Liana cutting for restoring tropical forests: a rare palaeotropical trial
Marshall A.R; Coates M.A.; Archer J; Kivambe E; Mnendendo H
African Journal of Ecology
Liana growth following forest disturbance is threatening the tropical carbon sink by delaying or preventing recovery. Tree growth can be stimulated by liana cutting; however its applicability for conservation management remains uncertain particularly in Africa (the least-studied continent for ecological restoration) and against pervasive barriers such as wildfires. We conducted a small-scale trial to investigate tree sapling regeneration following liana cutting in a lowland African forest prone to low intensity wildfires. We employed a BACI design comprising eighteen 25 m2 plots of sapling trees in liana-infested areas. After 5 years of liana cutting we saw greater recruitment stem growth and net biomass. Wildfires caused 51% mortality and probably masked liana cutting influences on species and survival but may have encouraged stem recruitment through interaction with liana cutting. Incorporating our data into a first quantitative review of previous studies we found that tree growth recruitment and net growth rates were all consistently higher where lianas were either absent or removed (respectively: 80% 215% 633%; n = 14 3 4). Tree growth impacts were approximately equivalent across size-classes and continents. We give recommendations for improved plot and sample sizes but conclude that liana cutting is a promising restoration method for lowland tropical forests including Africa.