Final answer:
Meanders are naturally occurring bends in rivers or streams caused by the erosion of the outer curves and the deposition of sediment on the inner curves. This process is influenced by the river's volume, the sediment type, and the land's slope. Historical meander maps, like Harold Fisk's, show how rivers change paths over time due to these geological factors.
Step-by-step explanation:
What is a Meander in Geography?
A meander is a bend or a winding curve in a river or stream that develops naturally as the watercourse flows across a flat or gently sloping terrain. The process of meandering involves the river eroding sediment from the outer curve of each bend and depositing it on the inner curve where the water flow is slower. This process is known as the tendency to scour the outer bend of a river channel and deposit sediment on the inner bend. As a consequence, over time, the bends become more pronounced and the river takes on a winding course.
Figure 9.4 - A meander map from a section of the Mississippi River drafted in 1944 by Harold Fisk illustrates this concept well. It shows the historical path changes of the river, indicating how the river has meandered over time, carving out new channels and abandoning old ones. The geological phenomenon is a result of variables such as water volume, sediment type, and the slope of the land. For instance, as the river or stream flows away from the source, its channel widens and the current slows, increasing sedimentation. Additionally, the abiotic features like channel width and water speed vary along the length of the river, influencing the potential for meandering. Near the source, the river has a narrow channel with fast-moving water, whereas downstream areas have wider channels with slower-moving water that facilitate the formation of meanders.
These natural processes are crucial in shaping the landscapes through which streams and rivers flow and are a key aspect of studying river dynamics and stream evolution.