The sheer ignorance that has
prevailed over forest management is slowly coming to an end but must naturally
take a long time. To start with,
ownership is a huge problem. A block of land owned and operated by an enlightened
operator able to eyeball each and every tree and patch of soil is the
ideal. I suspect six billion people is
not enough to do the job that needs to be done.
Yet we are slowly evolving toward just that ideal.
A patch of wild forest left to
its own devices is hardly the best answer.
Fallen material overcomes the understory and suppresses healthy growth
there. Burn out is often the only
solution and an unsatisfactory one at that.
Such a patch needs open accessible understory that is constantly thinned
with both wood fiber extraction and perhaps the production of waste chips to create
a well managed forest. There is human
effort but it is within our capabilities.
The precontact Indians did just that well in the Eastern Forests. They may have not built roads, but they built
open productive forests around their fields.
Reforestation research in Latin America
helps build better forests
by Staff Writers
A tropical forest is easy to cut down, but getting it back is another story. In a special issue of the
"Twenty years ago, we had almost no information about how to build
a forest," said Jefferson Hall, staff scientist at the Smithsonian and
lead editor of the new special issue of Forest
Ecology and Management. "People either planted one of four non-native
species-teak, pine, eucalyptus or acacia-or they used a trial-and-error process
with other species that was not always successful. Now we can be smart about
which trees we plant at a given site, and we understand much more about what
motivates land owners and rural farmers to put this know-how to work."
Forests keep water clean, control soil erosion, store carbon,
shelter animals and provide plants that offer pharmacological benefits. Forests
also contribute to global-scale economic activity in the form of ecosystem
services. The Agua Salud project in the Panama Canal watershed, funded by the
HSBC Climate Partnership and featured in the special issue, is a 700-hectare
experiment that examines the ecosystem services forests provide: water for
people and the Canal, carbon storage to
mitigate global warming and biodiversity protection in one of the crucial
biological corridors between North and South America.
"Native tropical forests are some of the richest storehouses on
earth," said Eldredge Bermingham, director of the Smithsonian Tropical
Research Institute. "Now the science behind tropical forest restoration is
at a level of sophistication that reforestation projects can be planned to
target multiple goals-to store carbon, manage water and conserve biodiversity,
buffer old-growth forests from destruction and provide a strong return on
investment."
Managing forests for ecosystem services requires tradeoffs. A hectare
of teak stores as much carbon as a native forest after 20 years, but will
shelter far less biodiversity. In the Agua Salud experiment researchers plant
mixtures of native species. Their data predict that some mixtures will surpass
the carbon-storage capability of teak and the ability to support other plants
and animals.
This juxtaposition suggests that while secondary forests may not store
as much aboveground carbon as carefully tended plantations, they do a better
job of maintaining soil carbon stocks.
The information highlights potential tradeoffs in ecosystem services with land
management and points the way to the next generation of ecosystem service
research.
Scientific information to guide reforestation is especially necessary
in a world where half of the tropical forests are secondary forests growing on
abandoned farm and pasture land.
The special issue summarizes results from more than 60 tree species
grown in Panama
at sites with different rainfall and soil types. Native trees often grow well
in forest-restoration projects because they are adapted to local conditions.
Amarillo (Terminalia amazonia), a tree species native to Panama and neighboring
countries, grows as well or better than teak on degraded agricultural soils in
wet areas yet is sold for the same value as teak in timber markets.
Cocobolo (Dalbergia retusa), a highly valuable wood, grows particularly
well in relation to other species on dry sites with relatively infertile soils.
Several articles provide guidelines for land managers as they weigh
environmental and economic factors in their decision making. In Latin America there is a critical mass of information
available to begin recreating forested landscapes intelligently.
The Ecology and Ecosystem Services of Native Trees: Implications for
reforestation and land restoration in Mesoamerica .
Forest Ecology and Management, Volume 261,
Issue 10, 15 May 2011
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