Tesis
Relações hídricas, trocas gasosas e anatomia foliar de Vochysia divergens Pohl., espécie invasora no Pantanal mato-grossense
Fecha
2013-10-25Registro en:
DALMOLIN, Ândrea Carla. Relações hídricas, trocas gasosas e anatomia foliar de Vochysia divergens Pohl., espécie invasora no Pantanal mato-grossense. 2013. 83 f. Tese (Doutorado em Física Ambiental) - Universidade Federal de Mato Grosso, Instituto de Física, Cuiabá, 2013.
Autor
Lobo, Francisco de Almeida
Ortíz, Carmen Eugenia Rodríguez
http://lattes.cnpq.br/2783222284467182
http://lattes.cnpq.br/0296723198831816
Lobo, Francisco de Almeida
346.659.001-91
http://lattes.cnpq.br/0296723198831816
Ortíz, Carmen Eugenia Rodríguez
830.350.526-20
http://lattes.cnpq.br/2783222284467182
346.659.001-91
830.350.526-20
Vourlitis, George Louis
743.349.211-91
http://lattes.cnpq.br/5352197007462490
Dalmagro, Higo José
089.683.367-41
http://lattes.cnpq.br/2968364807067338
Gomes, Fábio Pinto
441.905.905-25
http://lattes.cnpq.br/0379787325639951
Institución
Resumen
Considered one of the major floodplains of the planet, the Pantanal of Mato Grosso is
subject to changes in rainfall that are characteristic of wetlands with periods of
flooding and drought. Characteristic rainfall function as filters for the establishment
and development of the species that co-exist there and are characteristic of the
adjacent biomes. There is growing concern regarding the establishment and
dominance of V. divergens Pohl. in the wetland by scientists as this species decreases
the biodiversity of occupied areas, modifies the chemistry of the soil and tends to
encroach on areas used for agriculture, the basis of the local economy. Ecological
studies have shown that the areas occupied by V. divergens expand in more humid
conditions and retract in drier periods. The present study investigated the hypothesis
that V. divergens reduce their metabolic rates in the dry season, which would
contribute to a decrease in their population. To determine the effects flooding and
drought on metabolic rate we evaluated water relationship (Ψω and PV curve), gas
exchange (AxCC and AxDFFA curves) and chlorophyll fluorescence parameters, as
well as leaf structure ( anatomy of photosynthetic pigment concentration and N
partitioning) of five young individuals of V. divergens in Pantanal during flood and
drought periods. The period of drought contributed to reduction of the values of Ψω,
and showed marked effects on biochemical parameters with a decrease in Vcmax and
Jmax being the most severe effects observed on the photochemistry, evidenced by
chlorophyll fluorescence parameters with a decrease in ΦPSII , and increase in F0
and ΦNPQ . However, the biochemical and photochemical damage were not severe
enough to cause changes in the gas exchange rates. These rates were maintained due
to: the increased bulk modulus of elasticity of the cell wall,. The maintenance of
positive values of potential net photosynthetic rate, despite biochemical and
photochemical limitations, and non-critical values of water potential indicate that the
species has plasticity and is adapted to the period of drought. These results suggest
that the decrease in physiological parameters of young individuals are not decisive
for the species decline.