Posts Tagged ‘rotation cycles’

IUFROLAT III Session Highlights: Impacts of logging on biodiversity in tropical forests

Impacts of logging on carbon storage and biodiversity in tropical production forests of Latin America

Moderator: Plinio Sist, CIRAD-ES, France

Friday, 14 June 2013, 8:00-10:00 (Chirripó)

Find more information on the IUFRO Task Force on Biodiversity and Ecosystem Services at:

www.iufro.org/science/task-forces/biodiversity-ecosystem-services/

The session addressed the very important issue of the trade-offs between biomass harvest, carbon storage and biodiversity. Biomass harvest is negatively correlated with biomass storage and, in most cases, with biodiversity.

A key finding of the first presentation, which dealt with a permanent plot experiment in the Amazon, is that logging intensity affects biomass recovery rate and period. The study determined that increased logging intensity is ensued by increased recovery rate, but increases the recovery period.

Another presentation highlighted the effects of logging after 30 years on tree diameter, timber species and floristic diversity. Floristic diversity had recovered to the original state. Conversely, diameter distribution was less heterogeneous and tree species composition had shifted to pioneer and other light demanding species.

The role of individual big trees was also highlighted in a presentation. The study conducted in Pará, Amazon, found that selective logging caused a net biomass storage decrease. Moreover, selective logging creates instability in stands, which results in elevated natural mortality of individual big trees, even 8 years subsequent to logging.

Another presentation emphasised the role of disturbance regimes, showing data that El Nino decreased standing biomass more than logging; where mature stands suffered more damage than newly logged stands. Emphasis was placed on the importance of rotation cycles, as the risk of devastating disturbance regimes increased with increasing rotation periods.

Presentations in this session:

Is Tropical Forest Conservation through silviculture possible? The contribution of Tropical Production Forest Observatory Sentinel Landscape. (Plinio Sist, CIRAD-ES, France)

Thirty years after logging: Three species dynamics in the Tapajos National Forest, Eastern Amazon. (Ademir Ruschel, Embrapa Amazonia Oriental, Brazil

20 years forest dynamics study case in the Embrapa Acre Forest in Acre State, Brazilian Western Amazon. (Marcus d’Olivera)

La dinámica a largo plazo de la diversidad taxonómica y functional de especies leñosas en bosques lluviosos tropicales aprovechados y con tratamiento silvicultural en Costa Rica. (Bryan Finegan, CATIE, Costa Rica)

Post-logging biomass recovery: a pan-tropical analysis (J Putz, Alexander Shenkin)

IUFRO - The International Union of Forest Research Organizations