How does erosion differ from weathering?

• Weathering  BREAKS  DOWN  the  Earth’s  material  into  sediments.  

•  Erosion  TRANSPORTS  the  sediments  to  a  new  loca?on.    

STOP:  What  are  the  2  different  types  of  weathering?  

4  Main  Agents  of  Erosion  

1. Water 2. Wind 3. Gravity 4. Ice

Erosion  isn’t  all  bad  though.  .  .  

Where  can  erosion  be  seen  in  real  life?  

• The  en=re  river  basin  in  Louisiana  is  the  product  of  sediment  deposi=on  from  the  Mississippi  River  (following  the  latest  rise  in  sea  level  about  5,000  years  ago.)    

One  possibility:  the  weathered  and  eroded  pieces  help  make  soil  

SOIL  

What  is  soil???  • Soil  is:  – The  upper  layer  of  earth  in  which  plants  grow,  a  black  or  brown  material  typically  consis?ng  of  a  mixture  of  organic  remains,  clay,  and  rock  par3cles  

Soil  Forma?on   •  As  rocks  are  broken  down  into  smaller  and  smaller  pieces  (weathering),  they  begin  to  break  down  into  soil  par=cles    •  Soil  is  a  mixture  of  rock  fragments,  organic  material,  air  and  water    

#6.1 Aim: What is the composition and importance of soil?

Agenda QOD (10)

Lesson:

Soil (15)

Activity: Soil Horizons (10)

Summary Share (5)

HW #18

Leaching = when minerals in the soil are dissolved and carried away

Erosion = movement of soil

Some terms to know…

Weathering = break-down of rock

#6.1 Aim: What is the composition and importance of soil?

Agenda QOD (10)

Lesson:

Soil (15)

Activity: Soil Horizons (10)

Summary Share (5)

HW #18

Soil is not just “dirt”

•  Weathered rock (~50%) •  Organic matter, living & dead (~5%)

•  Air

•  Water

Composition:

•  Soil  Composi?on  is:  • About  45%  weathered  rock  • About  5%  organic  maIer  (living  &  dead)  • Air  (25%)  • Water  (25%)  It  takes  100-­‐1,000  years  to  naturally  form  1  inch  of  soil!  

Good  Soil  Quality:  

How  big  are  we  talking?  

Property Sand Silt Clay

Water holding Low Med-high High

Aeration Good Med Poor

Nutrient supplying Poor Med-high High

Pollutant Filtering Low Med High

Why is Soil Texture Important?

SOIL TEXTURE PRACTICE…

Which  one  will  water  flow  through  faster?  

Why  do  we  aerate  our  lawns?  

So  that  plants  can  get  the  nutrients  they  need  

to  grow!  

Soil:  What  is  it  good  for?  

Characteris?cs  of  soil:  Soil  Triangle  •  Find  the  point  where  all  3  lines  meet.    The  name  in  that  area  is  the  type  of  soil  present.  

1)  Find  30%  clay  

2)  Find  40%  silt  

3)  See  where  the  lines  meet,  double  check  by  finding  30%  sand  

What  kind  of  soil  is  30%  clay,  40%  

silt,  and  30%  sand?  

 

Characteris?cs  of  soil  •  Find  the  point  where  all  3  lines  meet.    The  name  in  that  area  is  the  type  of  soil  present.  

Example:  50%  clay,  30%  silt  and  20%  sand  is  _______________  

Exit Ticket 1.  What river formed the Grand

Canyon? 2.  What is the difference between

deposition and erosion? 3.  What are the 4 main agents of

erosion? 4.  Landslides are caused primarily

by which agent of erosion?