[PCA] QUESTION: Native Plant Habitats and Additional Nitrogen Gas (fwd)

[Olivia Kwong]

---------- Forwarded message ----------
Date: Thu, 4 Dec 2008 12:33:13 -0800
From: Wendi at Three Ravens Ranch <wendi at 3ravensranch.com>
To: Olivia Kwong <plant at plantconservation.org>
Subject: question for native plant  list

Hello Olivia,

Can you please post this question for botanists, plant biologists, ecology
or native plant specialists on the list?

I am researching the effects to native plant habitats of additional nitrogen
gas in the atmosphere when SCR emission control is used to comply with EPA
2010 NOx regulations. Would anyone have insight on this issue?

In order to comply with EPA 2010 regulations to reduce NOx emissions from
on-highway diesel engines many engine manufacturers will be using SCR
technology. SCR, or Selective Catalytic Reduction, uses Diesel Exhaust Fluid
(or urea) to covert harmful nitrogen oxides into nitrogen gas and water
vapor.

Advocates claim that SCR will reduce NOx emissions by up to 90%,
hydrocarbons (HC) and carbon monoxide (CO) emissions by 50-90% and
particulate matter (PM) emissions by 30-50%.

What effects will the increase in water vapor and nitrogen gas have on
ecosystem diversity and native plant survival? Can nitrogen availability be
a limiting factor for ecosystem vegetation dynamics?

Thank you,
Wendi Lutz
Three Ravens Ranch
http://www.3ravensranch.com