Bj. Chambers et al., Predicting nitrogen availability and losses following application of organic manures to arable land: MANNER, SOIL USE M, 15(3), 1999, pp. 137-143
A decision support system to predict the plant availability of nitrogen (N)
following organic manure applications to land has been developed, drawing
together the latest UK research information on factors affecting manure N a
vailability and losses. The ADAS MANure Nitrogen Evaluation Routine (MANNER
) accounts for manure N analysis, ammonia volatilization, nitrate leaching
and mineralization of manure organic N. Only a few easily available inputs
are required to predict the amount of N volatilized or leached, and the fer
tilizer N value for the nest crop grown. Predictions from MANNER have been
evaluated by comparison with independently collected data from a range of e
xperimental studies where pig, cattle and poultry manures were applied to a
rable crops. Good agreement was found (r(2) 60-79%, P<0.001), confirming th
at MANNER can provide a reliable estimate of the fertilizer N value of farm
manures spread to arable land under a range of conditions.