On 28 October, Cheryl Fox (CFOX@mda-is.mda.um.edu) sent a message
asking about social, economic, and biological indicators of the effects
of transition from conventional to sustainable agriculture. Thomas Gitau
of Guelph (email@example.com) seconded Cheryl's interest in
indicators, particularly for application to small dairy farms in the
Cheryl didn't say where she is looking to apply the indicators
(on the farms themselves?, in surrounding ecosystems?, in the economies of
rural towns?), so the following may not apply, but someone may be interested.
Seems like there are quite a few groups trying to come up with good
indicators; I'm sure many folks on this list were also involved in the
electonic conference on indicators of sustainability that took place
this spring, sponsored by SANREM and INFORUM. Steve McCann of World
Resources Institute (firstname.lastname@example.org) has put together a set of descrip-
tions of programs doing indicator of sustainability. So far I don't know of
anyone who has a working set that they are completely happy with. If you do,
I work for North Carolina State University, but on a federal project
called the Environmental Monitoring and Assessment Program (EMAP).
EMAP has a component for each of the major types of natural
resources in the country: agricultural lands, rangelands, forests,
estuaries, surface waters, the Great Lakes, and landscape ecology.
There are also cross-cutting groups concerned with design and statistics,
logistics, methods, quality assurance, indicators, and so on.
The Agricultural Lands Resource Group (ARG) has been working for
the last five years or so to develop an indicator program for
the status and trends in the condition of the agricultural resource
in the U.S. We also hope we can get some clues as to it's future
sustainability. So far we are looking just at annually harvested
herbaceous croplands (basically field crops and hay). We recognize
the importance of the social and economic parts, but our mandate is
to look at ecological aspects.
We've done pilot projects in North Carolina (1992), Nebraska (1993),
and now in five mid-Atlantic states. Our report on the 1993 work has
just gone out for review. In these pilots we get information from
farmer interviews as well as soil samples. Both are collected by
enumerators working through the National Agricultural Statistics
The indicator categories we are working on right now are soil
quality, crop productivity, land use and landscape structure, and
insect diversity. A lot of very smart people have been working very
hard at defining soil quality and how to measure it. In our group
we are looking at some of the standard physical and chemical parameters
(organic matter, pH, cation exchange capacity, etc.) as well as trying to
get a handle on the biological state of the soil, primarily by looking
at nematode trophic groups (they don't all eat plants!). New indicators
are under consideration such as infiltration, aggregate stability, and
Within crop productivity, we are estimating nitrogen use efficiency at a
field level, as well as making comparisons of reported yields to expec-
tations based on past county averages or on crop growth models. The latter
show some promise for factoring the weather "noise" out of yield trends.
A particular interest of mine is whether or not crop rotation is being
practiced, and we have a couple of indices for that.
In the area of landscapes, we look at field size and crop diversity, as
well as the number, size, and uses of farm ponds. Except for a small
study on insect diversity in farm ponds, the work on insect indicators
is just getting started, with ants as the prototype.
My own two cents as far as the challenges of indicator development:
1) Pulling different measures together. Soils tell you one thing,
crops tell you another, landscapes another. How do you make it
all fit? Now multiply that by a factor of ten when you try to
integrate across different types of ecosystems. Even within an
indicator category, you have to figure out how to put the pieces
together. Two examples from here are a soils report card that
rates the physical, chemical, and biological components, and the
use of the Soil Rating for Plant Growth developed by the USDA Soil
2) Scale. Do you want to know if an individual farm will be sustainable?
or a field? or a state? or a region? How do you combine indicators
taken at different scales?
3) Statistical confidence. Have a good sampling frame and put confidence
intervals on your measurements. That's a strength of EMAP; we
put a lot of thought and effort into those issues.
4) Circularity. If you calibrate your indicators based on systems you
consider to be in good or bad condition (or sustainable vs. nonsustainable)
then why not just use the criteria you used to make the distinction
in the first place? Cost would be one reason. Of course your indicator
might be something you care about in and of itself, too.
If anyone wants to know more, they can contact me or my boss, Dr. Lee
Campbell, at email@example.com. Also, we'll have a few posters at
the upcoming Agronomy, Crops and Soils meetings in Seattle.
Cheryl, I'm glad to see the Minnesota Dept. of Ag. interested in this
subject. I am a U of M graduate (B.S. Agronomy 1984). If you
haven't already, I recommend talking to Dr. Don Weise there.
He is a professor of weed science and has been involved in a
state-level sustainable agriculture working group. I don't know
if they're doing anything with indicators.
I think Victor Borge said something like "prediction is difficult,
especially predicting the future." Good luck to us all.
Speaking for myself and not necessarily reflecting the views of North
Carolina State University or the Environmental Monitoring and Assessment
| MIKE MUNSTER |
<> EMAP-Agricultural Lands phone 919-515-3311 <>
| 1509 Varsity Dr. fax 919-515-3593 |
<> Raleigh, NC 27606 email firstname.lastname@example.org <>
| USA |