🚀 go-pugleaf

Weizing Zhu wrote to mention that there is more to the persistence of
coastal pine forests than fire regime.  Let me add that coastal pine
forests probably persist on the Caribbean coast of Central America for
similar reasons.  When I compared maps of Holdridge lifezones and actual
land cover for Honduras (which has a long expanse of coastal pines) I
found pines occupying areas that would otherwise be considered "lowland
broadleaf evergreen forest".  The mismatch can be attributed to the
distribution of soils.  When I compared the map of land cover with soil
type and hydrology, the match was much more clear.  Soils play an
important role in determining the distribution of coastal pine forest in
Honduras.  And even though the area is periodically burned to maintain its
usefullness for pasture, the use of fire is probably a function of the
pines ability to withstand periodic exposure to fire more so than a matter
of the pines living there because of fire.  Still, the relationship
between coastal pines and fire is strong, especially considering the
ability of periodic burning to "reset" succession.  As a result, periodic
fire may also function in maintaining soil type, by preventing the
accumulation of organic matter for instance.  In one view therefore, pines
exist because of soil characteristics and not fire.  In a longer term view
however, pines may continue to persist because fire prevents establishment
of other species by not only killing off seedlings, but by maintaining
soil type.



On Fri, 13 Feb 1998, {Weixing Zhu} wrote:

> Eastern deciduous forest covers almost all eastern area of North America.
> Text book (example, E.G Bolen 1998, Ecology of North America) usually claims
> that the persistence of the coastal pine forest is the result of fire. It is
> no doubt that pines are more resistent to fire than the competing oaks. But
> without fire, will costal pine forest be replaced by decidous forest? Some
> oaks certainly may get in, but how about other deciduous species such as maple
> beech, and birch? Coastal plain is on very nutrient poor sandy soils. Annual
> nitrogen production in New Jersey Pine Barren is only 40 kg/ha. That is far
> below the normal range of 60-120 kg/ha in most deciduous forests. Indeed, fire
> is also the unavoidable result of low nutrient. It is low litter nutrient, not
> the low temperature, or low precipitation, which slows decomposition, and
> provides accumulated litter for fire.
> I would like to hear the comments on this issue.
>
> Weixing Zhu, postdoc
> Louis Calder Center
> Fordham University
> Armonk, NY 10504
>