『Summary
This study considers long-term records of the nature of water
colour and coincident water quality and quantity in order to test
hypotheses about increases in release of dissolved organic carbon
from peat soils across the northern hemisphere. The study focuses
upon the treatment ratio, i.e. the ratio of the amount of coagulant
dose required to the water colour of the incoming water, and compares
this ratio to possible explanatory variables: pH, conductivity,
water temperature, river flow and alkalinity. The study shows
that:
(i) The annual average increase in treatment ratio is just less
than 6.5% over a six year period.
(ii) There is a long-term increase in the treatment ratio that
is independent of changes in riverflow, pH, conductivity, water
temperature and alkalinity and so a real change in DOC composition
is occurring.
(iii) There is a seasonal cycle in treatment ratio that is also
independent of the available water and climate variables.
(iv) The upward trend in treatment ratio is declining with time
over the study period.
The observed trends in DOC composition are consistent with an
explanation of increasing DOC concentration and flux based upon
changes in flow and temperature but is not consistent with present
explanations based upon changes in atmospheric deposition or upon
drought unless the effect of the drought are short-lived (1-2
years).
Keywords: Peat; Water colour; Water treatment』
Introduction
Methods
Analysis of monthly averaged data
Results
Discussion
Conclusions
Acknowledgements
References