Final answer:
An impervious surface does not allow water penetration, altering the water cycle and environment. The percentage of impervious surfaces is much higher in built environments compared to natural ones, causing increased runoff, flooding, and ecosystem disruption.
Step-by-step explanation:
An impervious surface is a type of surface that does not allow water to penetrate, preventing infiltration into the soil. Examples include roads, parking lots, and buildings. The difference in the percentage of total impervious surfaces between natural environments and built environments can be significant. Natural environments, such as forests, grasslands, and wetlands, typically have low levels of impervious surfaces, often represented by the bare rock or tightly packed soil surfaces. On the other hand, built environments, which include urban and industrial areas, consist of much higher percentages of impervious surfaces due to infrastructure development.
In natural settings, the percentage of impervious surfaces may be negligible, as they primarily consist of permeable soils and vegetation. Built environments, however, can have impervious surface ratios exceeding 50-90% in some urban centers, vastly reducing the land's ability to absorb water. This change can lead to increased runoff, potential flooding, and a reduction in groundwater replenishment. The increase in impervious surfaces also contributes to environmental issues such as the urban heat island effect and ecosystem disruption.
Given the changing use of land for human activity, the amount of impervious surface area is an important consideration for environmental planning and sustainability efforts to mitigate adverse effects on water management and ecosystems.