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Conceptual model of sedimentgraph from flood events in a small agricultural watershed

100%

Banasik K., Mitchell J. K.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2008

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tom 39

A procedure for predicting the sediment graph (i.e. the suspended sediment flux), from a small river catchment by heavy rainfall, has been developed using the concept of an instantaneous unit hydrograph (IUH) and dimensionless sediment concentration distribution (DSCD). A formula for instantaneous unit sedimentgraph (IUSG) is presented, and a procedure for estimating the sediment routing coefficient, which is a key parameter of the IUSG, based on measured data of rainfall-runoff-suspended sediment is applied. Field data from a small, fi eld sized agricultural basin, lacated in center of Illinois has been used for analizing lag times for runoff (LAG) and sediment yield (LAGs). Assumptions about sediment generated during rainfall events are discussed.

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Nutrient outputs from two agricultural watersheds

81%

Banasik K., Mitchell J. K., Walker S. E., Rudzka E.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1998

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tom 458

Results of three-year water quality monitoring programs carried out in two small, lowland agricultural watersheds of various fertilization level: the Upper Little Vermilion River (ULVR) located in Central Illinois and the Zagoż- dżonka River located in Central Poland, were analysed. Nitrate and orthophosphate concentrations and loads are presented and discussed in relation to meteorological conditions and hydrological responses of the watersheds. The watershed with intensive agricultural practice (ULVR) generates the runoff with higher concentrations of nutrients. Concentrations of the considered nutrients were, in the case of N-N03 about 7.1 times, and in the case of P-P04 about 1.6 times higher in the ULVR than concentrations in the Zagożdżonka River. Nitrate-nitrogen losses amount to a significant part (about 15%) of applied total nitrogen fertilization in the ULVR. High concentration of P-P04 in runoff from Zagożdżonka watershed has also been recorded.

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Nitrate losses under various nitrogen management systems

71%

Mitchell J. K., Walker S. E., Hirschi M. C., Cooke R. A. C., Banasik K.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1998

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tom 458

The effectiveness of nitrogen management systems in reducing the movement of nitrate in surface and sub-surface flow in the Little Vermilion River watershed is presented. Nitrate in sub-surface tile flow have been monitored for five years from fields with various tillage and cropping management practices. Water samples have also been obtained along the mainstream of the watershed. Concentrations of nitrate differed little among specific sampling locations along the river, but they definitely followed a seasonal cycle. Nitrate concentrations from the tile drains varied considerably between fields depending upon the management systems used, primarily based on the level of nitrogen fertilizer applied. The effect of the application of large amounts of nitrogen fertilizer, particularly as a pre-plant operation, is clearly shown in the nitrate-N concentrations from tile drains. The pre-plant anhydrous-N application systems with average nitrogen application of 100 kg/ha/yr. had a mean concentration of nitrate-N of 16.8 mg/L while the side-dress and manure application systems with average nitrogen application of 85 kg/ha/yr. had a mean concentration of nitrate-N of 9.8 mg/L. The mean concentration of nitrate-N from a permanent meadow field was 1.1 mg/L. Nitrate-N losses from cropped fields have ranged from 15 to 41 kg/ha/yr. depending upon the management system. Losses from the grassed system was 3.8 kg/ha/yr. and in the most upstream river station was 12 kg/ha/yr. of nitrate-N.

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Applicability of the SCS curve number method to tile-drained watersheds

61%

Walker S. E., Banasik K., Mitchell J. K., Northcott W. J., Yuan Y., Jiang N.

Annals of Warsaw Agricultural University. Land Reclamation

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2000

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tom 30

3-14

Ograniczanie wyników

2 Zeszyty Problemowe Postępów Nauk Rolniczych

1 Annals of Warsaw Agricultural University. Land Reclamation

1 Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

4 Banasik K.

4 Mitchell J. K.

3 Walker S. E.

1 Cooke R. A. C.

1 Hirschi M. C.

1 Jiang N.

1 Northcott W. J.

1 Rudzka E.

1 Yuan Y.

1 2008

1 2000

2 1998

Conceptual model of sedimentgraph from flood events in a small agricultural watershed

Nutrient outputs from two agricultural watersheds

Nitrate losses under various nitrogen management systems

Applicability of the SCS curve number method to tile-drained watersheds