Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction
To develop multi-century stable isotope chronologies from tree rings, pooling techniques are applied to reduce laboratory costs and time. However, pooling of wood samples from different trees may have adverse effects on the signal amplitude in the final isotope chronology. We tested different poolin...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-06-01
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| Series: | Geosciences |
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| Online Access: | https://www.mdpi.com/2076-3263/9/6/270 |
| _version_ | 1818204303719923712 |
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| author | Zeynab Foroozan Jussi Grießinger Kambiz Pourtahmasi Achim Bräuning |
| author_facet | Zeynab Foroozan Jussi Grießinger Kambiz Pourtahmasi Achim Bräuning |
| author_sort | Zeynab Foroozan |
| collection | DOAJ |
| description | To develop multi-century stable isotope chronologies from tree rings, pooling techniques are applied to reduce laboratory costs and time. However, pooling of wood samples from different trees may have adverse effects on the signal amplitude in the final isotope chronology. We tested different pooling approaches to identify the method that is most cost-efficient, without compromising the ability of the final chronology to reflect long-term climate variability as well as climatic extreme years. As test material, we used δ<sup>18</sup>O data from juniper trees (<i>Juniperus polycarpus</i>) from Northern Iran. We compared inter-tree and shifted 5-year blocks serial pooling of stable isotope series from 5 individual trees and addition of one single series to a shifted serial pooled chronology. The inter-tree pooled chronology showed the strongest climate sensitivity and most synchronous δ<sup>18</sup>O variations with the individual tree ring analyses, while the shifted block chronologies showed a marked decline in high-frequency signals and no correlations with climate variables of the growth year. Combinations of block-pooled and single isotope series compensated the high-frequency decline but added tree-individual climatic signals. Therefore, we recommend pooling calendar synchronous tree rings from individual trees as a viable alternative to individual-tree isotope measurements for robust paleoclimate reconstructions. |
| first_indexed | 2024-12-12T03:39:06Z |
| format | Article |
| id | doaj.art-1fb0c80baeeb485eaa09628bee0da734 |
| institution | Directory Open Access Journal |
| issn | 2076-3263 |
| language | English |
| last_indexed | 2024-12-12T03:39:06Z |
| publishDate | 2019-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Geosciences |
| spelling | doaj.art-1fb0c80baeeb485eaa09628bee0da7342022-12-22T00:39:43ZengMDPI AGGeosciences2076-32632019-06-019627010.3390/geosciences9060270geosciences9060270Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate ReconstructionZeynab Foroozan0Jussi Grießinger1Kambiz Pourtahmasi2Achim Bräuning3Institute of Geography, Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, GermanyInstitute of Geography, Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, GermanyDepartment of Wood and Paper Science & Technology, Faculty of Natural Resources, University of Tehran, Karaj 31587-77871, IranInstitute of Geography, Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, GermanyTo develop multi-century stable isotope chronologies from tree rings, pooling techniques are applied to reduce laboratory costs and time. However, pooling of wood samples from different trees may have adverse effects on the signal amplitude in the final isotope chronology. We tested different pooling approaches to identify the method that is most cost-efficient, without compromising the ability of the final chronology to reflect long-term climate variability as well as climatic extreme years. As test material, we used δ<sup>18</sup>O data from juniper trees (<i>Juniperus polycarpus</i>) from Northern Iran. We compared inter-tree and shifted 5-year blocks serial pooling of stable isotope series from 5 individual trees and addition of one single series to a shifted serial pooled chronology. The inter-tree pooled chronology showed the strongest climate sensitivity and most synchronous δ<sup>18</sup>O variations with the individual tree ring analyses, while the shifted block chronologies showed a marked decline in high-frequency signals and no correlations with climate variables of the growth year. Combinations of block-pooled and single isotope series compensated the high-frequency decline but added tree-individual climatic signals. Therefore, we recommend pooling calendar synchronous tree rings from individual trees as a viable alternative to individual-tree isotope measurements for robust paleoclimate reconstructions.https://www.mdpi.com/2076-3263/9/6/270tree ringsstable oxygen isotopespooling strategiesdendroclimatologyIran |
| spellingShingle | Zeynab Foroozan Jussi Grießinger Kambiz Pourtahmasi Achim Bräuning Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction Geosciences tree rings stable oxygen isotopes pooling strategies dendroclimatology Iran |
| title | Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction |
| title_full | Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction |
| title_fullStr | Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction |
| title_full_unstemmed | Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction |
| title_short | Evaluation of Different Pooling Methods to Establish a Multi-Century δ<sup>18</sup>O Chronology for Paleoclimate Reconstruction |
| title_sort | evaluation of different pooling methods to establish a multi century δ sup 18 sup o chronology for paleoclimate reconstruction |
| topic | tree rings stable oxygen isotopes pooling strategies dendroclimatology Iran |
| url | https://www.mdpi.com/2076-3263/9/6/270 |
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