dear colleagues,
Please find enclosed a paper published in current biology by Rutishauser
et al. 2015, from our TmFO network that might interest you, particularly
those interested in tropical silviculture.
abstract:
While around 20% of the Amazonian forests has been cleared for pastures
and agriculture, one fourth of the remaining forests is dedicated to
wood production. Most of these production forests have been or will be
selectively harvested for commercial timber, but recent studies show
that even soon after logging, harvested stands retain much of their
tree-biomass carbon and biodiversity. We use a network of 79 permanent
sample plots (376 ha total) located at 10 sites across the Amazon Basin
to assess the main drivers of time-to-recovery of post-logging tree
carbon. Recovery time is of direct relevance to policies governing
management practices (i.e. allowable volumes cut and cutting cycle
lengths), and indirectly forest-based climate change mitigation
interventions. We found that the proportion of initial above-ground
carbon stock lost (i.e., trees harvested and destroyed by logging
operations) best predicted the time to recover initial carbon stocks. No
other variables tested contributed substantially to the prediction of
recovery times, despite the fact that the sampled plots span large
geographic and environmental gradients across the entire Amazon Basin.
These results reveal clear patterns that can clarify tradeoffs for
policy-makers and forest managers between short-term economics and
long-term carbon storage and hence climate regulation. Forest management
regulations vary among Amazonian countries, but generally set minimum
cutting cycles at 30-60 years, with harvests of 10- 30 m3 ha-1. While
these cutting cycles are generally insufficient to recover commercial
timber stocks, such harvest intensities require 7 and 21 years
respectively to recover their initial ACS, assuming ACS losses
proportional to harvested timber volumes.
cheers
--
Plinio Sist
Cirad-ES
Directeur-Director
UR (B&SEF) "Biens et Services des Ecosystèmes Forestiers tropicaux"
Coordinator of IUFRO 1.02.02 Ecology and silviculture of moist forests in the tropics
Campus International de Baillarguet, TA C-105/D
34398 Montpellier Cedex 5 France
Tél : +33 4 67 59 39 13
Tel.Portable/Mobile Phone: +33 786 3289 46
http://ur-bsef.cirad.fr/fr