科研之友
微信
新浪微博
Facebook
分享链接
摘要
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 was not influenced by tillage system, which explains 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.
- 出版日期2014-4
