Why do mountain rivers stay relatively straight while rivers on the plains meander and curve? Oa. Mountain rivers have less of an incline, causing them to meander and curve less. Ob. Mountain rivers are constrained by hard bedrock. Oc. Mountain rivers are typically man-made drainage pathways for reservoirs and are engineered to be straight. Od. Rivers on the plains are typically colder in temperature, which causes them to erode their banks and meander at a quicker rate. What causes lowland rivers to meander? Oa. A small disturbance (such as a muskrat digging into the side of a stream) is exacerbated over time, causing the river to erode dirt from one side of the bank and deposit it on the other side. Over time, this causes meandering in the river. Ob. A lowland river is suddenly shifted upwards in elevation due to tectonic activity. As the river cuts downward back towards sea level, it incises the land and eventually drops below the original floodplain. Oc. Curves in a lowland river gradually get sharper as erosion and deposition occur. As the curves grow, they finally meet and the banks merge. The river follows the straighter path and cuts through to the other side, and the old curve is eventually cut off from the river. Od. A stream eventually flows into a larger body of water such as an ocean or lake, and the current expands in width at the mouth where the two bodies of water meet. This causes a reduction in flow velocity, which leads to the suspended sediments in the stream to settle and aggrade. What general statement regarding meanders is true? Oa. Small lowland streams typically do not have meanders. Ob. Mountain streams develop meanders at a faster rate. Oc. The length of a meander is around six times the width of the channel. Od. A river with a slower flow will meander faster than a river with a faster flow.