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All publications of “Leonardus Vergütz”

6 results

Functionalized Charcoal as a Buffering Matrix of Copper and Zinc Availability

Gelton Geraldo Fernandes Guimarães, Amanda Soares Giroto, Breno Cardoso Teixeira, Leonardus Vergütz, Reinaldo Bertola Cantarutti

02/Nov/2018

ABSTRACT: High copper (Cu) and zinc (Zn) contents in soil can cause phytotoxicity to plants and contaminate surface and groundwater, with negative effects on agriculture and the environment. Functionalized charcoal (OCh) has high cation exchange capacity (CEC) and the ability to adsorb Cu and Zn and control their availability in the soil and water. An adsorption study at two pH levels was carried out to evaluate increasing Cu and Zn sorption capacity provided by the functionalization process of a charcoal. […]

Physiological Responses to Hypoxia and Manganese in Eucalyptus Clones with Differential Tolerance to Vale do Rio Doce Shoot Dieback

Ignácio Harguindeguy, Gustavo Franco de Castro, Sarah Vieira Novais, Leonardus Vergutz, Wagner Luiz Araujo, Roberto Ferreira Novais

19/Jan/2018

ABSTRACT: Vale do Rio Doce shoot dieback (VRDSD) is an anomaly whose cause seems to be associated with hypoxic conditions and their consequences (excess Mn and Fe) triggered by elevation of the water table in areas with poor drainage. Different plants have distinct survival strategies under this form of stress. The objective of this study was to understand the physiological responses involved in the differential tolerance of eucalyptus clones to VRDSD and their relationship to hypoxia and excess Mn. A […]

Iron Availability in Tropical Soils and Iron Uptake by Plants

Guilherme Furlan Mielki, Roberto Ferreira Novais, João Carlos Ker, Leonardus Vergütz, Gustavo Franco de Castro

05/Oct/2016

ABSTRACT Given the increase in crop yields and the expansion of agriculture in low fertility soils, deficiency of micronutrients, such as iron, in plants grown in tropical soils has been observed. The aim of this study was to evaluate Fe availability and Fe uptake by corn (Zea mays L.) plants in 13 different soils, at two depths. Iron was extracted by Mehlich-1, Mehlich-3, and CaCl2 (Fe-CC) and was fractionated in forms related to low (Feo) and high (Fed) crystallinity pedogenic […]

Thermodynamic Characterization of Humic Acid-surfactant Interaction: New Insights into the Characteristics and Structure of Humic Acids

Leonardus Vergütz, Luis Henrique Mendes da Silva, Roberto Ferreira Novais, Maria do Carmo Hespanhol da Silva, Aparecida Barbosa Mageste, Ivo Ribeiro Silva

01/Dec/2015

ABSTRACT Humic acids (HA) are a component of humic substances (HS), which are found in nearly all soils, sediments, and waters. They play a key role in many, if not most, chemical and physical properties in their environment. Despite the importance of HA, their high complexity makes them a poorly understood system. Therefore, understanding the physicochemical properties and interactions of HA is crucial for determining their fundamental role and obtaining structural details. Cationic surfactants are known to interact electrostatically and […]

LOSS OF EXTRACTION CAPACITY OF MEHLICH-1 AND MONOCALCIUM PHOSPHATE AS A VARIABLE OF REMAINING P AND ITS RELATIONSHIP TO CRITICAL LEVELS OF SOIL PHOSPHORUS AND SULFUR

Sarah Vieira Novais, Edson Marcio Mattiello, Leonardus Vergutz, Leônidas Carrijo Azevedo Melo, Írio Fernando de Freitas, Roberto Ferreira Novais

01/Jul/2015

The Mehlich-1 (M-1) extractant and Monocalcium Phosphate in acetic acid (MCPa) have mechanisms for extraction of available P and S in acidity and in ligand exchange, whether of the sulfate of the extractant by the phosphate of the soil, or of the phosphate of the extractant by the sulfate of the soil. In clayey soils, with greater P adsorption capacity, or lower remaining P (Rem-P) value, which corresponds to soils with greater Phosphate Buffer Capacity (PBC), more buffered for acidity, […]

LAYERED DOUBLE HYDROXIDES: NANOMATERIALS FOR APPLICATIONS IN AGRICULTURE

Luíz Paulo Figueredo Benício, Rejane Alvarenga Silva, Júnia Aparecida Lopes, Denise Eulálio, Rodrigo Morais Menezes dos Santos, Leonardo Angelo de Aquino, [...]

01/Jan/2015

The current research aims to introduce Layered Double Hydroxides (LDH) as nanomaterials to be used in agriculture, with particular reference to its use as storage and slow release matrix of nutrients and agrochemicals for plant growing. Structural characteristics, main properties, synthesis methods and characterization of LDH were covered in this study. Moreover, some literature data have been reported to demonstrate their potential for storage and slow release of nitrate, phosphate, agrochemicals, besides as being used as adsorbent for the wastewater […]