Uma leitura geográfica da educação no campo: o caso da Escola Municipal Agrícola de Rio Claro - SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A constituição do círculo de cooperação de pesquisa agrícola no Brasil: nova face do uso corporativo do território brasileiro no período técnico-científico-informacional

Pós-graduação em Geografia - IGCE

Serie lecturas sobre desarrollo agrícola

V. 1: Teorías económicas y análsis histórico del desarrollo agrícola; v. 2: Agricultura comparada; v 3: Recursos naturales en el desarrollo agropecuario; v. 4: Desarrollo rural integrado (DRI)

Industria de maquinaria agrícola: lineamientos generales para una política sectorial

Incluye Bibliografía

Sector agrícola en los esquemas de integración económica de América Latina = Agricultural sector in the economic integration systems of Latin America

Incluye Bibliografía

Infraestructura, transporte y desarrollo productivo de una región agrícola: un caso de Argentina

En un estudio reciente realizado por la CEPAL se analiza el desarrollo de la zona agrícola situada en el centro y norte de Argentina, por cuyos puertos sale más del 80% de las exportaciones agrícolas del país, en volumen. Las exportaciones del complejo agroindustrial equivalen al 58% del valor total de las ventas argentinas.Es sabido que, en general, las inversiones en infraestructura contribuyen a la reducción de los costos de las empresas y al aumento de la productividad. La hipótesis central del estudio es que las inversiones en infraestructura de transporte constituyen una condición necesaria para el desarrollo productivo de una región, en particular aquella ligada al comercio exterior, como los puertos y las vías navegables.En el caso de Argentina, se ha constatado una relación positiva entre la evolución de las prestaciones de servicios portuarios e hidroviarios (con menores costos y tiempos operativos, mayor confiabilidad y nuevos servicios), y la expansión de la frontera agrícola, el crecimiento de la productividad y la producción agrícola, y su industrialización.

Políticas públicas no Município de Junqueirópolis (SP): o PRONAF e o PAA

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluación de impactos del cambio climático sobre la producción agrícola en la Argentina

Incluye biblografía.

Avaliação do potencial de uso agrícola da fluorita com óxido silício (AgroSiCa), derivado da fabricação de fertilizantes fosfatados

Phosphate fertilizers are critical for crop production in tropical soils, which are known for having high phosphate-fixing capacity and aluminium saturation, as well as low pH and calcium contents. Fluorine is a component of many phosphate rocks used to make phosphate fertilizers, via a process that generates hexafluorosilicic acid (H2SiF6). While many treatment technologies have been proposed for removal of fluorine in industrial facilities, little attention has been given to a process of neutralizing H2SiF6 with calcium oxide aiming to find out an alternative and sustainable use of a by-product with a great potential for beneficial use in tropical agriculture. This study evaluated the effect of a by-product of phosphoric acid production (fluorite with silicon oxide, hereafter called AgroSiCa) in levels of phosphorus (P), calcium (Ca), silicon (Si), aluminum (Al) and fluorine (F) and some others parameters in soils as on growth of soybean and corn. Experiments were conducted in a greenhouse condition at the Federal University of Lavras (UFLA), Lavras, Minas Gerais, using different types of soils in tropical regions and different doses of AgroSiCa. The application of AgroSiCa resulted in a slight increase in soil pH and significant increases in calcium, phosphorus and silicon in the soil solution and the shoots of corn and soybeans. We also found very low levels of fluoride in all soil leachates. A significant reduction of labile aluminum levels found in all soils after the cultivation of corn and soybeans. In sum, AgroSiCa improved soil properties and contributed to better growth of both cultures. In sum, AgroSiCa improved soil properties and contributed to a better growth of both crops. Our results show that reacting H2SiF6 derived from the wet-process phosphoric acid production with calcium oxide leads to a by-product with potential for agricultural use, especially when applied in highly-weathered soils. Besides providing calcium and silicon to plants, the use of such by-product in soils with high phosphate-fixing capacity and high aluminium saturation delivers additional benefits, since fluoride and silicon can play an important role in improving soil conditions due to the formation of less plant-toxic forms of aluminium, as well as upon decreasing phosphate fixation, thus improving root development and making fertilizer-derived phosphate more available for plant growth.

Caracterização de lodo gerado em estações de tratamento de água: perspectivas de aplicação agrícola

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Propriedades físico-químicas e produção da Brachiaria brizantha em um latossolo vermelho fertilizado com Ajifer L-14

Pós-graduação em Agronomia - FEIS