Dataset Information

Earlywood and Latewood Stable Carbon and Oxygen Isotope Variations in Two Pine Species in Southwestern China during the Recent Decades.

ABSTRACT: Stable isotopes in wood cellulose of tree rings provide a high-resolution record of environmental conditions, yet intra-annual analysis of carbon and oxygen isotopes and their associations with physiological responses to seasonal environmental changes are still lacking. We analyzed tree-ring stable carbon (?¹³C) and oxygen (?¹⁸O) isotope variations in the earlywood (EW) and latewood (LW) of pines from a secondary forest (Pinus kesiya) and from a natural forest (Pinus armandii) in southwestern China. There was no significant difference between ?¹³C_EW and ?¹³C_LW in P. kesiya, while ?¹³C_EW was significantly higher than ?¹³C_LW in P. armandii. For both P. kesiya and P. armandii, ?¹³C_EW was highly correlated with previous year's ?¹³C_LW, indicating a strong carbon carry-over effect for both pines. The intrinsic water use efficiency (iWUE) in the earlywood of P. armandii was slightly higher than that of P. kesiya, and iWUE of both pine species showed an increasing trend, but at a considerably higher rate in P. kesiya. Respective ?¹³C_EW and ?¹³C_LW series were not correlated between the two pine species and could be influenced by local environmental factors. ?¹³C_EW of P. kesiya was positively correlated with July to September monthly mean temperature (MMT), whereas ?¹³C_EW of P. armandii was positively correlated with February to May MMT. Respective ?¹⁸O_EW and ?¹⁸O_LW in P. kesiya were positively correlated with those in P. armandii, indicating a strong common climatic forcing in ?¹⁸O for both pine species. ?¹⁸O_EW of both pine species was negatively correlated with May relative humidity and ?¹⁸O_EW in P. armandii was negatively correlated with May precipitation, whereas ?¹⁸O_LW in both pine species was negatively correlated with precipitation during autumn months, showing a high potential for climate reconstruction. Our results reveal slightly higher iWUE in natural forest pine species than in secondary forest pine species, and separating earlywood and latewood of for ?¹⁸O analyses could provide seasonally distinct climate signals in southwestern China.

SUBMITTER: Fu PL

PROVIDER: S-EPMC5223062 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Publications

Earlywood and Latewood Stable Carbon and Oxygen Isotope Variations in Two Pine Species in Southwestern China during the Recent Decades.

Fu Pei-Li PL Grießinger Jussi J Gebrekirstos Aster A Fan Ze-Xin ZX Bräuning Achim A

Frontiers in plant science 20170110

Stable isotopes in wood cellulose of tree rings provide a high-resolution record of environmental conditions, yet intra-annual analysis of carbon and oxygen isotopes and their associations with physiological responses to seasonal environmental changes are still lacking. We analyzed tree-ring stable carbon (δ13C) and oxygen (δ18O) isotope variations in the earlywood (EW) and latewood (LW) of pines from a secondary forest (Pinus kesiya) and from a natural forest (Pi ...[more]

PMID: 28119725

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Dataset Information

Earlywood and Latewood Stable Carbon and Oxygen Isotope Variations in Two Pine Species in Southwestern China during the Recent Decades.

Publications

Earlywood and Latewood Stable Carbon and Oxygen Isotope Variations in Two Pine Species in Southwestern China during the Recent Decades.

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