What drainage pattern would develop on a limestone in a humid tropical environment?
That would be karst topography. As rain falls through the air, it picks up CO2. This combines with the water to produce carbonic acid. This is a weak acid, but is does allow water to dissolve the limestone. As the water sinks into cracks, it dissolves the stone opening the cracks to create caverns. If the roofs of the caverns get too thin they collapse to create sinkholes. Because of the network of caverns and sinkholes associated with these conditions, streams don’t usually flow vary far over the surface. They will usually flow into sinkholes. Such streams are called disappearing streams. If this process is allowed to go on long enough, the sinkholes will eventually merge as the entire roof of the caverns collapses. This creates solution valleys through which the streams will flow until sufficient cavern space opens up below the surface for the streams to once again disappear. These are all characteristics of karst topography. BTW, this type of topography will develop anywhere the sur
