Correction of soil compaction using wood ash in safflower crop

Abstract

Soil compaction is a big limitation to food production in agriculture. Wood ash is an agro-industrial residue generated by the burning of biomass in boilers for energy production. It can be used as a corrective agent and fertilizer of the soil. In this context, the objective of this study was to evaluate the root system of safflower cultivated under bulk density levels and wood ash doses in dystrophic Oxisol. The experiment was conducted in a greenhouse with a randomized block design under a 5x5 factorial scheme composed of 5 wood ash doses (0, 8, 16, 24, 32 g dm-3) and 5 bulk density levels (1.0, 1.2, 1.4, 1.6, 1.8 Mg m-3) with 4 replicates. The soil was collected from 0-0.20 m depth layer. Later it was incubated with the respective wood ash doses. Each experimental unit consisted of a pot made of three PVC (polyvinyl chloride) rings, in which the layers of 0.1-0.2 m were compacted. At 75 days after emergence, the plants were cut, their roots washed and the volume and dry mass checked. The results were submitted to analysis of variance and subsequent regression test, both at 5% probability. Soil densities negatively influenced the root system development and culture of safflower. Application of wood ash doses of 20 to 24 g dm-3 significantly improved root development of plant.

Inorganic Fertilization at High N Rate Increased Olive Yield of a Rainfed Orchard but Reduced Soil Organic Matter in Comparison to Three Organic Amendments

“…The Ash + N treatment tended to show values that rarely stood out in comparison to the treatments of inorganic or organic fertilization, which seems in accordance with its initial composition. In general, bottom ashes are fertilizing materials that can be valued for their content in nutrients such as P, K, Ca or Mg [20][21][22], but which can also present toxicity problems as they may contain high levels of heavy metals, such as Cd, Cr or Pb [23][24][25][26]. In this study, neither aspect deserves to be highlighted, perhaps reflecting, once again, its initial mineral composition and the moderate rates in which it was applied.…”

“…Fly and bottom ashes from burnt wood biomass in thermal power plants are materials of varied elemental composition, but with potential to be used in agriculture. These fertilizing materials can contain high levels of some valuable nutrients, such as calcium, phosphorus, potassium and/or magnesium [20][21][22], but also high levels of heavy metals [23][24][25][26] Nonetheless, several studies have shown benefits in soil properties or in the growth of agricultural and forestry plants through the application of wood ash [27][28][29][30].…”