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