działalność rzek - baza erozyjna, terasy rzeczne

0:00 River erosion base 3:10 How river terraces are formed 4:07 Accumulation terraces 4:42 Erosion terraces 5:43 Accumulation-erosion terraces 7:35 River valley cross-section 7:40 Floodplain terrace 8:04 Floodplain/flood terrace 8:28 River bed 8:41 Relief-forming activity of rainwater 8:45 Rain ablation 9:15 Ravine 9:52 Earth pyramids