Date: Fri, 21 Sep 2001 14:55:50 -0400
To: Steven_Wofsy@harvard.edu, nacp@python.as.harvard.edu, nacp@io.harvard.edu
From: Michael Keller <michael.keller@unh.edu>
Subject: N2O
Cc: harriss@ucar.edu, Patrick.Crill@unh.edu, changsheng.li@unh.edu,
        rbirdsey@fs.fed.us

Dear Steve,

At the last minute in the workshop, you put up a note on "other gases/N2O."
 I'm not sure where this fits into the plan.  There are several linkages
for the N and C cycles.  For the N American situation Patrick and I see a
few prominent examples:

1.  Agricultural systems --  efforts to sequester carbon in agricultural
soils are balanced out in part by increases in N2O emissions (e.g.
Robertson et al. 2000; Science 289:1922-1925.  The same effect may occur in
fertilized forestry systems

2.  Animal husbandry systems - N2O emissions can increase where aeration of
waste is attempted to mitigate CH4

3.  N-Deposition effects may lead to increased forest growth (although
Caspersen says this is not so) in this case carbon sinks may also be offset
by N2O releases.

I'm not sure where this best fits in the current organization of the
document.  I think that perhaps when there is a more complete section on
land sources and sinks, we should note these relations.

- Michael
________________________________
Michael Keller
Visiting Research Professor
Complex Systems Research Center
Morse Hall
University of New Hampshire
Durham, NH  03824
USA

Voice +1 603 862 4193
Facsimile +1 603 862 0188

E-mail:  michael.keller@unh.edu