Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - A method of computing uncertain nitrogen and phosphorus loads in a small stream from an agricultural catchment using continuous monitoring data
AU - Kulasova, A.
AU - Smith, P. J.
AU - Beven, K. J.
AU - Blazkova, S. D.
AU - Hlavacek, J.
PY - 2012/8/21
Y1 - 2012/8/21
N2 - A method for computing loads of total phosphorus and nitrate from a small catchment in the Czech Republic has been presented, given continuous measurements of water levels, turbidity and an ion-specific NO3--N probe together with a limited number of discharge measurements and analyses of grab samples. Given the observed variability in the observations, log-log regressions are used to convert water levels to discharge and to derive continuous estimates of total phosphorus and nitrate. Integrations to estimate loads using predicted values of the true discharges and concentrations are then carried out by a Monte Carlo method to avoid strong assumptions of independence and distribution. Coefficients of variation for the estimated monthly loads range from 5% to 23% for TP and 12-36% for NO3--N. At the annual time scales, coefficients of variation are of the order of 5% for both TP and NO3--N. The variability in the estimated annual loads between the years was, however, significantly larger than the uncertainties estimated within each year. (c) 2012 Elsevier B.V. All rights reserved.
AB - A method for computing loads of total phosphorus and nitrate from a small catchment in the Czech Republic has been presented, given continuous measurements of water levels, turbidity and an ion-specific NO3--N probe together with a limited number of discharge measurements and analyses of grab samples. Given the observed variability in the observations, log-log regressions are used to convert water levels to discharge and to derive continuous estimates of total phosphorus and nitrate. Integrations to estimate loads using predicted values of the true discharges and concentrations are then carried out by a Monte Carlo method to avoid strong assumptions of independence and distribution. Coefficients of variation for the estimated monthly loads range from 5% to 23% for TP and 12-36% for NO3--N. At the annual time scales, coefficients of variation are of the order of 5% for both TP and NO3--N. The variability in the estimated annual loads between the years was, however, significantly larger than the uncertainties estimated within each year. (c) 2012 Elsevier B.V. All rights reserved.
KW - NUTRIENT LOADS
KW - SEDIMENT
KW - TRANSFERS
KW - Uncertainty estimation
KW - WATER-QUALITY DATA
KW - EVENT DYNAMICS
KW - Monte Carlo sampling
KW - RIVER
KW - FLUX
KW - Nutrient loads
KW - Rating curve
KW - RATING CURVES
KW - MODELS
KW - REGRESSION
U2 - 10.1016/j.jhydrol.2012.05.060
DO - 10.1016/j.jhydrol.2012.05.060
M3 - Journal article
VL - 458-459
SP - 1
EP - 8
JO - Journal of Hydrology
JF - Journal of Hydrology
SN - 0022-1694
ER -