EROS Fall 2009 Meeting Minutes
Saratoga Springs, NY
October 6, 2009
CLAD-EROS Joint Meeting
N&S deposition maps redesign-
NADP QA Manager approached chairs of EROS and CLAD to discuss whether color
scheme should be modified.
--Recent maps, particularly SO4 and NO3, show large areas of green, suggesting that
deposition is now at “safe” level for ecosystems in those areas. However, very sensitive
ecosystems respond at very low deposition rates and may be harmed.
Issue-current color scale does not give fine detail at low/high ends.
--Recommendation was to refine detail at low/high ends of concentration and deposition
bins. Previously lows were <1.0 kg N/ha; the expanded color bin is now <0.5 kg N/ ha.
Previously high bin was <7 kg N/ ha; the new expanded color bin is 9 kg N/ ha. For SO4,
previously low bin was <1.0 kg S/ha and expanded bin now is 0.3 kg S/ha. CLAD and
EROS chairs met via conference call to discuss values to define low/high bins. There are
3 different maps (A=current, B= Expanded scale, C= expanded scale with blue bins and
refined low values).
--Blue bin (level at which minimal impact to ecosystem is expected).
--Proposal to create maps for total N and S with ueg/L for concentration eq/ha for
deposition since critical loads for acidity are often defined by total N and total S (S+N).
--Should these maps replace the old maps or supplement maps?
--Are values for low/high bins reasonable?
--Check with Ellen Porter for presentation so that we can add to the EROS records and
--Does urban vs. rural designation matter? Should maps include contours over the Great
Lakes? Official maps prior to 2008 have not been re-drawn to change to Criterion 4; if
maps are re-drawn, should new maps reflect change to Criterion 4 (collection efficiency
of >75%. High elevation sites were impacted by this).
Do we want to relate the isopleths maps to ecosystem impacts?
Are we expanding the low ends of the isopleths were the a