Karst landscapes are formed over time due to the chemical weathering and attrition of underlying limestone content. The chief culprit is acid rain, which produces carbonic acid, which dissolves the limestone content in the bedrock undrlying the soil. Karst landscapes are typified by an absence of vegetative growth, and almost barren appearance, and an absolute lack of ponds, streams, or other freshwater activity. The presence of sinkholes, while not always present, is another feature identifying karst landforms. The limestone constituent of the soil is dissoved, leaving the remaining soil particles to be washed away, which leaves a void in the ground. When the water level falls, the support mechanism for the soil on top is nonexistent, and the roof usually falls in, forming the sinkhole. The karst landscape can be a product of inefficient human management, but usually is the product of a natural weathering force on Earths surface.
Karst landforms are formed due to chemical weathering of rocks over the time. The most impacted rock is the limestone which dissloves when in contact with water/ acid.
The acid rain brings about the acids which wash over these rocks and causes the outer structure to dissolve, the inner rocks remain intact, and a circular/spherical shape is assumed by the rock. Usually leads to the formation of the plateaus.
The river water causes the limestone to dissolve and form an undulating surface, as that of plains. However, its most remarkable feature is the appearance of stratification. These plains are not suitable for agrarian purposes. Eg- Karst region of Serbia, and Montenegro.
The sea water causes irregular erosion, and leads to formation of holes, irregular shapes and steep sloped cliffs. Usually characterised by archs, and even small islands. These are not structurally strong, due to continued exposure to denudation agent. Eg- cliffs of Norway, Iceland.
The presence of salts in the water escalates the process, whereas the pure water slows it down.