Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem

Source water used by woody perennials in a Brazilian savanna (Cerrado) was determined by comparing the stable hydrogen isotope composition (δD) of xylem sap and soil water at different depths during two consecutive dry seasons (1995 and 1996). Plant water status and rates of water use were also dete...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Goldstein, Guillermo Hernan, Igler, Erica, Causin, Humberto Fabio
Publicado: 1999
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0829318X_v19_n11_p717_Jackson
http://hdl.handle.net/20.500.12110/paper_0829318X_v19_n11_p717_Jackson
Aporte de:
id paper:paper_0829318X_v19_n11_p717_Jackson
record_format dspace
spelling paper:paper_0829318X_v19_n11_p717_Jackson2023-06-08T15:46:04Z Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem Goldstein, Guillermo Hernan Igler, Erica Causin, Humberto Fabio Deciduous Deuterium Evergreen Hydraulic lift Neotropical savanna Resource partitioning Roots Stable hydrogen isotope composition cerrado niche partitioning soil water tree water use Brazil Source water used by woody perennials in a Brazilian savanna (Cerrado) was determined by comparing the stable hydrogen isotope composition (δD) of xylem sap and soil water at different depths during two consecutive dry seasons (1995 and 1996). Plant water status and rates of water use were also determined and compared with xylem water δD values. Overall, soil water δD decreased with increasing depth in the soil profile. Mean δD values were -35‰ for the upper 170 cm of soil and -55‰ between 230 and 400 cm depth at the end of the 1995 dry season. Soil water content increased with depth, from 18% near the surface to about 28% at 400 cm. A similar pattern of decreasing soil water δD with increasing depth was observed at the end of the 1996 dry season. Patterns consistent with hydraulic lift were observed in soil profiles sampled in 1995 and 1997. Concurrent analyses of xylem and soil water δD values indicated a distinct partitioning of water resources among 10 representative woody species (five deciduous and five evergreen). Among these species, four evergreen and one deciduous species acquired water primarily in the upper soil layers (above 200 cm), whereas three deciduous and one evergreen species tapped deep sources of soil water (below 200 cm). One deciduous species exhibited intermediate behavior. Total daily sap flow was negatively correlated with xylem sap δD values indicating that species with higher rates of water use during the dry season tended to rely on deeper soil water sources. Among evergreen species, minimum leaf water potentials were also negatively correlated with xylem water δD values, suggesting that access to more readily available water at greater depth permitted maintenance of a more favorable plant water status. No significant relationship between xylem water δD and plant size was observed in two evergreen species, suggesting a strong selective pressure for small plants to rapidly develop a deep root system. The degree of variation in soil water partitioning, leaf phenology and leaf longevity was consistent with the high diversity of woody species in the Cerrado. Fil:Goldstein, G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Igler, E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Causin, F. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 1999 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0829318X_v19_n11_p717_Jackson http://hdl.handle.net/20.500.12110/paper_0829318X_v19_n11_p717_Jackson
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Deciduous
Deuterium
Evergreen
Hydraulic lift
Neotropical savanna
Resource partitioning
Roots
Stable hydrogen isotope composition
cerrado
niche partitioning
soil water
tree
water use
Brazil
spellingShingle Deciduous
Deuterium
Evergreen
Hydraulic lift
Neotropical savanna
Resource partitioning
Roots
Stable hydrogen isotope composition
cerrado
niche partitioning
soil water
tree
water use
Brazil
Goldstein, Guillermo Hernan
Igler, Erica
Causin, Humberto Fabio
Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem
topic_facet Deciduous
Deuterium
Evergreen
Hydraulic lift
Neotropical savanna
Resource partitioning
Roots
Stable hydrogen isotope composition
cerrado
niche partitioning
soil water
tree
water use
Brazil
description Source water used by woody perennials in a Brazilian savanna (Cerrado) was determined by comparing the stable hydrogen isotope composition (δD) of xylem sap and soil water at different depths during two consecutive dry seasons (1995 and 1996). Plant water status and rates of water use were also determined and compared with xylem water δD values. Overall, soil water δD decreased with increasing depth in the soil profile. Mean δD values were -35‰ for the upper 170 cm of soil and -55‰ between 230 and 400 cm depth at the end of the 1995 dry season. Soil water content increased with depth, from 18% near the surface to about 28% at 400 cm. A similar pattern of decreasing soil water δD with increasing depth was observed at the end of the 1996 dry season. Patterns consistent with hydraulic lift were observed in soil profiles sampled in 1995 and 1997. Concurrent analyses of xylem and soil water δD values indicated a distinct partitioning of water resources among 10 representative woody species (five deciduous and five evergreen). Among these species, four evergreen and one deciduous species acquired water primarily in the upper soil layers (above 200 cm), whereas three deciduous and one evergreen species tapped deep sources of soil water (below 200 cm). One deciduous species exhibited intermediate behavior. Total daily sap flow was negatively correlated with xylem sap δD values indicating that species with higher rates of water use during the dry season tended to rely on deeper soil water sources. Among evergreen species, minimum leaf water potentials were also negatively correlated with xylem water δD values, suggesting that access to more readily available water at greater depth permitted maintenance of a more favorable plant water status. No significant relationship between xylem water δD and plant size was observed in two evergreen species, suggesting a strong selective pressure for small plants to rapidly develop a deep root system. The degree of variation in soil water partitioning, leaf phenology and leaf longevity was consistent with the high diversity of woody species in the Cerrado.
author Goldstein, Guillermo Hernan
Igler, Erica
Causin, Humberto Fabio
author_facet Goldstein, Guillermo Hernan
Igler, Erica
Causin, Humberto Fabio
author_sort Goldstein, Guillermo Hernan
title Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem
title_short Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem
title_full Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem
title_fullStr Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem
title_full_unstemmed Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem
title_sort partitioning of soil water among tree species in a brazilian cerrado ecosystem
publishDate 1999
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0829318X_v19_n11_p717_Jackson
http://hdl.handle.net/20.500.12110/paper_0829318X_v19_n11_p717_Jackson
work_keys_str_mv AT goldsteinguillermohernan partitioningofsoilwateramongtreespeciesinabraziliancerradoecosystem
AT iglererica partitioningofsoilwateramongtreespeciesinabraziliancerradoecosystem
AT causinhumbertofabio partitioningofsoilwateramongtreespeciesinabraziliancerradoecosystem
_version_ 1768541617055072256