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Re: E-M:/ Deforestation, Dioxin, and NoCommercialLogging!-Reply -Reply -Reply

First and foremost, I have enjoyed these back and forths on the forest ecology, wood products and social dynamics of Michigan.  I would just offer the caution that email technology has a tendency to distort the perceptions we have of each other as individuals.   For the first time, it has allowed folks to expand their zones of communication to many others with widely differing views - a quality that has benefits as well as pitfalls.  Add to this the eternal conflict among humans for resources - one of the evolutionary forces that created big brains in humans (relative to other species in a brain to body weight ratio measure) and you have a recipe for potential disaster (virtual disaster, lets say). 
Nonetheless, the latest series of emails brings up some interesting issues regarding how we measure the status of the ecosystems we depend upon and exist within.  Often, measures used as surrogates for ecosystem characteristics of interest have relationships with those characteristics that are not what we assume them to be.  Ecological patterns that we observe are dependent upon the spatial and temporal scales of analysis; land managers, environmental researchers and environmentalists often fail to adequately address this issue and the result is less then optimal decision making.  At the same time, the units used to quantify ecological information (i.e. trees, forest acres, bundles of straw, biomass, mammals, scat, etc.) only provides a limited amount of information which may or may not be related ( in the way we assume them to be). 

For example, using biomass as a measure of system productivity tells us something about the amount of energy moving through the system (and other things).  However, it fails to tell us many other critical things about the system.  If we use these aggregate units (ie. indicators, surrogates, etc.) to make decisions, serious misunderstandings can and often do result.  Take forests for example.  Measuring the status of forest ecosystems (and associated ecosystems) by assessing the extent of the forest coverage (especially if the criteria for forest coverage is 10% tree cover) tells us relatively little about the status of this ecosystem type (although it is a relevant stat that has value as a component of many measures). 
The same can be said about the number of trees planted, the number of trees that exist on a site, etc. This sort of information only becomes useful for assessing the status of ecosystems when it is coupled with species-specific information.  (although it is valuable if one's focus is on maximizing yields - at least for the short term).  Without the species information, "diversity" is as easily made up of pileated woodpeckers, sandhill cranes, and brown creepers as it is of starlings, cowbirds and house sparrows and the resulting decision made using this information may be profoundly damaging to the environment (and economy and community strength).
For the Michigan forest discussion, it is important to recognize that a pound of feathers weighs the same as a pound of bricks, but they are fundamentally different in so many other ways.  The same can be said for "trees" or "mammals" or "biomass"........  So when the forest products industry tells us that there are more trees, we must ask what species they are, what combinations they occur in, where they are on the landscape and relative to other important ecosystem features, etc..  When government tells us that taxes are going down, we must look at the new "fees" we will be paying (ok, not the best analogy :)). 
Operationalizing this idea would be to ask questions like: "Of the new acreage of forest added to Michigan's landscape since 1980, what is the composition, particularly related to the proportion of yellow birch, hemlock, cedar, lowland hardwoods, forested wetlands, oak upland forests contiguous with extensive lowland forests and grasslands and savannahs?"  Then we need to ask whether these characteristics are such that they support the species and processes that we want.  Only then can we begin to assess the ecological impacts of the changes in forest cover and the dynamics of human impact on these systems. 
I also want to thank Alex and Sierra Club for hosting this forum.  
Have a happy Fourth of July!
David J. Zaber
----- Original Message -----
From: G. Tracy Mehan
To: Murphwild1@aol.com ; rmartin@envirolink.org ; enviro-mich@great-lakes.net ; 48MERDAV@menasha.com
Sent: Thursday, July 01, 1999 9:24 AM
Subject: Re: E-M:/ Deforestation, Dioxin, and NoCommercialLogging!-Reply -Reply -Reply

Enviro-Mich message from "G. Tracy  Mehan" <MEHANG@state.mi.us>

Thanks for that magisterial overview of Michigan forests.  Subscribers might also check out the State of the Great Lakes 1996 Annual Report(Office of the Great Lakes, MDEQ, April 1997), which features side-by-side articles by Dr. Henry Webster, former State Forester in Michigan and Project Director for the Lake States Regional Forest Resources Assessment for the The Lakes States Forestry Alliance(U. of MN), and Anne Woiwode, who needs no introduction to this crowd.  Check out your local library or call us at (517) 335-4056.  We may have a few extra copies on hand.

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