Geodetic Mobile Survey Methods for Riverbank Erosion Observations

Rivers are relief features susceptible to change over time more than any other. Dynamic and intensity of those changes depend on a series of factors that have been a research topic for decades, all with the goal of predicting and/or preventing changes that have a negative effect on ecological and administrative systems alike. This is especially evident on big river systems. The topic of water course related erosion, being a phenomenon that changes the shape, position and flow of a water course, has not, to this day, been exhausted, primarily due to a myriad of factors directly and indirectly influencing the process. At the same time, determining the influence of each of those individual factors is not possible without the use of adequate measurement methods that allow fast acquisition of relevant data, based on witch correct conclusions can be made about individual processes. Emphasis on fast acquisition must be made here because rivers are dynamic bodies and the changes they cause are also relatively fast. Geodesy, including measuring techniques and methods that it uses, has experienced major development in the past decades. This has opened new possibilities for addressing those previously mentioned needs of river systems erosional processes and their research. Considering all of the above and supplementing with a fact that Danube is the largest and strongest river flowing through Croatia, it can be concluded that Danube is the one most interesting from the aspect of determining erosion phenomena frequency/intensity in Croatia. For acquiring relevant data in a relatively short time adequate survey methods need to be applied. Hence, Danube and its particularly interesting segments were selected for determining applicability of contactless mobile measurement solutions with the purpose of assessing those systems in determining and predicting erosional risks and cumulative rates.