Eduardo Arellano

Fertilizantes de entrega controlada: potencial para mejorar la productividad de la reforestación

Los fertilizantes de entrega controlada (FEC) presentan un gran potencial para aumentar la competitividad de las plantas forestales para una variedad de sitios de reforestacion. Sin embargo, normalmente existe un pobre conocimiento sobre ellos. Con el fin de usar los FEC en forma exitosa se deben considerar su formulacion, el patron de entrega y sus interacciones ambientales. Este trabajo sintetiza los distintos tipos de FEC (organicos, productos con nitrogeno de lenta solubilidad y productos recubiertos) y diversas investigaciones asociadas a su utilizacion. Ademas, revisa las ventajas y desventajas asociadas a los FEC, se realizan ciertas recomendaciones sobre su utilizacion y menciona algunos de los desafios para futuras investigaciones destinadas a mejorar la comprension en las formas de aplicar los FEC en situaciones forestales.

Effect of large and small herbivores on seed and seedling survival of Beilschmiedia miersii in central Chile

In the Mediterranean region of Chile, populations of the threatened tree Beilschmiedia miersii have been strongly affected by anthropic disturbances, causing...

CHEMICAL FRACTIONS OF Al IN VOLCANIC SOIL AMENDED WITH CELLULOSE WASTE

The cellulose industry generates a great volume of organic and inorganic waste, one of these wastes are called dreg (D) and grits (G). These residues have a high content of calcium carbonate, positioning them as potential bleachers in acid soils. Due to the important content of Al in the residues, a sequential extraction was done to establish the metal chemical fractions such as exchangeable, adsorbed, organic carbonated, and the ones associated to sulfurs, in incubated samples (2, 4, 8, and 32 days at 60oC) of an Andisol amended soil with Grits, Dregs + Grits and lime in 1, 2 and 3 ton/ha doses. The results revealed that there was a significant increase in the amount of Al in all fractions, in comparison to the control soil. On the other hand the incorporation of these residues through a Dregs (70%) + Grits (30%) mixture provoked a pH increase, always higher than the commercial lime. Finally, the Al present on amended soils was mostly distributed in the residual and carbonated chemical fractions, which would constitute less labile chemical forms to the soil-solution.