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 4

Harvested ley yields, clover contentand concentrations of N, P, and K.


Year

System CutNutrient concentrations (g 100 g DM−1)
Yield
(kg DM ha−1)
Clover1 (%)NPK
Means.e.2c3Means.e.c4Means.e.c5Means.e.cMeans.e.c

CM9630335a
Cut 1476517171.4b1.500.060.220.011.840.09
Cut 24865243102.4B1.480.09B0.280.021.980.14
OM18203319b    
Cut 14092218272.6a1.550.090.220.011.690.06
Yr 1Cut 24111248454.7A2.240.05A0.310.022.100.10
OM28342278b    
Cut 14099194272.4a1.610.100.240.0161.680.11
Cut 24243228405.0A2.160.16A0.320.012.020.08
LSD671012n.s.n.s.n.s.
LSD7110.45n.s.n.s.

CM11021304a    
Cut 16269180112.1b1.570.040.240.011.990.08a
Cut 24752233112.1A1.460.06B0.270.021.820.09
OM19542264b    
Yr 2Cut 15453188342.5a1.640.110.220.011.650.06b
Cut 24089201423.6B2.190.04A0.300.011.760.07
OM29586312b    
Cut 15399209302.9a1.640.100.250.011.690.06b
Cut 24187189362.5B2.220.13A0.300.011.840.05
LSD689210n.s.n.s.0.25
LSD7130.51n.s.n.s.

OM28651    
Yr 3Cut 15499169192.31.520.050.240.011.600.08
Cut 23151217242.82.110.060.310.011.650.09

1The proportion of legumes was determined visually before harvest.
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 (sum of two cuts) using LSD at the 5% level, where yields of the same crop not differing significantly between systems are denoted the same letter.
4Pairwise comparisons of clover content separate for each cut, where clover contents of the first cut not differing significantly between systems are denoted the same letter, whereas clover contents of the second cut not differing significantly between systems are denoted the same capital letter.
5Pairwise comparisons of nutrient concentrations separate for each cut, where concentrations of the first cut not differing significantly between systems are denoted the same letter, whereas concentrations of the second cut not differing significantly between systems are denoted the same capital letter.
6LSD values at 5% level for the total yields (sum of two cuts) and that for clover content and nutrient concentrations of first cut.
7LSD values at 5% level for clover content and nutrient concentrations of the second cut.