TY - JOUR
T1 - Understory bamboo flowering provides a very narrow light window of opportunity for canopy-tree recruitment in a neotropical forest of Misiones, Argentina
AU - Montti, Lía
AU - Campanello, Paula I.
AU - Gatti, M. Genoveva
AU - Blundo, Cecilia
AU - Austin, Amy T.
AU - Sala, Osvaldo
AU - Goldstein, Guillermo
N1 - Funding Information:
This research was funded by National Science Foundation-USA (grant number 02134174 ), Rufford Small Grant and CONICET (Argentina). We are grateful to F. Foletto, F. Silva, A. Izquierdo, M.F. Álvarez, S. Casertano, M. Villagra, M. Stamati, Agustin Paviolo and J. Garibaldi for their assistance in the field. We are also grateful to V. Marchesini and L. Vivanco for their help in the initial activities of the project and to Dr. H.R. Grau who made useful comments on the manuscript. Administración de Parques Nacionales (APN), CIES, DTRNEA, and Park rangers provided logistic support and facilities at the Iguazú National Park field sites.
PY - 2011/10/15
Y1 - 2011/10/15
N2 - Chusquea ramosissima is a native monocarpic bamboo species growing in subtropical forests of northeastern Argentina, which can dominate gaps and open forests in the region, particularly after human disturbance. This bamboo species started to flower in different areas of northeastern Argentina in 2001, with the flowering peak during 2002 and 2003 and small isolated flowering events still occurring until 2010. We studied the effects of C. ramosissima flowering and die-back on microclimate, litter decomposition, nutrient availability, sapling growth, abundance and regeneration of tree canopy species. We wanted to know how environmental conditions and ecosystem processes change through time after bamboo flowering and if bamboo die-back would favor regeneration of canopy trees. Twenty 50 × 50. m plots of flowering and non-flowering bamboo were permanently marked and vegetation dynamics as well as nutrient cycling and microclimate studies were performed. C. ramosissima die-back enhanced growth and reduced mortality rate of tree saplings during the first year after flowering. Only growth of tree saplings previously established was enhanced by the flowering event and tree-species richness and saplings abundance of canopy trees did not change as expected due to bamboo flowering. The short-term effect of tree saplings growth was likely due to incident solar radiation at the forest floor which doubled in the first year after the bamboo flowering event. Increased light availability at the forest floor simultaneously promoted the growth of other understory plants such as ferns, lianas and Piper spp. that rapidly colonized gaps and intercepted a percentage of the incident solar radiation after the first year, which together with an increased litter layer due to the senescence of the bamboo, may have inhibited establishment of new tree individuals and affected tree growth. Contrary to predictions, soil water, litter decomposition and soil nutrients were not significantly affected by bamboo flowering. Thus, successful tree regeneration in gaps following bamboo flowering appears to be restricted to a very narrow window of increased light availability (i.e., 1. year) before growth of other understory plants and rapid re-colonization of bamboo. Changes in resource availability, and the opportunity for overstory regeneration after bamboo flowering events appears to depend on climatic and community characteristics of the ecosystem where the flowering event occurs and also, on the flowering patterns and their synchronicity.
AB - Chusquea ramosissima is a native monocarpic bamboo species growing in subtropical forests of northeastern Argentina, which can dominate gaps and open forests in the region, particularly after human disturbance. This bamboo species started to flower in different areas of northeastern Argentina in 2001, with the flowering peak during 2002 and 2003 and small isolated flowering events still occurring until 2010. We studied the effects of C. ramosissima flowering and die-back on microclimate, litter decomposition, nutrient availability, sapling growth, abundance and regeneration of tree canopy species. We wanted to know how environmental conditions and ecosystem processes change through time after bamboo flowering and if bamboo die-back would favor regeneration of canopy trees. Twenty 50 × 50. m plots of flowering and non-flowering bamboo were permanently marked and vegetation dynamics as well as nutrient cycling and microclimate studies were performed. C. ramosissima die-back enhanced growth and reduced mortality rate of tree saplings during the first year after flowering. Only growth of tree saplings previously established was enhanced by the flowering event and tree-species richness and saplings abundance of canopy trees did not change as expected due to bamboo flowering. The short-term effect of tree saplings growth was likely due to incident solar radiation at the forest floor which doubled in the first year after the bamboo flowering event. Increased light availability at the forest floor simultaneously promoted the growth of other understory plants such as ferns, lianas and Piper spp. that rapidly colonized gaps and intercepted a percentage of the incident solar radiation after the first year, which together with an increased litter layer due to the senescence of the bamboo, may have inhibited establishment of new tree individuals and affected tree growth. Contrary to predictions, soil water, litter decomposition and soil nutrients were not significantly affected by bamboo flowering. Thus, successful tree regeneration in gaps following bamboo flowering appears to be restricted to a very narrow window of increased light availability (i.e., 1. year) before growth of other understory plants and rapid re-colonization of bamboo. Changes in resource availability, and the opportunity for overstory regeneration after bamboo flowering events appears to depend on climatic and community characteristics of the ecosystem where the flowering event occurs and also, on the flowering patterns and their synchronicity.
KW - Bamboo flowering
KW - Chusquea ramosissima
KW - Environmental changes
KW - Regeneration
KW - Semi-deciduous Atlantic Forest
KW - Soil nutrient dynamics
UR - http://www.scopus.com/inward/record.url?scp=80051828062&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80051828062&partnerID=8YFLogxK
U2 - 10.1016/j.foreco.2011.06.029
DO - 10.1016/j.foreco.2011.06.029
M3 - Article
AN - SCOPUS:80051828062
SN - 0378-1127
VL - 262
SP - 1360
EP - 1369
JO - Forest Ecology and Management
JF - Forest Ecology and Management
IS - 8
ER -