Surface Water Chapter 10, Section 2

Essential Questions Ch 10 Sec 2 What is a river system? What are the characteristics of ponds and lakes? What are three types of wetlands and why are they important?

Surface Water includes: Rivers Ponds Lakes Wetlands

Rivers Begin as small streams (often in mountains where snow melts and runs downhill) Terms Tributaries – streams and small rivers that feed into a main river Watersheds – the land surrounding a main river that feeds water to that river. AKA drainage basins Divides – a ridge of land that separates watersheds. The Continental Divide follows the line of the Rocky Mountains.

What is the largest watershed in the US? - Surface Water What is the largest watershed in the US?

- Surface Water

Sea Level and Streams

Rivers with Many Meanders

Ponds Bodies of fresh, still water Ponds are smaller and shallower than lakes. Sunlight usually reaches to the bottom of all parts of a pond. Plants usually grow on the bottom. Ponds form when water collects in low-lying areas of land.

- Surface Water Life in a Pond

Lakes Generally lakes are much deeper and bigger than ponds. Sunlight does not reach the bottom in a deep lake. Plants don’t grow on the bottom. Lakes can form naturally or can be man-made. Glaciers can cut through the Earth then melt (the Great Lakes) Crustal movements can cause deep valleys that fill with water (Lake Victoria in Africa) Volcanoes can erupt and block a river and form a lake Empty volcano craters can fill with water to become lakes People build dams across rivers to make lakes (for drinking water, irrigating fields, recreation). Lakes that store water for human use are called reservoirs

Wetlands A land area that is covered with water during part or all of the year Helps control floods and provides habitats for many species Three types of freshwater wetlands: Marshes – grassy areas covered by shallow water Swamps – look like flooded forests with trees and shrubs sprouting from the water; usually in warm, humid climates Bogs – contains mostly mosses because water is usually acidic; found in cooler northern areas; often formed in depressions left by melting ice sheets thousands of years ago Coastal wetlands contain both fresh and salt water Salt marshes – found along both coasts of the US; have tall, strong grasses Mangrove forests – found along the southeastern coast of the US; mangrove trees are short and have thick, tangled roots

Wetlands (continued) Name a famous swamp near us. The Okefenokee Swamp in south Georgia – translation from Indian: “Land of the Trembling Earth” Name a famous large wetland area south of us. The Everglades in south Florida. Wetlands naturally filter water and help control floods by absorbing extra runoff from heavy rains. Governments have passed laws to protect wetlands because of their value to Earth

- Wetland Environmentss Wetlands of Florida

Answers to Section 2 Essential Questions: What is a river system? All of the streams and small rivers that drain a watershed and flow into one main river make up a river system. What are the characteristics of ponds and lakes? Ponds are small and shallow with habitats from surface to bottom. Lakes are much larger and don’t usually have habitats at the bottom due to lack of sunlight. What are three types of wetlands and why are they important? Marshes, swamps, and bogs are important because they help control floods by absorbing flood waters, they filter water to clean it, and offer habitats to many living things.