Dataset Information

Increased water use efficiency does not prevent growth decline of Pinus canariensis in a semi-arid treeline ecotone in Tenerife, Canary Islands (Spain).

ABSTRACT: KEY MESSAGE:Intrinsic water-use efficiency of Pinus canariensis (Sweet ex Spreng.) growing at a semi-arid treeline has increased during the past 37 years. Tree-ring width by contrast has declined, likely caused by reduced stomatal conductance due to increasing aridity. CONTEXT:Rising atmospheric CO2 concentration (Ca ) has been related to tree growth enhancement accompanied by increasing intrinsic water-use-efficiency (iWUE). Nevertheless, the extent of rising Ca on long-term changes in iWUE and growth has remained poorly understood to date in Mediterranean treeline ecosystems. AIMS:This study aimed to examine radial growth and physiological responses of P. canariensis in relation to rising Ca and increasing aridity at treeline in Tenerife, Canary Islands, Spain. METHODS:We evaluated temporal changes in secondary growth (tree-ring width; TRW) and tree ring stable C isotope signature for assessing iWUE from 1975 through 2011. RESULTS:Precipitation was the main factor controlling secondary growth. Over the last 36 years P. canariensis showed a decline in TRW at enhanced iWUE, likely caused by reduced stomatal conductance due to increasing aridity. CONCLUSION:Our results indicate that increasing aridity has overridden the potential CO2 fertilization on tree growth of P. canariensis at its upper distribution limit.

SUBMITTER: Brito P

PROVIDER: S-EPMC4961253 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Increased water use efficiency does not prevent growth decline of <i>Pinus canariensis</i> in a semi-arid treeline ecotone in Tenerife, Canary Islands (Spain).

Brito Patricia P Grams Thorsten E E TE Matysssek Rainer R Jimenez Maria S MS Gonzalez-Rodríguez Agueda M AM Oberhuber Walter W Wieser Gerhard G

Annals of forest science 20160607 3

<h4>Key message</h4>Intrinsic water-use efficiency of <i>Pinus canariensis</i> (Sweet <i>ex</i> Spreng.) growing at a semi-arid treeline has increased during the past 37 years. Tree-ring width by contrast has declined, likely caused by reduced stomatal conductance due to increasing aridity.<h4>Context</h4>Rising atmospheric CO<sub>2</sub> concentration (<i>C<sub>a</sub></i> ) has been related to tree growth enhancement accompanied by increasing intrinsic water-use-efficiency (iWUE). Nevertheless ...[more]

PMID: 27482149

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Dataset Information

Increased water use efficiency does not prevent growth decline of Pinus canariensis in a semi-arid treeline ecotone in Tenerife, Canary Islands (Spain).

Publications

Increased water use efficiency does not prevent growth decline of <i>Pinus canariensis</i> in a semi-arid treeline ecotone in Tenerife, Canary Islands (Spain).

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