Biodiversity-based Productivity: Foundation of Ecologically Sustainable Forestry
truffler1635 at my-deja.com
truffler1635 at my-deja.com
Sat Oct 7 11:00:34 EST 2000
In article <39DF2314.CC947980 at forestmeister.com>,
Joseph Zorzin <redoak at forestmeister.com> wrote:
> posted in alt.forestry
> The following article was in the latest issue of "Ecoforestry"
> journal published by the Ecoforestry Insitute of Canada. Their
> web site is http://ecoforestry.ca/. I have permission from the
> author to post it here.
> Biodiversity-based Productivity: Foundation of Ecologically
> Sustainable Forestry
> Ray Travers
> "One of the most fateful errors of our age is the belief that
> 'the problem of production' has been solved."
> E.F. Schumacher (1974)
> Recent experimental studies on whole ecosystems support what
> many ecologists and observant lay people have long suspected:
> the more species which live in a biologically diverse ecosystem,
> the higher its productivity, and the greater its resiliency and
> capacity to withstand insects, disease, drought and other forms
> of environmental stress. Since we depend on ecologically
> sustainable ecosystems to clean our water, enrich our soil,
> produce our food, fibre and the very air we breathe,
> biodiversity is clearly something that we ought not to
> systematically degrade through ill-conceived forest practices.
> These new studies have enormous policy and practical
> implications. Their findings are dismembering the rationale for
> plantation forest management, even as they promote building the
> institutional capacity to move quickly to ecoforestry. There is
> now little scientific, ecological, economic or social
> justification for perpetuating these outdated practices, because
> this new knowledge is removing the very underpinnings and
> justification behind zoning for intensive forest management,
> widespread use of clear-cutting and setting the allowable annual
> cut above the long-run, sustained yield.
> In plantation forestry, the destruction of biological diversity
> is seen as a necessary and unavoidable tradeoff to "enhance"
Up to this paragraph, I agree totally with this post. Ray has done an
excellent job in looking at the latest research.
However, I disagree, at least in part, with the last sentence. Since a
majority of the conifers in both Ray's and my area are similar (Western
redcedar, Western hemlock, Douglas fir, Sitka spruce, Ponderosa pine,
Lodgepole pine, etc), I'd like to make at least a partial case for
The majority of biodiversity in forests is known to be mycorrhizal fungi.
Upwards of 1,000 species can be found with a single tree species: Douglas
fir. (The total is not complete, because no one has catalogued many of
the soil-dwelling mycorrhiza which seldom produce visible sporocarps such
as truffles or mushrooms. Some estimates estimate Douglas fir may
associated with 3,000-5,000 species.)
The _only_ short-term method of determining these fungi conclusively is
in monocultural plantations. Why? Conifer roots spread so rapidly and are
so widespread that a fungus found 100-feet away from a 100-foot tree may
still be associated with it. In plantations, there are no other potential
hosts. Ergo, it can be assumed that fungi found in plantations are
mycorrhizal with an individual host tree.
Most of this basic research has yet to be done. We still don't know how
many fungi there are. New species are found monthly, if not daily. Only
20-30% of the estimated total fungi of the world have been estimated
described in science.
There is strong evidence pointing to a succession of mycorrhizal fungi as
individual trees or shrubs mature. Without knowing the progress of that
succession, cultivation of these fungi may be impossible.
Thousands of soil-building organisms are similarly associated with duff
under Douglas fir. These need study as well. When David Perry first
started identifying them, he estimated it would take a minimum of 15
years just to describe them. Consider: the recent BioBlitz in Oregon
found over 800 species in one day. David Perry found over 15 times that
total from one cubic food of soil under Douglas fir in the H.J. Andrews
Experimental forest in 1990.
Finally, the known mycorrhizal fungi which can currently be cultivated
(Boletes, Rhizopogons, Suillus, Hymenogasters, Thelophora, Pisolithus,
Scleroderma, Tuber, Barssia, Hysterangium, etc) are often species
specific with an individual tree. These fungi vary greatly with slope,
soil type, elevation, annual rainfall, snow fall (or temperature range),
and possibly other factors which have not been addressed to date. The
only way I am aware of to determine these factors is by having
monoculture plantations which are rather intensively studied. It is not
enough to study them for a year. Time is required. The results of such
study should dramatically increase the number of fungi which might be
cultivated, increasing forest resilience and long-term survival, as well
as resulting in faster growing, healthier forests.
Daniel B. Wheeler
Sent via Deja.com http://www.deja.com/
Before you buy.
More information about the Ag-forst