1. The hyporheic zone has been shown to contribute colonists when surface flows recommence. 2. Because the limestone is very porous there are few surface flows of water. 3. The surfaces flow every which way, like a clown's elasticized smile. 4. The two main types of constructed wetlands are subsurface flow and surface flow wetlands. 5. The sub-surface flow has a strong seasonality with a minimal volume transport in winter. 6. Constructed wetlands are of two basic types : subsurface flow and surface flow wetlands. 7. So a surface flow of air from the poles to the equator is formed. 8. The entire area drains via surface flow which discharges through a replica arroyo section. 9. But just beneath the surface flows the darker undercurrent. 10. However, surface flow constructed wetlands may encourage mosquito breeding.