861 
'eraged over the 420 
l of the original dry 
with a 50% decrease 
eviously we showed 
l the fluorescence of 
ace techniques, such 
ad of assessing crop 
rosion. 
ts have not yet been 
¡ible use of the blue 
э assess crop residue 
solved fluorescence 
ossible to define the 
loubtedly, several of 
u la ted that these are 
ijugated compounds, 
ynthesis of the plant 
istituents of the blue 
ri changes occurring 
dead vegetation. 
6 7 8 
s 
ice spectra of wheat 
nation. The sample 
Figure 3. Changes in blue fluorescence 
(420-550 nm) of wheat residue as a function 
of change in sample weight during 
incubation. The samples were excited by 
340 nm radiation.. 
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