Land and Water Land and Water Nathan Wells Grade 4Nathan Wells Grade 4

Greenfield Elementary School Greenfield Elementary School

Overview video Model – how Model – how

scientists represent scientists represent complex events to complex events to help understand them help understand them better better

Fresh water – about 2.8% of the world’s water

The Water Cycle – it’s a continuous – it’s a continuous process (Lesson 1 & 2)process (Lesson 1 & 2)

PrecipitationEvaporationCondensationWater cycle.html

The Water CycleThe Water Cycle

PrecipitationPrecipitation Clouds gather excess Clouds gather excess

waterwater Water falls back to earthWater falls back to earth

• HailHail

• RainRain

• SnowSnow

• SleetSleet

Drought – long periods Drought – long periods without precipitationwithout precipitation

The Water CycleThe Water Cycle

CondensationCondensation Water vapor risesWater vapor rises Cold air forms in the Cold air forms in the

atmosphereatmosphere Water vapor clings to Water vapor clings to

particles of dustparticles of dust Cold air turns droplets Cold air turns droplets

to particlesto particles Droplets combine to fo

rm clouds

The Water CycleThe Water Cycle

EvaporationEvaporation The sun heats the The sun heats the

earthearth Water changes to gas Water changes to gas

(water vapor)(water vapor) Minerals are left Minerals are left

behindbehind

Other related concepts…Other related concepts…

Transpiration – plants Transpiration – plants “sweat” or lose water “sweat” or lose water into the atmosphereinto the atmosphere

Hydrologist – Hydrologist – scientists who study scientists who study water on the earth water on the earth and in the and in the atmosphereatmosphere

Geologist – scientists Geologist – scientists who study landformswho study landforms

WatershedWatershed

Modeling RainModeling Rain

Precipitation – it goes Precipitation – it goes several placesseveral places surface waters surface waters

(streams, lakes, (streams, lakes, oceans, etc.)oceans, etc.)

the groundthe ground evaporates into water evaporates into water

vaporvapor Runoff of impervious Runoff of impervious

surfaces and saturated surfaces and saturated landland

Examining Earth Materials Examining Earth Materials (Lesson 5)(Lesson 5)

Two types of matterTwo types of matter Inorganic – weathered rock Inorganic – weathered rock

fragments; never alivefragments; never alive Organic – living and decaying plant Organic – living and decaying plant

and animal materialsand animal materials

Four Soil ComponentsFour Soil Components

Gravel Gravel InorganicInorganic Heaviest, biggest Heaviest, biggest

particlesparticles Colored - tan, white, Colored - tan, white,

brown, graybrown, gray Sinks in waterSinks in water

Four soil components continued…..Four soil components continued…..

SandSand InorganicInorganic Lighter than gravelLighter than gravel Grainy textureGrainy texture Colored – white, gray, Colored – white, gray,

tantan Clumps in waterClumps in water FloatsFloats

Four soil components continued…Four soil components continued…

ClayClay InorganicInorganic Lightest soil Lightest soil PowderyPowdery Orange-brownOrange-brown Suspends in waterSuspends in water

Four soil components Four soil components continued…….continued…….

Humus (top soil)Humus (top soil) OrganicOrganic Loose textureLoose texture Large and small Large and small

piecespieces Holds a lot of waterHolds a lot of water ClumpsClumps Floats, then sinksFloats, then sinks

Where Does Water Go?Where Does Water Go? (Lesson 6) (Lesson 6)

Water seeps into Water seeps into ground between soil ground between soil particles or particles or pore space under the force under the force of gravityof gravity

Pore space – space Pore space – space between soil particlesbetween soil particles

Gravity – force that Gravity – force that pulls matter to earthpulls matter to earth

Where Does Water Go?Where Does Water Go?

Impervious – layers of rock, water flows off Impervious – layers of rock, water flows off or around itor around it

Runoff – water that flows over landRunoff – water that flows over land Compaction – the degree to which soil Compaction – the degree to which soil

packs togetherpacks together

Water TableWater Table

Underground Underground boundary between boundary between zone of saturation zone of saturation (land filled with water) (land filled with water) and the zone of and the zone of aeration (land filled aeration (land filled with air and soil.)with air and soil.)

Investigating StreamsInvestigating Streams

Origin of streamsOrigin of streams Flowing water or precipitationFlowing water or precipitation Melting snow and iceMelting snow and ice Underground springsUnderground springs

• Water that flows out of cavities or caves Water that flows out of cavities or caves (aquifers)(aquifers)

• Groundwater dischargeGroundwater discharge

Investigating Streams continued….Investigating Streams continued….

Different forms of streams….. Different forms of streams….. Rivulets – tiny channels that form gulliesRivulets – tiny channels that form gullies Gullies – deeper channelsGullies – deeper channels Tributaries – small stream branchesTributaries – small stream branches Rivers – joined streams and tributariesRivers – joined streams and tributaries

Investigating Streams continued….Investigating Streams continued….

Parts of a stream channel (trunk)Parts of a stream channel (trunk) Head – top of streamHead – top of stream Delta – triangular –shaped landform created Delta – triangular –shaped landform created

by deposited sedimentby deposited sediment Mouth – where the bottom meets larger body Mouth – where the bottom meets larger body

of waterof water Floodplain – land left behind after flood waters Floodplain – land left behind after flood waters

drain (often covered after heavy rain flows)drain (often covered after heavy rain flows) Tributary – branches of streamTributary – branches of stream

Erosion & Deposition Erosion & Deposition (Lesson 7 & 8)(Lesson 7 & 8)

Aerial drawing – Aerial drawing – “bird’s eye view” ; “bird’s eye view” ; view of stream model view of stream model from abovefrom above

Velocity – the speed Velocity – the speed of water flowof water flow

Erosion & Deposition continued….Erosion & Deposition continued….

Weathering - the process Weathering - the process by which rocks break by which rocks break down into various earth down into various earth materials including soilmaterials including soil

Erosion – the wearing Erosion – the wearing away of landaway of land

WindWind WavesWaves Flowing water or Flowing water or

precipitationprecipitation GlaciersGlaciers

Erosion & Deposition continued….Erosion & Deposition continued….

Deposition – the soil Deposition – the soil which is moved by waterwhich is moved by water

Sediment – another way Sediment – another way to describe depositionto describe deposition

Suspension – when fine Suspension – when fine particles float in water particles float in water and do not dissolveand do not dissolve

Load – large amount of Load – large amount of sedimentsediment

Causes an overflow of Causes an overflow of waterwater

GlaciersGlaciers

Moving rivers of iceMoving rivers of ice Usually only moves a Usually only moves a

few inches a dayfew inches a day

Modeling Tributaries (Lesson 9)Modeling Tributaries (Lesson 9)

Stream trunk and its Stream trunk and its tributaries act as a tributaries act as a system for draining system for draining landland

Watershed – all of Watershed – all of surrounding area surrounding area drained by stream drained by stream channel and channel and tributariestributaries

Hills and Rocks: How Nature Changes the Hills and Rocks: How Nature Changes the Direction and Flow of Water? (Lesson 11)Direction and Flow of Water? (Lesson 11)

What Is An Oxbow Lake?What Is An Oxbow Lake? AAn oxbow is a n oxbow is a crescent-shaped lake lying alongside a crescent-shaped lake lying alongside a winding river. The oxbow lake is created winding river. The oxbow lake is created over time as erosion and deposits of soil over time as erosion and deposits of soil change the river's course. You can see change the river's course. You can see how an oxbow lake takes shape below:how an oxbow lake takes shape below:

Oxbow LakeOxbow Lake

Dams: How Humans Change the Dams: How Humans Change the Direction and Flow of Water Direction and Flow of Water

(Lesson 12)(Lesson 12) Flood-control dams – a barrier that Flood-control dams – a barrier that

controls the direction and flow of watercontrols the direction and flow of water Main purpose is to hold excess water from a Main purpose is to hold excess water from a

stormstorm Reservoir is an artificial lake created for Reservoir is an artificial lake created for

excessive runoffexcessive runoff Hydroelectric power – stored water Hydroelectric power – stored water

generates electricitygenerates electricity

““Dams” continuedDams” continued

Flood – caused by a severe storm which Flood – caused by a severe storm which can cause a stream to overflow its bankscan cause a stream to overflow its banks

Flash flood - sudden increase in runoff due Flash flood - sudden increase in runoff due to heavy flood of waterto heavy flood of water

Levee – high ridges along banks that Levee – high ridges along banks that prevents or minimize floodingprevents or minimize flooding

““Dams” continuedDams” continued

Ecosystem – environment in which plants Ecosystem – environment in which plants and animals live and interactand animals live and interact

Irrigation – brings water to farmland Irrigation – brings water to farmland through drainage channels that provides through drainage channels that provides water for growing cropswater for growing crops