Morphology and land use of floodplains in the western part of Sandomierz Basin (southern Poland, Central Europe) in the Roman period

The Roman period settlement zone east of Kraków extends for 30 km along the Vistula river valley. Settlement was closely related to morphological-hydrological situations. Sites were located close to the terrace edge, between ecosystems of the loess terrace and the floodplain, with optimal conditions for multidirectional economic activities, both agricultural and non-agricultural. Moreover, loess terrace flats were very convenient for land communication (in contrast to the not easy accessible floodplain). The Vistula River served as a water route, while small creeks supplied water to inhabitants. Although the same natural resources were available for inhabitants, they were not utilized in the same way, related to different settlement models. In the Roman period (especially in the 3rd–4th cent. AD) an important role, apart from developed agriculture, was played by various non-agricultural activities. Settlement sites can be divided into two zones. According to results of the most recent wide-scale research, stable settlement also encompassed floodplains. Settlement in the Vistula valley and on the Raba alluvial fan was influenced by changing natural conditions. Subboreal deep (3–4 m) incision of the Vistula bed and channels of its tributaries resulted in development of a narrow lower floodplain. The incision also produced good drainage of the higher floodplain, occupying almost the whole valley bottom. The effects of frequent floods were limited to intensive shaping of the lower floodplain. On the higher level, flood waters filled oxbows and backswamps. The point bars and old meander belts remained unflooded and the settlement there was undisturbed. Beneficial for settlement in the floodplain was: abundance of grazing ground for cattle, access to oak wood used in buildings and other non-agricultural activities, and availability of material required in pottery production. Agricultural progress from introducing new improved tools enabled exploitation of more “difficult” fluvisols.People living on loess terraces used small streams existing under the terrace edge. In contrast, access to water for inhabitants of floodplains was more difficult, due to the lack of creeks and with relatively deeper water tables (incision of river beds and draining of higher floodplains). For that reason, inhabitants of “desert-like” floodplains had to dig wells.Stable and long-standing settlement on the loess terrace developed non-agricultural production, dependent on resources acquired from the floodplain (oak wood, good quality loams, and Miocene clay from the outcrops on river banks) used in pottery production. The Raba river valley in the vicinity of the workshops supplied materials of lower quality for pottery production.