ISP LAB MIDTERM

How to find standard error

take the standard deviation and divide it by the square root of n

How to find variance

Square the standard deviation

How to find Standard Deviation

in calc go stat, edit L1 and then stat calc choose 1-Var Stats and its SX

What is Porosity 

The measure of empty space in a material or between the soil particles expressed as a percentage. 

What is Permeability

The ability of the soil to transmit gases, water, or air through its pores.

Clay

Has very small particles, meaning higher porosity because there are many pores and a lot of empty space but low permeability meaning it is slow to pass fluids through.

Sand

Has high porosity, meaning there are many pores and lots of spaces and also has high permeability because there is a lot of space to pass things through meaning fast infiltration. 

Compact tight soil

Has lower porosity because the space is so tightly packed together

infiltration

the process of water flowing through 

silt

medium permeability and moderate infiltration.

Geosphere

solid parts of the earth: rock, soil,

Hydrosphere

All water

Atmosphere

gases around the earth

Biosphere

All living organisms

Turbidity

measure of how cloudy or murky water is due to suspended particles like sediment or algae

High turbidity

very cloudy. poor quality. 

Biotic index

measures water quality based on macroinvertebrates in the waters. 

High BI means 

Poor water quality with heavy pollution 

Low BI means

Good quality water less pollution.

Scatter plot

Use when trying to determine if there is a relationship between variables. R-squared shows how strong or weak the correlation is, and the slope shows if the relationship is positive or negative. 

Bar graph/Column graph

Use when you want to compare things

What are standard error bars

They represent the uncertainty or the variablity in a measure. Basically how reliable the data is. Long bars mean that the data varies more and there is not a lot of data samples. short bars mean that there are a lot of data samples so the data is more reliable. TELLS US IF HYPOTHESIS IS SUPPORTED OR NOT

How to find standard error bars

You subtract and add the standard error from the mean. To get the higher or upper you would add the standard error to the mean and to get the lower you would subtract the standard error from the mean. 

How to interpret scatter plots  

Use the Y equation to support whether there is a positive increase or a negative, if one goes up, does the other also, or as one increases, does the other decrease. R value shows how strong or weak a relationship is. IF THE FIRST NUMBER IN y= is positive the slope is postive

How to interpret a column graph

See if standard error bars overlap or not. if the bars DO NOT OVERLAP THAT MEANS THERE IS A SIGNIFICANT DIFFERENCE. This can be determined by finding standard error bars for each and comparing numbers