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Title: Effectiveness of eutrophication control by phosphorus reduction: development of the INCA-P model
Author: A. J. Wade
Author: K. Raat
Author: D. Butterfield
Author: P. G. Whitehead
Author: Environment Agency
Document Type: Monograph
Annotation: Environment Agency Project ID:EAPRJOUT_1062, Representation ID: 591, Object ID: 2335
This report is concerned with the development of the Integrated Catchments model of Phosphorus dynamics (INCA-P) and the provision of a model-based assessment of the phosphorus dynamics within three major UK river systems: the Ant (Norfolk), the Lugg (Powys, Herefordshire) and the Kennet (Wiltshire and Berkshire). These three systems are of interest because they represent regionally significant water resources, and provide contrasting upland and lowland systems impacted by both diffuse and point sources. To set up and calibrate the model, this study utilised data from both past and contemporary studies to describe the catchment hydrology, the phosphorus concentrations and ecology of the stream water, the land use distribution and land management practices within each river system. In all three river systems, the spatial and temporal variations in the observed stream water phosphorus and suspended sediment concentrations exhibit complex patterns and a highly heterogeneous response. These patterns represent the complex interaction between the factors and processes controlling the transport and retention of phosphorus within the land and in-stream phases, and the influence of point source inputs. INCA-P is an intermediate-complexity modelling tool and requires training to learn how to set up and apply it. There are some data costs associated with applying the model to a river system, though typically these will be less than £1,000. It is not envisaged that the model could be applied to assess the phosphorus budget at a national scale. Instead, the model would form part of a hierarchy of models in which steady-state models such as the Export Coefficient Method or the Phosphorus Indicators Tool would provide a national summary of phosphorus loss, and INCA-P would provide a detailed assessment of an individual catchment where a particular research or management question exists.
Publisher: Environment Agency
Subject Keywords: ModellingCatchment basinsPhosphorusRiversEutrophication
Geographic Keywords: NorfolkKennetPowys
Extent: 151
Total file downloads: 215

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