کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6427225 1634701 2016 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Abrupt plant physiological changes in southern New Zealand at the termination of the Mi-1 event reflect shifts in hydroclimate and pCO2
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
پیش نمایش صفحه اول مقاله
Abrupt plant physiological changes in southern New Zealand at the termination of the Mi-1 event reflect shifts in hydroclimate and pCO2
چکیده انگلیسی


- Changes in leaf physiology, δ13C and δD are recorded from a ∼100 kyr terrestrial sequence at the O/M boundary in southern New Zealand.
- Record indicates an abrupt ecosystem physiological change at the Mi-1 termination.
- Indicative of a sharp increase in atmospheric pCO2 as well as local precipitation.
- CO2 increase contemporaneous to the onset of the Antarctic Ice Sheet deterioration.

A rise in atmospheric CO2 is believed to be necessary for the termination of large-scale glaciations. Although the Antarctic Ice Sheet is estimated to have melted from ∼125% to ∼50% its modern size, there is thus far no evidence for an increase in atmospheric CO2 associated with the Mi-1 glacial termination in the earliest Miocene. Here, we present evidence from a high-resolution terrestrial record of leaf physiological change in southern New Zealand for an abrupt increase in atmospheric CO2 coincident with the termination of the Mi-1 glaciation and lasting approximately 20 kyr. Quantitative pCO2 estimates, made using a leaf gas exchange model, suggest that atmospheric CO2 levels may have doubled during this period, from 516±111ppm to 1144±410ppm, and subsequently returned back to 425±53ppm. The 20-kyr interval with high pCO2 estimates is also associated with a period of increased moisture supply to southern New Zealand, inferred from carbon and hydrogen isotopes of terrestrial leaf waxes. The results provide the first high-resolution record of terrestrial environmental change at the Oligocene/Miocene boundary, document a ∼20 kyr interval of elevated pCO2 and increased local moisture availability, and provide insight into ecosystem response to a major orbitally driven climatic transition.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth and Planetary Science Letters - Volume 455, 1 December 2016, Pages 115-124
نویسندگان
, , ,