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<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt">Dear colleagues, </SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt"></SPAN> </P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt">I am sending you this message on behalf of two Environment Canada research scientists, Jean-Sébastien Landry and Yves Bourasse, but please respond to me at <A href="mailto:Bruno@treecanada.ca">Bruno@treecanada.ca</A>. Thanks!</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt"></SPAN> </P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt">==============</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt"></SPAN> </P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt">We are considering developing a model to quantify the impact of ozone on the benefits provided by trees in urban areas, more specifically on their capacity to remove air pollution. This model would be used mainly to study hypothetical scenarios about future ozone levels and not for the assessment of the current benefits provided by urban trees.</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt"></SPAN> </P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt">The estimation of the benefits would probably be based on the Ufore model (</SPAN><A href="http://www.ufore.org/"><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt"><FONT color=#0000ff>http://www.ufore.org/</FONT></SPAN></A><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>) developed by the US Department of Agriculture. As for the impact of ozone, it would be based on exposure-response functions (ERFs) developed as part of the Aspen FACE experiment (</SPAN><A href="http://aspenface.mtu.edu/"><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA><FONT color=#0000ff>http://aspenface.mtu.edu/</FONT></SPAN></A><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>). Given our objectives and our current understanding of the
relationships between the different elements, here is what we would need. Of course, all of this does not have to come from a single source so do not hesitate to reply if you are only aware about one of the pieces.</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA></SPAN> </P>
<P><B><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>1. Tree inventory at the municipal level</SPAN></B><SPAN style="mso-ansi-language: FR-CA" lang=FR-CA><FONT size=3 face="Times New Roman"> </FONT></SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>We would first need tree inventory data consistent with the Ufore model requirements. This data has to come from field sampling. More details could be provided about the exact information that is required by the model, but here are the main elements (additional information about the sampling plots is required). </SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Tree species</SPAN><FONT size=3 face="Times New Roman"> <BR></FONT><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Diameter at breast height </SPAN><BR><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Height to base of live crown</SPAN><FONT size=3 face="Times New Roman"> <BR></FONT><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Total tree height</SPAN><FONT size=3 face="Times New Roman"> <BR></FONT><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Crown width</SPAN><FONT size=3 face="Times New Roman"> <BR></FONT><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Crown light
exposure</SPAN><FONT size=3 face="Times New Roman"> <BR></FONT><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Percent canopy missing</SPAN><FONT size=3 face="Times New Roman"> <BR></FONT><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- Crown dieback</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA></SPAN> </P>
<P><B><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>2. A model of tree growth in urban areas</SPAN></B><SPAN lang=FR-CA><FONT size=3 face="Times New Roman"> </FONT></SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>Since our ERFs are applied to the annual growth of trees and given that we are interested in the impact of ozone over many years, we would need some kind of "model" for the annual growth of trees in urban areas. This model would need to provide at least the aboveground volume (cu.m) of trees and their age. It could use all of the information coming from 1. above.</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA></SPAN> </P>
<P><B><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>3. Relationship between a change in aboveground volume and a change in leaf area</SPAN></B><SPAN lang=FR-CA><FONT size=3 face="Times New Roman"> </FONT></SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>Since our ERFs give the change in aboveground growth (in volume), we would need some relationship between such a change and a change in the leaf area (for deciduous and evergreen trees) because the air pollution removal in Ufore is based on the latter. Ideally, this relationship would be specific for trees in urban areas.</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA></SPAN> </P>
<P><B><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>Others</SPAN></B><SPAN lang=FR-CA><FONT size=3 face="Times New Roman"> </FONT></SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- If you are aware of a model that would directly allow us to quantify the impact of ozone on the benefits provided by trees in urban areas (mostly in terms of air pollution removal), do not hesitate to indicate this.</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA> </SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>- We could also be interested in doing something similar but based on particulate matter (PM) rather than ozone. We do not have ERFs for the impact of PM on tree growth though. If you are aware of elements that could be relevant for us in this regard, it would be appreciated.</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA></SPAN> </P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>==============</SPAN></P>
<P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA></SPAN> </P><SPAN style="FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 10pt; mso-ansi-language: FR-CA" lang=FR-CA>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #244061"><FONT size=3><FONT face=Calibri>Bruno Chicoine<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></FONT></FONT></SPAN></P>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #943634; FONT-SIZE: 8pt"><FONT face=Calibri>Project Manager, Tree Canada<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #943634; FONT-SIZE: 8pt"><FONT face=Calibri>402 - 222 Somerset St. West,<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #943634; FONT-SIZE: 8pt"><FONT face=Calibri>Ottawa, ON, K2P 2G3<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #943634; FONT-SIZE: 8pt; mso-ansi-language: FR-CA" lang=FR-CA><FONT face=Calibri>Phone: 613.567.5545 (225)<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #943634; FONT-SIZE: 8pt; mso-ansi-language: FR-CA" lang=FR-CA><FONT face=Calibri>Fax: 613.567.5270<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0cm 0cm 0pt" class=MsoNormal><SPAN style="COLOR: #943634; FONT-SIZE: 8pt; mso-ansi-language: FR-CA" lang=FR-CA><A href="http://www.treecanada.ca/"><FONT color=#800080 face=Calibri>www.TreeCanada.ca</FONT></A><o:p></o:p></SPAN></P>
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