Final answer:
Lakes and rivers typically form in topographic lows where groundwater surfaces, with the water table reflecting the contours of the landscape. Groundwater, in addition to providing flow for rivers, is a major source of fresh water from aquifers. The majority of Earth's freshwater is stored in glaciers and ice caps, although lakes and rivers are vital, accessible sources.
Step-by-step explanation:
Lakes and rivers are often found in topographic lows where groundwater is expressed as surface water. The relationship between groundwater and the topography is dynamic and interconnected. The water table, which is part of the groundwater system, typically mirrors the landscape's topography, rising with hills and descending into valleys, where it often emerges to form streams and lakes.
During periods of heavy rain, this water table receives recharge from precipitation that permeates into the ground. Moreover, groundwater contributes significantly to the flow of rivers and provides fresh water through aquifers for drinking and irrigation purposes. Lakes, such as those within the Great Lakes system, are critical reservoirs of freshwater and are replenished by surface runoff and groundwater discharge, though they may change size due to climatic variations.
It's important to recognize that the majority of fresh water on Earth is held in glaciers and ice caps, making them the largest reservoir of fresh water. This underscores the importance of surface water bodies like rivers and lakes, which are readily accessible sources for human use and are integrated within the planet's hydrological cycle through processes like runoff and groundwater discharge, shaping our environmental biology.