Methods of Ecosystem Analysis - Water


Sassafrass Calcium Diet




    How much of the calcium measured in Sassafrass #2 can have arrived at this tree from precipitation (at calculated levels of calcium concentration)?     

    Sassafrass #2 is 70 years old. Its crown can be approximated as a circle with an average diameter of 6.1 m. (See diagram below.) 
Tree images created by Erin Heitkamp
The Answer:
  • Area of canopy = area of circle w/average diameter of 6.1 m = 29.22 sq. m
  • Total volume of rain falling on canopy area = height of rain in a year x 29.22 sq. m = (46.73 in)(2.54 cm/in)(1 m/100 cm)(29.22 sq m) = 34.69 cubic m
  • Total amount of Ca in the rainfall = concentration x volume = (0.071 mg/L)(34.69 cu m)(100 cm/m)^3(1 mL/cc)(1 L/1000 mL) = 2462.85 mg/yr
  • Amount of Ca available to the tree (with same canopy size ) in 70 years = 70 x annual amount = 172.40 g
  • Amount of Ca measured in Sassafrass #2 by plant chemistry group = 323.14 g
Note: Ca concentration used in this calculation were taken from the weighted average for [Ca++] in open funnel precipitation.
 
 

||| Water Analysis Home ||| Totoket Mountain Home ||| FES519b Home |||