soil and plant tissue in order to set the differences between organic and conventional agricultural production systems applied to rice, potatoes, apple and banana crops.

Results: Values of δ N recorded for N sources ranged from +5.

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Some species of cover crops produce phenolic compounds with allelopathic potential. The use of math, statistical and computational tools to analyze data obtained with spectrophotometry can assist in the chemical profile discrimination to choose which species and cultivation are the best for weed management purposes. The aim of this study was to perform exploratory and discriminant analysis using R package specmine on the phenolic profile of L.

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Association of rhizobia with other plant growth-promoting bacteria (PGPB), such as Azospirillum, have the potential to increase crop yields. This work aimed to assess how Rhizobium tropici and Azospirillum brasilense alone or in combination, affect the growth and yields of common bean grains (Phaseolus vulgaris L.).

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This study aims to evaluate available Cu and Zn levels in soil and related in soil organic matter (SOM) fractions (fulvic acids-FA, humic acids-HA, and humins-HU) after 10 years of application of pig slurry (PS) and pig deep litter (PL). Soil samples were collected from an experiment with black oat/corn succession under no-tillage in southern Brazil. The treatments consisted of fertilization of 90 and 180 kg N ha applied as PS and PL from 2002 to 2012 and a control treatment without any fertilization.

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Successive swine effluent applications can substantially increase the transfer of phosphorus (P) forms in runoff. The aim of this study was to evaluate P accumulation in the soil and transfer of P forms in surface runoff from a Hapludalf soil under no-tillage subjected to successive swine effluent applications. This research was carried out in the Agricultural Engineering Department of the Federal University of Santa Maria, Brazil, from 2004 to 2007, on a Typic Hapludalf soil.

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