Field testing a lime requirement test for Atlantic Canada, and effect of soil pH on nutrient uptake
2000
Warman, P.R. | Walsh, I.Y. | Rodd, A.V.
Four crops were grown in three soil types at four sites near Truro, Nova Scotia in 1998. Water pH measurements and the Adams-Evans (A-E) Lime Requirement Test (LRT) suggested amounts of limestone required to bring the soil pH to 6.5. However, to evaluate the accuracy of three LRT procedures (A-E, Shoemaker, McLean & Pratt, and Mehlich), a range of lime rates (0 to 12 MT/ha) was chosen for each crop at each site. Fertilizers were applied to each plot based on the present Nova Scotia Soil Test Recommendations. Whole plant or leaf tissue was sampled at Zadoks 77 (spring wheat), Zadoks 85 (barley), ear development (sweet corn) and at each of 7 cuttings of turfgrass. The tissue samples were digested and analyzed by ICP for up to 10 elements and by a CNS Analyzer for N. Soil samples were taken at the final harvest and the soil pH was determined. Lime applications increased the pH of all plots, proportional to the application rates, however, the relationship was not always linear. Of the three tests, the SMP LRT most closely estimated the amount of lime required to increase the soil pH to 6.5; the other two tests underestimated the lime requirement. In this paper, only data concerning barley tissue nutrient content and uptake was related to soil pH; nutrient uptake was highest at pH 6.12 following a 6 t ha-1 lime application. Another paper will describe how the lime applications affected the nutrient uptake of the other three crops.
显示更多 [+] 显示较少 [-]