title: Effect of 7 yr of experimental drought on vegetation dynamics and biomass storage of an eastern Amazonian rainforest.
abstract: *At least one climate model predicts severe reductions of rainfall over Amazonia during this century. Long-term throughfall exclusion (TFE) experiments represent the best available means to investigate the resilience of the Amazon rainforest to such droughts. *Results are presented from a 7 yr TFE study at Caxiuanã National Forest, eastern Amazonia. We focus on the impacts of the drought on tree mortality, wood production and above-ground biomass. *Tree mortality in the TFE plot over the experimental period was 2.5% yr(-1), compared with 1.25% yr(-1) in a nearby control plot experiencing normal rainfall. Differences in stem mortality between plots were greatest in the largest (> 40 cm diameter at breast height (dbh)) size class (4.1% yr(-1) in the TFE and 1.4% yr(-1) in the control). Wood production in the TFE plot was c. 30% lower than in the control plot. Together, these changes resulted in a loss of 37.8 +/- 2.0 Mg carbon (C) ha(-1) in the TFE plot (2002-2008), compared with no change in the control. *These results are remarkably consistent with those from another TFE (at Tapajós National Forest), suggesting that eastern Amazonian forests may respond to prolonged drought in a predictable manner.
authors.affiliation: Universidade Federal do Pará, Centro de Geociências, Belém, Pará, Brazil.
authors.forename: Antonio Carlos Lola
authors.initials: AC
authors.lastname: da Costa
authors.forename: David
authors.initials: D
authors.lastname: Galbraith
authors.forename: Samuel
authors.initials: S
authors.lastname: Almeida
authors.forename: Bruno Takeshi Tanaka
authors.initials: BT
authors.lastname: Portela
authors.forename: Mauricio
authors.initials: M
authors.lastname: da Costa
authors.forename: João de Athaydes
authors.initials: Jde A
authors.lastname: Silva Junior
authors.forename: Alan P
authors.initials: AP
authors.lastname: Braga
authors.forename: Paulo H L
authors.initials: PH
authors.lastname: de Gonçalves
authors.forename: Alex A R
authors.initials: AA
authors.lastname: de Oliveira
authors.forename: Rosie
authors.initials: R
authors.lastname: Fisher
authors.forename: Oliver L
authors.initials: OL
authors.lastname: Phillips
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Metcalfe
authors.forename: Peter
authors.initials: P
authors.lastname: Levy
authors.forename: Patrick
authors.initials: P
authors.lastname: Meir
mesh_terms: D018533:Biomass; D001938:Brazil; D055864:Droughts; D018547:Plant Stems / Q000254:growth & development; D011891:Rain; D012987:Soil; D013997:Time Factors; D014197:Trees / Q000145:classification / Q000254:growth & development*; D014934:Wood / Q000254:growth & development
chemical_list: D012987:Soil