Improved logging Flashcards
Managing selective logging to better protect tropical biodiversity
Aims and learning outcomes
Define selective logging and its impacts
Identify management methods for reducing impacts on forest and wildlife
Detail conservation options to protect logged forests from conversion
Logged tropical forests
Over 400 Million hectares of tropical forest in permanent timber estate (e.g. Blaser et al. 2011 ITTO)
‘Selective logging’ in the tropics
Only large marketable trees cut
Effect of logging on biodiversity?
Species composition
IUCN Red-listed bird species
% of unlogged species persisting
Species composition differs
Edwards et al. (2011) Proceedings B
Once logged is more similar to unlogged than twice-logged
Red-listed birds decline
Not significant difference between once-logged and twice-logged but is less than unlogged
Most primary forest species persist
75%, in twice or once logged
Effect of logging on biodiversity?
Negatives
Changes species composition
Some species apparently extinct in landscape
Logging is harmful, re-logging magnifies harm
Positives
Substantial amount of biodiversity persists
Includes Red-listed species (e.g. orang utan)
Managing logging for biodiversity
Key issue is how to best manage logging of primary forests
Emergence of…
Market incentives (FSC, REDD+)
Regulation (e.g. Bolivia, Brazilian Amazon)
We need to understand how best to direct incentives or regulation
What is best approach for biodiversity?
Managing logging to reduce biodiversity losses
- Reduced impact logging
- Lower intensity logging
- Land-sharing vs land-sparing logging
Reduced Impact Logging (RIL)
Includes a host of strategies designed to:
Reduce damage to forest structure
Reduce release of carbon
Increase viability of timber harvest over time
Prerequisite for timber certification under Forest
Stewardship Council (FSC)
Access to lucrative Western markets (price premium 5-77% above uncertified timber)
Pre-harvest inventories
Comprehensive Harvest Plan
Identify, measure and geo-locate all:
harvestable species
Protected species
Protect a number of mature ‘seed’ trees
Pre-harvest preparation
Planned roads Straight Narrow To target trees Limits on log dumps Vine cutting
During harvest
Crews trained in directional felling & extraction
Use of big tracked vehicles
Does RIL reduce damage?
Lower residual damage in E. Kalimantan
Bertault & Sist 1997 Forest Ecology & Management
Similar number and volume of trees felled but fewer injured trees and dead trees and less skidding damage
Smaller area of skid trails, with better recovery
Biodiversity benefits of RIL?
Conducted a meta-analysis Compared species abundance changes between primary and CL or RIL 3,474 comparisons from 41 studies Birds, inverts, mammals & amphibians Bicknell et al. 2014 Current Biology
Lower intensity logging
Farming at lower intensity reduces losses
What about under logging?
Meta-analysis of relative species richness between primary and logged forest
98 comparisons from 48 studies
Birds, inverts, mammals & amphibians
Burivalova et al. 2014 Current Biology
“Mammals & amphibians would suffer a halving of species richness at logging intensities of 38 and 63 m3 ha-1, respectively”
Is lower intensity logging viable?
Would offer improved species retention…
But, also reduces timber yields
Could that increase demand for forest?
Also lacked studies of mammals and amphibians from SE Asia
logging intensities of >100 m3 ha-1
Plenty of mammals & amphibs (not quantified)
Land-sharing vs land-sparing logging
Lower intensity logging = less biodiversity loss, but less timber
What if must produce a set yield from a concession?
Map this issue onto the land-sharing vs land-sparing framework
Framework currently focused on agriculture (e.g. Phalan et al. 2011 Science)
The incentives required to produce either scenario are equal
So which scenario do we want for biodiversity protection?
Use our bird, dung beetle and ant data
All species and primary forest species
Data were sampled at transect levels in the three land-use types
Generate 1000 hypothetical communities for each scenario by resampling transects
-4 low yield vs 3 high yield+1 primary transects
Community level: calculate the overall species richness
Species level: calculate the abundances of each species separately
How many species ‘win’ under each scenario?
Edwards et al. 2014 Global Change Biology
Overall species richness
Land sparing is lower than land-sharing
Land sparing gives more winning species
Land-sharing vs land-sparing logging
How best to manage logging of primary forest for biodiversity? Land-sparing logging best Lesson: leave some primary forest Develop policy drivers for land-sparing Extend to other regions and services What happens after logging ceases?
Managing logging for biodiversity
Several ways of reducing biological harm, but…
Biggest threat is conversion of logged forests to farmland
Especially in over-logged forest
E.g., ~35 Mha logged forest in Indonesia
How best to prevent conversion of logged forests?
1) Conservation purchases
RSPB & Birdlife to protect Harapan forest
Primary or degraded forests?
Do degraded lands represent cost-effective conservation? (Fisher, Edwards et al. 2011 Conserv Lett)
Logging records from 300,000 ha of forest
Span first, second and clearance rotations
Net Present Value of timber
Vs. metrics of biodiversity value
Cost-effective conservation?
Cost-effective conservation?
Protecting twice-logged forest minimises cost, but retains much biodiversity
1 ha unlogged = 5 ha twice-logged
Protect meta-population dynamics, buffer primary forests & retain connectivity
Explore the relationship between timber profit & biodiversity in other regions
Understand the optimal balance between primary and logged forest purchasing
2) Carbon enhancements & REDD+
Carbon sequestered sold under REDD+
Liberation cutting of lianas and shrubs
Enrichment planting of diverse tree spp.
Important opportunity to restore biodiversity? OR destructive “carbon farming”? (Putz & Redford 2009 Global Env Ch) 11,000 ha forest restored since 1994 Two rounds of liberation cutting 1.2 million seedlings of 52 tree species Focus on birds Small recovery of species richness Minimal impact on composition
Species susceptible to logging
12 species declined after logging
7 are IUCN Red-listed
Susceptible species unaltered
Avifaunal trends
Recovery of:
Species richness
Insectivores
No difference in susceptible species
Reduction in:
Abundance
Frugivores
Loss of vine tangles for foraging/nesting?
Loss of fruits from vines & shrubs?
2) Carbon enhancement & REDD+
Bio-friendly mechanism for funding protection of degraded forest (Edwards et al. 2010b Conserv Lett)
Will intensively logged areas…
Regenerate to approximate a primary forest?
Remain in state of arrested succession?
Predict value of restoration for biodiversity vs costs of management
Summary
Logging is widespread & harms wildlife
RIL recover forest & stems biodiversity loss
Lower intensity logging protects more wildlife, but timber yields lower
Land-sparing with intensity logging & matched primary protection is best
Conservation purchases & carbon enhancements options to stop conversion
