1.I have added a grid to the map
2. Work inside the black line to determine the area of the DeadZone that has a Dissolved Oxygen (DO) amount of 2 ppm or less.Count the squares, use notability or some other app to mark thesquares within the zone. Record in the table below a tally of wholesquares, as well as estimates of three quarter squares, halfsquares and quarter squares covered by the colored area. Add thetotal number of full and partial squares to determine the areainside the black line. Nearly all organisms important to theecosystem perish within this boundary. This is the area where mostof the animals are either dead or absent.
3.Repeat the procedure from step b, but this time count the totalsquares that lie in the colored portion of the map that is outsidethe black line. This is the area of affected water. Some organismsimportant to the ecosystem are unable to survive here.
4.Each square of the grid represents a land area of 360 squaremiles. Calculate the total square miles for the region of the mapthat is ≤2ppm DO by multiplying your total squares by 75. Repeatfor the region of the map that is greater than 2 ppm DO but lessthan or equal to 5 ppm DO. Record your results in the tablebelow.
5.Finally, to determine the total area affected by reduceddissolved oxygen, add the calculated area from the two regions.This represents the area we refer to as hypoxic. Record yourresults in the table below:
DO ≤2ppm (Dead Zone)
DO 5≤ ppm but >2ppm (affected area outside dead zone)
Total Hypoxic Area
1.Calculate square miles of 1/4, 1/2 and 3/4 by the percent(e.g. 25 1/4 squares= 25*(360*.25)= 2250 sq miles
2.The value in the rightmost column of your table is in squaremiles. In order to better appreciate the scale of the dead zone,compare your value of the Total Hypoxic Zone to the areas of thestates listed below. Which state is closest in area to the area youdetermined for the Total Hypoxic Zone?
State Area in Miles2
New 9350 Hampshire
New Jersey 8721
Rhode Island 1545