Availability and uptake of trace elements in a forage rotation under conservation and plough tillage

Abstract

After 14 years under conventional plough tillage (CT) or conservation minimum tillage (MT), the soil available Al, Fe, Mn, Cu and Zn (0-5, 5-15 and 15-30 cm layers) and their plant uptake were evaluated during two years in a ryegrass-maize forage rotation in NW Spain (temperate-humid region). The three-way ANOVA showed that trace element concentrations in soil were mainly influenced by sampling date, followed by soil depth and tillage system (35-73 %, 7-58 % and 3-11 % of variance explained, respectively). Excepting for Fe (CT) and Al (CT and MT), the elemental concentrations decreased with depth, the stratification being stronger under MT. For soil available Al, Fe, Mn and Cu, the concentrations were higher in CT than in MT (5-15 and 15-30 cm layers) or were not affected by tillage system (0-5 cm). In contrast, the available Zn contents were higher in MT than CT at the soil surface and did not differ in deeper layers. The concentration of Al, Fe and Cu in crops were not influenced by tillage system, which explain 22 % of Mn variance in maize (CT > MT in the more humid year) and 18 % of Zn variance in ryegrass (MT > CT in both years). However, in the summer crop (maize) the concentrations of Fe, Mn and Zn tended to be higher in MT than in CT under drought conditions, while the opposite was true in the year without water limitation. Therefore, under the studied conditions of climate, soil, tillage and crop rotation, little influence of tillage system on crop nutritive value would be expected. To minimize the potential deficiency of Zn (maize) and Cu (maize and ryegrass) on crop yields the inclusion of these micro-nutrients in fertilization schedule is recommended, as well as liming to alleviate Al toxicity on maize crops.

Nutrient concentration and yield of maize (Zea maysL.) after vetch (Vicia sativaL.) in conventional and reduced tillage systems

“…These results were consistent with Lipiec and Stepniewski (1995) who reported that K and its uptake generally decrease with increasing soil compaction. As Houx et al (2011) these authors did not find differences between tillage systems, but García-Marco et al (2014) showed that soils in plough have more Al than in reduced tillage. In this study, Al was slightly higher in CT and MT with 0.018 g kg 1 than in ST with 0.017 g kg 1 .…”

“…Rhoton (2000) and García-Marco et al (2014) also concluded that, Fe, Mn and Zn tented to be higher in reduced tillage than in plough tillage under drought year, while opposite was true in the year without water limitation. In this study, Fe could be due to the fact that, during rainfall deficit periods (from May through September), ST and CT improved soil water facilitates and nutrients uptake.…”

“…(Ozpinar and Ozpinar, 2014). Some authors found higher Fe in reduced tillage than plough (Houx et al, 2011;García-Marco et al, 2014), while other authors observed the opposite tendency (Lavado et al, 1999). The concentration of Fe in maize tissues was sufficient according to the results of authors (García-Marco et al, 2014) who reported that deficiencies occur when Fe of leaves was below 0.01-0.08 g kg 1 , while others reported that these range were between 0.01 and 0.20 g kg 1 (Benton-Jones, 1991).…”

“…Despite their economic advantages, little information is still available for these poor fertile soils (Ozpinar, 2006a;Ozpinar, 2006b) with low nutrient availability on reduced tillage effects in the soil-plant system under winter vetch-summer maize rotation. However, published studies on the effect of tillage on nutrients in plants are scarce (Lavado et al, 2001, Stanislawska-Clubiak andKorzeniowska, 2009), and the few available reports showed interactions between soil and plant (Houx et al, 2011;García-Marco et al, 2014). Some authors did not find differences in micronutrient concentrations between tillage systems (Westermann and Sojka, 1996), others reported higher concentration of manganeze and zinc in reduced tillage than plough tillage -Rueda et al, 2007;Loke et al, 2013), and the opposite tendency for iron and copper (Loke et al, 2013).…”

“…The concentration of organic matter and behaviour of nutrients largely depend on soil properties, which may be altered by soil tillage (Rhoton, 2000). Nutrients, especially micronutrients, are affected by soil pH when they are decreasing with increasing pH (Lavado et al, 1999;García-Marco et al, 2014). Roots are a fundamental component of function to maintain the supply of nutrients and water to the plant because of a bridge between soil and plant aboveground.…”