Population growth and increased land consumption per household jointly lead to increases in urban and other developed surfaces in watersheds. Increases in population often indicates increased land and resource consumption and reduction in natural and agricultural lands. Changes in land cover can include changes in extent of different types and appearance of new types in a watershed. Forest cover can increase with restoration or afforestation of previously agricultural or barren areas. Impervious cover includes any paved or developed surface that prevents surface water penetration into the ground.