<abstract xmlns="http://www.w3.org/1999/xhtml"><p>This study is focused on water quality and quantity modelling in the Berze River basin located in the Zemgale region of Latvia. The contributing basin area of 872 km<sup>2</sup> is furthermore divided into 15 sub-basins designated according to the characteristics of hydrological network and water sampling programme. The river basin of interest is a spatially complex system with agricultural land and forests as two predominant land use types. Complexity of the system reflects in the discharge intensity and diffuse pollution of nitrogen compounds into the water bodies of the river basin. The presence of urban area has an impact as the load from the existing wastewater treatment plants consist up to 76 % of the total nitrogen load in the Berze River basin. Representative data sets of land cover, agricultural field data base for crop distribution analysis, estimation of crop management, soil type map, digital elevation model, drainage conditions, network of water bodies and point sources were used for the modelling procedures. The semi-distributed hydro chemical model HYPE has a setup to simulate discharge and nitrogen transfer. In order to make the model more robust and appropriate for the current study the data sets previously stated were classified by unifying similar spatially located polygons. The data layers were overlaid and 53 hydrological response units (SLCs) were created. Agricultural land consists of 48 SLCs with the details of soils, drainage conditions, crop types, and land management practices. Manual calibration procedure was applied to improve the performance of discharge simulation. Simulated discharge values showed good agreement with the observed values with the Nash-Sutcliffe efficiency of 0.82 and bias of −6.6 %. Manual calibration of parameters related to nitrogen leakage simulation was applied to test the most sensitive parameters.</p></abstract>

This study is focused on water quality and quantity modelling in the Berze River basin located in the Zemgale region of Latvia. The contributing basin area of 872 km2 is furthermore divided into 15 sub-basins designated according to the characteristics of hydrological network and water sampling programme. The river basin of interest is a spatially complex system with agricultural land and forests as two predominant land use types. Complexity of the system reflects in the discharge intensity and diffuse pollution of nitrogen compounds into the water bodies of the river basin. The presence of urban area has an impact as the load from the existing wastewater treatment plants consist up to 76 % of the total nitrogen load in the Berze River basin. Representative data sets of land cover, agricultural field data base for crop distribution analysis, estimation of crop management, soil type map, digital elevation model, drainage conditions, network of water bodies and point sources were used for the modelling procedures. The semi-distributed hydro chemical model HYPE has a setup to simulate discharge and nitrogen transfer. In order to make the model more robust and appropriate for the current study the data sets previously stated were classified by unifying similar spatially located polygons. The data layers were overlaid and 53 hydrological response units (SLCs) were created. Agricultural land consists of 48 SLCs with the details of soils, drainage conditions, crop types, and land management practices. Manual calibration procedure was applied to improve the performance of discharge simulation. Simulated discharge values showed good agreement with the observed values with the Nash-Sutcliffe efficiency of 0.82 and bias of −6.6 %. Manual calibration of parameters related to nitrogen leakage simulation was applied to test the most sensitive parameters.

Discharge and Nitrogen Transfer Modelling in the Berze River: A HYPE Setup and Calibration

Environmental and Climate Technologies

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

This study is focused on water quality and quantity modelling in the Berze River basin located in the Zemgale region of Latvia. The contributing basin area of...

Discharge and Nitrogen Transfer Modelling in the Berze River: A HYPE Setup and Calibration

Published Online: Jul 14, 2017

Page range: 51 - 64

DOI: https://doi.org/10.1515/rtuect-2017-0005

Keywords
Hydrological response units, HYPE model, calibration, discharge, nitrogen

© 2017 Riga Technical University

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Discharge and Nitrogen Transfer Modelling in the Berze River: A HYPE Setup and Calibration

Published Online: Jul 14, 2017

Page range: 51 - 64

DOI: https://doi.org/10.1515/rtuect-2017-0005

KeywordsHydrological response units, HYPE model, calibration, discharge, nitrogen

© 2017 Riga Technical University

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Hydrological response units, HYPE model, calibration, discharge, nitrogen