Excess nutrients in surface waters, such as phosphorus (P) from agriculture,
result in poor water quality, with adverse effects on ecological health and
costs for remediation. However, understanding and prediction of P transfers
in catchments have been limited by inadequate data and over-parameterised
models with high uncertainty. We show that, with high temporal resolution
data, we are able to identify simple dynamic models that capture the P load
dynamics in three contrasting agricultural catchments in the UK. For a flashy
catchment, a linear, second-order (two pathways) model for discharge gave
high simulation efficiencies for short-term storm sequences and was useful in
highlighting uncertainties in out-of-bank flows. A model with non-linear
rainfall input was appropriate for predicting seasonal or annual cumulative P
loads where antecedent conditions affected the catchment response. For
second-order models, the time constant for the fast pathway varied between 2
and 15 h for all three catchments and for both discharge and P,
confirming that high temporal resolution data are necessary to capture the
dynamic responses in small catchments (10–50 km2). The models led to a
better understanding of the dominant nutrient transfer modes, which will be
helpful in determining phosphorus transfers following changes in
precipitation patterns in the future
Is data on this page outdated, violates copyrights or anything else? Report the problem now and we will take corresponding actions after reviewing your request.