TITLE : Does the concentration of nitrates in soil affect the concentration of nitrates in the  water  down stream?
 
TEAM 50
Deanie Anderson  (Oregon)  deanieha@open.org
Ronald Campbell  (South Dakota)  campy@iw.net 
Connie Cusick     (Montana)  
Mari Knutson  (Wash)  Knutsonm@lynden.wednet.edu
 Background:  When one sees cattle in a pasture, green grass on a golf course, and geese around a pond, one assumes that nitrates are present in the soil and water environments. 
 
Study Rationale:   Nitrate compounds are known to be highly soluble in water.  If they are present in the soil, they will dissolve in any water that is present.  The resulting nitrate ions will be highly mobile.  They will move downward into ground water areas or into adjacent streams.  It is the contention of our team that soils that are found to have high concentrations of nitrate, will have a positive effect on the concentration of nitrates found in the water downstream.
 

Hypothesis: There is a direct correlation between soil nitrate concentrations and adjacent downstream nitrate concentrations.

Materials and Equipment:
nitrogen soil test kit
nitrate water test kit
soil core borer
plastic  ziploc bags
distilled water
30 meter tape
metric ruler
map of local area

Procedure:  (Follow safety procedures)
1.   Using a map of available area, determine nine test sites with varying
      degrees of suspected nitrate loading.
2.   Designate each site with a number in data book.
3.   Go to designated test site.
4.   Select a location one meter from water's edge.
5.   Obtain soil sample at a depth of 10 centimeters using soil core borer.
6.   Test soil per Hach kit instructions.
7.   Record data for designated site.
8.   Select water test site thirty meters downstream from soil test site.
9.   Obtain water surface sample.
10. Test per kit instructions.
11. Record  data for designated site.
12. Repeat steps 3 through 1l for all remaining sites.
 
Test Kit Procedural Notes:
The Hach kit that was used tested for nitrogen, not nitrates. The following assumptions had to be made to convert to nitrates:  *1 acre is equivalent to 2,000,000 pounds of soil (kit reference) * ppm of nitrogen can be converted to ppm of nitrate by multiplying by 4.4. During nitrate analysis, two moles of nitrate ions are reduced to one mole of nitrogen.  The mass ratio of two moles of nitrate to one mole of nitrogen is 124/28 which equals 4.4.
 

Data Table:  Mercer County Samples
       site  (see links for site photos)                              nitrate conditions             
    no.  location                              water (ppm)                  soil  (ppm)               
 1.  Princeton -Quaker Rd.       * neg.   neg. 
 2.  Lawrenceville-Medical Ctr. stream         5   neg.
 3. Washington Xing Pk. Delaware River         0.5   neg. 
 4. Hopewell feeder stream         1 cloudy   22 
 5. Stonybrook Organic Pond-watershed area         neg.   neg. 
 6. Washington St. stream         3.5   22 
 7. Lake Carnegie-boat house         1   neg. 
 8. Raratan Canal-         2   neg. 
 9. Stonybrook at Princeton entrance         2.8   neg. 
*neg. means negligible finding  

Data Analysis:     
  
Note: Series 1 represents soil nitrate data, while Series 2 represents water nitrate data.
 
Conclusion: Our hypothesis was NOT supported by the data collected.

Error Analysis:
Nonspecific sites were used based on types of bodies of water rather than load sites.
Wet samples may have an impact.  Rain preceded samples 6-9. Soil samples were taken in wet
   soils with the exception of site 4 and site 6.
Pond site, although heavy with algae and goose feces, exhibited low nitrates which could be due
   to plant nitrate absorption.
 
Extension:  This project is repeatable in any region of the country by students at both middle school and high school levels. Schools in varying locations can exchange data.

Further extensions could address:
*Test the relationship between plant growth amounts and types relative to nitrate levels. Look
  for indicator plant types.
*Test for the relationship of dissolved oxygen to nitrate levels.
*Test for the relationship between nitrates levels and presumptive coliform levels. (test results)
*Test the nitrate content of soils with varying textures-clay, sandy.
*Test the nitrate content of soils that differ in moisture concentration.
*Test the nitrate content of soils which contain differing amounts of organic materials.
*Test for inorganic and organic nitrogen sources.

Standards: National Science Standards:   Select Chapter 6, Content Standards for grades 5-8 and 9-12.  Also check your individual district, county and state standards. For an example of coordinated standards between local ,district, two state levels and higher education levels contact deanieha@open.org.
 
 
References:
Field Manual for Water Quality Monitoring, Mitchell and Strapp,1996 pp. 60-62
  Stonybrook Millstone Watershed Assessment Guide
See link site references
Hach kit instructions
Inquest Kit instructions
See also Woodrow Wilson Environmental Science Projects under Nitrate Loading: 3, 11, 14, 20, 25, and 38

Acknowledgments:
John Sacco-computer
Phi Long-computer
Paul Burchard-computer
Project Green-supplies
Rutgers at Cook College-information
Woodrow Wilson National Fellowship Foundation Environmental Science Institute-NSF funding