Changes in the middle section of the Narew River (between Ostrołęka and Łomża) in view of natural factors and anthropogenic pressures

Contemporary and archive cartographic materials illustrating horizontal profile of the middle channel of the Narew River (between Ostrołęka and Łomża) were compared in the GeoMedia application. The results of the analysis revealed that natural and anthropogenic factors had not significantly contributed to changes in the channel profile over a period of two centuries. Narew is a meandering river, and its activity is associated with intensified erosion of right-bank bends and lateral movement along its flat-bed channel. The most noticeable changes include reduced area of oxbow lakes, mainly due to succession, and suburban settlement in floodplains that had been regarded as unfit for development in the 20th century.