The Role of Soil Organic Matter and Manures in Sustainable Nutrient Cycling - Sustainable Management of Soil Organic Matter - page 258

from 18 November 1997 until 23 January 1998 when flow stopped due
to a lack of rainfall. Samples were stored (2-4 C) until analysis, which

was usually within 48 h. DOC was measured, after filtering (0.45

°

m),
using a total OC analyser (model CA-10, Skalar Analytical B.V., De Breda,
The Netherlands). Total losses of DOC were calculated as the sum of the
products of weekly drainage volume and mean DOC concentrations.
The largest losses during this period were from the HNU plots, which
exported ~120 kg C ha −1 (Fig. 4.5.1a). This is greater than the range
reported by Hope et al . (1994) for annual OC export (i.e. 10-100 kg C ha −1
year −1 ), and which included both DOC and particulate OC. No animal
manures were applied during the year preceding this work, although several

µ

Fig. 4.5.1. Mean total DOC export from undrained (a) and drained (b) plots over 2 months.
See Table 4.5.1 for notation.