2 Surface Water Movement Earth’s water supply is recycled
3 Surface Water Movement Runoff- water flowing down slope on earth’s surfaceVegetation allows for greater infiltration of water into the ground.Rate of precipitation can influence infiltration and runoff ratesSoil with high amounts of humus allow for greater infiltration.
4 Surface water movement Open soil pores and compaction will influence infiltration ratesGradual slopes allow for greater infiltration
5 Stream SystemsPrecipitation that does not enter the ground usually flows quickly across the ground and eventually collects into small channels. As the amount of run off increases the channels widen, deepen, and become longer.
6 Watersheds and Divides Watershed- all the land area whose water drains into a stream system.Divide- high land area that separates watersheds
7 Stream Load Stream load- all the materials carried by a stream Solution- dissolved material carried by water.
8 Stream LoadSuspension- particles held up by the turbulence of moving water.Varies with volume and velocity
9 Steam LoadBed Load- consist of sand, pebbles, cobbles that are too heavy to be suspended in the stream load. These materials may be “rolled” along the stream bed.
10 Stream VelocityThe ability of a stream to move material is dependent on the volume and velocity of water.Discharge is a measure of the volume of water in a streamDischarge = width x depth x velocity
12 FloodplainFloods occur when water spills over the sides of a stream channel.Floodplain- the broad flat area that extends out from a stream’s bank and is covered by water during flooding.
13 Stream DevelopmentSwift fast-moving water at high elevations carve a narrow pathway called a stream channel.The channel widens and deepens and is held in by the stream bank.
14 Stream DevelopmentStream activity erodes a path through sediment or rock.A “v-shaped” valley forms and the stream cuts down until it reaches base level- the level at which it enters another stream or body of water.After the stream cuts down then it starts to erode the sides of the stream bank and the valley becomes wider.
16 Stream DevelopmentMeandering streams-form in gradually sloped wide u-shaped valleys. As the stream passes through this valley it will erode the sides of the stream bank and start to meander (bend or curve).Water on the outside of a meander will flow quickly (erosion) and water on the inside of the meander will flow slowly (deposition).
21 Stream DevelopmentRejuvenation- stream activity resumes down cutting because of uplift or base level lowering.
22 Lakes and Freshwater Wetland Lakes- a depression in the surface materials of a landscape that collects and holds water.Fill with water from streams, runoff, precipitation, and springsForm from the movement of rivers (ox bow lakes), streams that become blocked, glacial remains.
23 Lakes undergo changeLakes will fill with sediment over time and become part of the local landscape because of deposition.
24 Lakes undergo changeEutrophication- process of lakes becoming rich in nutrients from the surrounding watershed changing the life that lives in the lake.
25 Freshwater WetlandsWetland- an area covered with water for a large part of the year.Bog- not stream fed, rich in moss, acidic soil,
26 WetlandsMarsh- occur along the mouth of streams and where extensive deltas occur, lush grasses, encourage wildlife
27 WetlandsSwamps- low lying areas near streams, shrubs and trees
28 Wetlands Importance of wetlands Destruction of wetlands Improve water qualityHabitat for migratory birdsDestruction of wetlandsFilled in for agriculture and urban growthFrom the US lost 50% of its wetlands to development