Mahfuzur Rahman , Lucinda Duxbury , Haidee Cadd , Robert Klaebe , Geraldine Jacobsen , John Tibby , Jonathan Tyler
{"title":"从南澳大利亚袋鼠岛(Karti/Karta)湖泊沉积物的氧同位素推断的2000年水文气候变化记录","authors":"Mahfuzur Rahman , Lucinda Duxbury , Haidee Cadd , Robert Klaebe , Geraldine Jacobsen , John Tibby , Jonathan Tyler","doi":"10.1016/j.quascirev.2025.109443","DOIUrl":null,"url":null,"abstract":"<div><div>Understanding past hydroclimate variability through high-resolution records is key to assessing the recurrence of extreme climatic events, including prolonged droughts and floods and for sustainable environmental and economic planning. This study presents a sub-decadal-scale hydroclimate reconstruction based on oxygen isotope analysis of ostracod valves, extracted from the sediments of Lashmars Lagoon, Kangaroo Island, South Australia. Sediment dating was based on 19 accelerator mass spectrometry (AMS) radiocarbon (<sup>14</sup>C) dates from pollen and plant macrofossils, alongside lead-210 and plutonium concentration analyses. Spanning the last ∼2000 years, the oxygen isotopes record a series of multi-decadal wet and dry periods, manifest in the relative precipitation-evaporation balance of the lake. Of note, the record implies periods of prolonged declines in water balance, tentatively interpreted as droughts, from ∼525 to 575 CE, ∼770–790 CE, ∼825–850 CE, and ∼980–1020 CE. By contrast, the periods from ∼150 to 450 CE and ∼600–750 CE were relatively wet. Unfortunately, ostracods were absent within the sediments deposited between ∼1250 and 1590 CE and as a result, no hydroclimatic pattern could be determined for this time period. The period from ∼1590 to 1800 CE appears to have been notably dry, prior to an increase in effective moisture during the last 200 years. The Lashmars Lagoon record exhibits similar trends to a record from Blue Lake, Mt. Gambier, approx. 500 km to the southeast. However, these records contrast with other hydroclimate records from further east, implying a complex relationship with regional climate drivers. Comparison with instrumental period rainfall data, and reconstructed indices for major ocean–atmosphere interactions suggests that periods of increased moisture balance on Kangaroo Island were influenced by a combination of Southern Ocean and Indian Ocean derived climate drivers.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"363 ","pages":"Article 109443"},"PeriodicalIF":3.3000,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"A 2000-year record of hydroclimate variability inferred from oxygen isotopes in lake sediments on Kangaroo Island (Karti/Karta), South Australia\",\"authors\":\"Mahfuzur Rahman , Lucinda Duxbury , Haidee Cadd , Robert Klaebe , Geraldine Jacobsen , John Tibby , Jonathan Tyler\",\"doi\":\"10.1016/j.quascirev.2025.109443\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Understanding past hydroclimate variability through high-resolution records is key to assessing the recurrence of extreme climatic events, including prolonged droughts and floods and for sustainable environmental and economic planning. This study presents a sub-decadal-scale hydroclimate reconstruction based on oxygen isotope analysis of ostracod valves, extracted from the sediments of Lashmars Lagoon, Kangaroo Island, South Australia. Sediment dating was based on 19 accelerator mass spectrometry (AMS) radiocarbon (<sup>14</sup>C) dates from pollen and plant macrofossils, alongside lead-210 and plutonium concentration analyses. Spanning the last ∼2000 years, the oxygen isotopes record a series of multi-decadal wet and dry periods, manifest in the relative precipitation-evaporation balance of the lake. Of note, the record implies periods of prolonged declines in water balance, tentatively interpreted as droughts, from ∼525 to 575 CE, ∼770–790 CE, ∼825–850 CE, and ∼980–1020 CE. By contrast, the periods from ∼150 to 450 CE and ∼600–750 CE were relatively wet. Unfortunately, ostracods were absent within the sediments deposited between ∼1250 and 1590 CE and as a result, no hydroclimatic pattern could be determined for this time period. The period from ∼1590 to 1800 CE appears to have been notably dry, prior to an increase in effective moisture during the last 200 years. The Lashmars Lagoon record exhibits similar trends to a record from Blue Lake, Mt. Gambier, approx. 500 km to the southeast. However, these records contrast with other hydroclimate records from further east, implying a complex relationship with regional climate drivers. Comparison with instrumental period rainfall data, and reconstructed indices for major ocean–atmosphere interactions suggests that periods of increased moisture balance on Kangaroo Island were influenced by a combination of Southern Ocean and Indian Ocean derived climate drivers.</div></div>\",\"PeriodicalId\":20926,\"journal\":{\"name\":\"Quaternary Science Reviews\",\"volume\":\"363 \",\"pages\":\"Article 109443\"},\"PeriodicalIF\":3.3000,\"publicationDate\":\"2025-05-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Quaternary Science Reviews\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S027737912500263X\",\"RegionNum\":1,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOGRAPHY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Quaternary Science Reviews","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S027737912500263X","RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOGRAPHY, PHYSICAL","Score":null,"Total":0}
A 2000-year record of hydroclimate variability inferred from oxygen isotopes in lake sediments on Kangaroo Island (Karti/Karta), South Australia
Understanding past hydroclimate variability through high-resolution records is key to assessing the recurrence of extreme climatic events, including prolonged droughts and floods and for sustainable environmental and economic planning. This study presents a sub-decadal-scale hydroclimate reconstruction based on oxygen isotope analysis of ostracod valves, extracted from the sediments of Lashmars Lagoon, Kangaroo Island, South Australia. Sediment dating was based on 19 accelerator mass spectrometry (AMS) radiocarbon (14C) dates from pollen and plant macrofossils, alongside lead-210 and plutonium concentration analyses. Spanning the last ∼2000 years, the oxygen isotopes record a series of multi-decadal wet and dry periods, manifest in the relative precipitation-evaporation balance of the lake. Of note, the record implies periods of prolonged declines in water balance, tentatively interpreted as droughts, from ∼525 to 575 CE, ∼770–790 CE, ∼825–850 CE, and ∼980–1020 CE. By contrast, the periods from ∼150 to 450 CE and ∼600–750 CE were relatively wet. Unfortunately, ostracods were absent within the sediments deposited between ∼1250 and 1590 CE and as a result, no hydroclimatic pattern could be determined for this time period. The period from ∼1590 to 1800 CE appears to have been notably dry, prior to an increase in effective moisture during the last 200 years. The Lashmars Lagoon record exhibits similar trends to a record from Blue Lake, Mt. Gambier, approx. 500 km to the southeast. However, these records contrast with other hydroclimate records from further east, implying a complex relationship with regional climate drivers. Comparison with instrumental period rainfall data, and reconstructed indices for major ocean–atmosphere interactions suggests that periods of increased moisture balance on Kangaroo Island were influenced by a combination of Southern Ocean and Indian Ocean derived climate drivers.
期刊介绍:
Quaternary Science Reviews caters for all aspects of Quaternary science, and includes, for example, geology, geomorphology, geography, archaeology, soil science, palaeobotany, palaeontology, palaeoclimatology and the full range of applicable dating methods. The dividing line between what constitutes the review paper and one which contains new original data is not easy to establish, so QSR also publishes papers with new data especially if these perform a review function. All the Quaternary sciences are changing rapidly and subject to re-evaluation as the pace of discovery quickens; thus the diverse but comprehensive role of Quaternary Science Reviews keeps readers abreast of the wider issues relating to new developments in the field.