Soil compaction effect on black oat yield in Santa Catarina, Brazil

Abstract

Cultivated soils, when submitted to agricultural practices, tend to compact due to the pressure exerted by agricultural machines and implements, a process that compromises soil quality and system sustainability. Specific properties of each soil, such as particle size and organic matter content, interfere with the process and degree of compaction and, consequently, plant growth. This study aimed to analyze the effect of different degrees of compaction (DC) on soil physical properties and black oat (Avena strigosa Schreb) growth. For this purpose, four soils were collected: Latossolo Vermelho distrófico retrático (Ferralsol LV CN), Cambissolo Húmico alumínico típico (Cambisol CH LG), Nitossolo Bruno distrófico típico (Nitisol NB PA), and Nitossolo Bruno distrófico húmico (Nitisol NB SJ). They were submitted to five degrees of compaction (bulk densities corresponding to 80, 85, 90, 95, and 100 % DC), defined by their relation to the maximum density obtained by the Normal Proctor Test. For each DC, porosity, soil water retention curve, penetration resistance, hydraulic conductivity, and aeration capacity were determined. In a greenhouse, the oats were cultivated in the four soils with five different degrees of compaction. The experiment was carried out in a completely randomized design, factorial scheme, and five replications. Crop measurements included the growth rate, shoot dry matter, and forage quality analysis. Soil compaction changed the physical properties of soils. In all tested soils, macroporosity and total porosity decreased, more intensely at LV CN. It had macroporosity below the critical level (0.10 m 3 m-3) from DC 85. Hydraulic conductivity also decreased in all soils, which is evidence of significant environmental degradation from DC 90 onwards. Microporosity increased in the four soils due to compaction effect, and it is one of the reasons why permanent wilting point has increased. It resulted in a problem at NB SJ , mainly because it reduced the available water volume at DC 90, 95, and 100. Penetration resistance has also increased from DC 80 to 100 at all soils, exceeding the limit of 2 MPa in DC 80 for NB SJ , DC 85 for NB PA and LV CN , and DC 95 for CH LG , representing a risk to root development. Regarding black oat crop, there was a reduction in shoot dry matter only in Cambisol and in the higher DC, fiber content keeps within a satisfactory amount, without affecting forage quality in all soils and DC, thus showing that black oat is tolerant to compaction.

Chemical and physical attributes of five Oxisols as predictors of shoot dry mass of white oats

“…It is therefore important to know which soil attributes exert the greatest influence on the production of oats, thus helping in the management of the crop and in predicting its productivity. In a Cambissolo/Inceptisol in southern Brazil, Andognini et al (2020) noted decrease in the dry mass of black oats with increasing soil compaction. On the other hand, in a Latossolo Vermelho Distroférrico/Oxisol cultivated with soybean on a common-black oat straw, Balbinot Junior et al (2020) pointed out that oat root and shoot dry mass contributed to greater availability of water for soybean plants during water-deficit periods.…”

Crambe grain yield affected by compaction degrees of an Oxisol

“…Thus, the optimal compaction degree values for crops depend on the granulometric composition and soil structure (Suzuki et al, 2007;Andognini et al, 2020), and the magnitude of these values may vary over time depending on the climatic conditions, particularly the water availability and the crops involved (Hamza et al, 2005).…”

Physical-Hydraulic Attributes as Indicators of Functionality of Soil Pores Under Different Compaction Levels

“…In the perception of soil physical quality, changes in soil structural arrangement can reduce pore functionality, thereby maintaining physicalhydraulic processes essential to plant growth, especially water and air fluxes (ANDOGNINI et al, 2020).…”