Disturbance maintains alternative biome states.
Understanding the mechanisms controlling the distribution of biomes remains a challenge. Although tropical biome distribution has traditionally been explained by climate and soil, contrasting vegetation types often occur as mosaics with sharp boundaries under very similar environmental conditions. While evidence suggests that these biomes are alternative states, empirical broad-scale support to this hypothesis is still lacking. Using community-level field data and a novel resource-niche overlap approach, we show that, for a wide range of environmental conditions, fire feedbacks maintain savannas and forests as alternative biome states in both the Neotropics and the Afrotropics. In addition, wooded grasslands and savannas occurred as alternative grassy states in the Afrotropics, depending on the relative importance of fire and herbivory feedbacks. These results are consistent with landscape scale evidence and suggest that disturbance is a general factor driving and maintaining alternative biome states and vegetation mosaics in the tropics.
Department of Plant Biology, Functional Ecology Laboratory, Institute of Biology, University of Campinas - UNICAMP, P.O. Box 6109, 13083-970, Campinas, Brazil.
Vinícius de L
Vde L
Dantas
Department of Plant Biology, Functional Ecology Laboratory, Institute of Biology, University of Campinas - UNICAMP, P.O. Box 6109, 13083-970, Campinas, Brazil.|Center for Physical and Mathematical Sciences, Federal University of Santa Catarina, 88040-900, Santa Catarina, Brazil.
Marina
M
Hirota
Department of Plant Biology, Functional Ecology Laboratory, Institute of Biology, University of Campinas - UNICAMP, P.O. Box 6109, 13083-970, Campinas, Brazil.
Rafael S
RS
Oliveira
CIDE-CSIC, Ctra. Naquera Km. 4.5 (IVIA), Montcada, 46113, Valencia, Spain.
Juli G
JG
Pausas
D017954:Africa South of the Sahara; D000569:Americas; D005390:Fires; D065928:Forests; D005843:Geography; D065948:Grassland; D012987:Soil / Q000737:chemistry; D014197:Trees / Q000502:physiology; D014329:Tropical Climate
D012987:Soil
Cerrado; feedbacks; fire; forest; herbivory; mosaic; savanna; savanna-forest transition; thresholds; tropical