Soil aggregates control N cycling efficiency in long-term conventional and alternative cropping systems

Erratum to: Nutr Cycl Agroecosyst (2007) 79:45–58 DOI 10.1007/s10705-007-9094-6

Author would like to change the first paragraph appearing after the section Nitrous oxide emission measurements on p. 51 as follows:

A cropping system effect on N₂O–N emissions was found for two successive measurements taken after the second fertilization of the conventional plot. At the May gas sampling event, N₂O–N emissions from the conventional cropping system (16.6 g N ha⁻¹ day⁻¹) were greater than fluxes from both the low-input (4.0 g N ha⁻¹ day⁻¹) and organic (no N₂O–N flux) systems (p < 0.05; Fig. 4). Greater N₂O–N fluxes were also observed in the conventional system (13.5 g N ha⁻¹ day⁻¹) than in the low-input (no N₂O–N flux) and organic (1.1 g N ha⁻¹ day⁻¹) systems at the June sampling event (p < 0.05; Fig. 4). With a cumulative N₂O–N emission of 484.2 g N Mg N⁻¹ (normalized with the soil N level of the cropping system), the conventional rotation showed the highest cumulative flux of N₂O–N in comparison to the low-input (235.8 g N Mg N⁻¹) and organic (103.6 g N Mg N⁻¹) systems. Although greater than the organic system, cumulative N₂O-N fluxes from the conventional and low-input systems were not different (p<0.05; data not shown).

Author would also like to change Fig. 4 on page 53 to:

Fig. 4

Effects of cropping management on nitrous oxide (N₂O–N) emissions from the conventional, low-input, and organic maize–tomato rotations at the Center for Integrated Farming Systems site (Davis, CA, USA). Arrows indicate approximate timing of fertilization events, the termination of irrigation, and the maize harvest. The N₂O–N fluxes paired with a ‘*’ were significantly higher among the cropping systems, within that sampling event (p < 0.05)