Research Article

N, P, and K Budgets and Changes in Selected Topsoil Nutrients over 10 Years in a Long-Term Experiment with Conventional and Organic Crop Rotations

Table 3

Harvested yields of cereals and potatoes and their concentrations of N, P, and K.

CropSystemNutrient concentrations (g 100 g DM−1)
Yield1 (kg ha−1)NPK
Means.e.2c3Means.e.cMeans.e.cMeans.e.c

CA15450152a2.050.061a0.400.0250.390.008ab
CA25181148ab1.990.054ab0.400.0270.370.006b
OA2148125d1.680.034c0.410.0150.390.009ab
BarleyCM4865134b1.850.034bc0.390.0190.370.006b
OM13881130c1.770.035bc0.400.0190.400.003ab
OM24017153c1.940.042ab0.420.0200.410.006a
LSD3470.18n.s.0.02

CA15866260a2.070.0500.380.0200.370.006
OatsCA25264214a1.990.0590.390.0120.390.007
OA42618297b2.300.1550.430.0120.590.012
LSD944n.s.n.s.n.s.

CA15696217a2.250.0470.400.0230.400.002
CA25606252a2.300.0370.410.0180.390.008
WheatOA2494185d2.230.0700.450.0120.390.007
CM4900260b2.340.0440.420.0140.390.005
OM13719187c2.210.0780.420.0130.390.009
LSD574n.s.n.s.n.s.

CA194743281.200.0160.300.0041.450.047
PotatoesCA295353491.220.0380.280.0011.420.058
LSDn.s.n.s.n.s.n.s.

1Yields of cereals were corrected to a water content of 15%, whereas yields of potatoes are presented as DM.
2Standard error of means. Yield data were averaged for the years 2001–2010, whereas data on nutrient concentrations were averaged for the years 2006–2010.
3Pairwise comparisons of yields/nutrient concentrations using LSD at the 5% level, where yields/nutrient concentration of the same crop differing significantly between systems are denoted different letters. Nonsignificant comparisons are denoted n.s.
4In the organic system OA, oat was grown in a mixture with peas. Yields are given as the sum of the two crops, whereas nutrient concentrations are given as a weighted average (based on the DM weights of the two crops).