Nevena Dragičević

Erosion Potential Method (Gavrilović Method) Sensitivity Analysis

In recent decades, various methods for erosion intensity and sediment production assessment have been developed. The necessity for better model performance has led to the more frequent application of the method sensitivity and uncertainty assessments in order to decrease errors that arise from the model concept and its main assumptions. The analysis presented in this paper refers to the application of the Gavrilovic method (Erosion Potential Method), an empirical and semi-quantitative method that can estimate the amount of sediment production and sediment transport as well as the erosion intensity and indicate the areas potentially threatened by erosion. The emphasis in this paper is given upon the method sensitivity analysis that has not previously been conducted for the Gavrilovic method. The sensitivity analysis was conducted for fourteen different parameters included in the method, all in relation to different model outputs. Each parameter was perceived and discussed individually in relation to its effect upon the method outputs, and ranked into categories depending on their influence on one or more model outputs. The objective of the analysis was to explore the constraints of the Gavrilovic method and the method response to changes deriving from the each individual parameter in an attempt to provide a better understanding of the method, the weight and the contribution of each parameter in the overall method. The parameters that could potentially be used in future research, for method modification and calibration in areas with different catchment characteristics (e.g. climate, geological, etc.) were identified. The most sensitive model parameters resulting from conducted sensitivity analysis for the Gavrilovic method are also those considered to be significant in the scientific literature on erosion. The Gavrilovic method sensitivity analysis has been done on a case study for the Dubracina catchment area, Croatia.

Pregled primjene Gavrilovićeve metode (metoda potencijala erozije)

A detailed review of application of the Gavrilović method (Erosion Potential Method) and its modifications, with a focus on the potential surface erosion, is presented in the paper, together with the guidelines and recommendations for future analysis and research as needed for physical planning and urban development. The Gavrilović method results are based on the source of information, expert experience, accuracy, and level of detail of the model input and output data. For further analysis, the authors propose investigation of additional sources of erosion materials, such as construction plots in expanding urban areas.

Modification of erosion potential method using climate and land cover parameters

Abstract The main focus in this article is given on the erosion potential method (EPM) modification. The aim was to provide a seasonal assessment, in addition to annual erosion assessment for the case study Dubračina catchment, Croatia. Seasonal assessment of erosion processes in the catchment will contribute to planning strategies that would benefit local community and enable the more appropriate and timely definition of erosion mitigation and protection measures. Original EPM was used for erosion intensity and sediment production assessment for two time periods: the past and the present time. The overall classification of erosion intensity categorises the erosion processes in the catchment as slight, although excessive erosion processes are present in some areas. For the method modification purpose, three main model parameters were changed: precipitation, soil protection coefficient and temperature. The greatest soil loss was found to occur in autumn, followed by summer, spring and winter period. The results indicated good erosion intensity and soil loss approximation obtained with the modified EPM and 13% soil loss deviation in comparison to the results obtained with original EPM. The erosion intensity, land cover map for both the present time and summer season and soil surface change over a two-year time period were verified.

Effect of Source-Varying Input Data on Erosion Potential Model Performance

Abstract This paper examines the performance of the Erosion Potential Method (EPM or Gavrilović) and the model response to input data variations caused by choosing different sources of information for the same parameter. The research presented addresses the input data uncertainty via an analysis of the two model input parameters (the soil protection coefficient and the soil erodibility coefficient). The parameter uncertainty analysis is performed following two different approaches: uncertainty analyses of both the selected sample size and the entire population are conducted for an erosion assessment case study of the Dubračina River catchment, Croatia. The analysis indicated that, when changing the data source, significant changes in the model outcome values can occur (up to 47% for this case study). Future method modifications should consider the mitigation of these two parameters by potentially making structural changes in the model and therefore moderating the effect.