| Title |
Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines
|
|---|---|
| Published in |
Oecologia, August 2007
|
| DOI | 10.1007/s00442-007-0832-x |
| Pubmed ID | |
| Authors |
Nathan B. English, David L. Dettman, Darren R. Sandquist, David G. Williams |
| Abstract |
The stable isotope composition of spines produced serially from the apex of columnar cacti has the potential to be used as a record of changes in climate and physiology. To investigate this potential, we measured the delta(18)O, delta(13)C and F(14)C values of spines from a long-lived columnar cactus, saguaro (Carnegiea gigantea). To determine plant age, we collected spines at 11 different heights along one rib from the stem apex (3.77 m height) to the base of a naturally occurring saguaro. Fractions of modern carbon (F(14)C) ranged from 0.9679 to 1.5537, which is consistent with ages between 1950 and 2004. We observed a very strong positive correlation (r = 0.997) between the F(14)C age of spines and the age of spines determined from direct and repeated height measurements taken on this individual over the past 37 years. A series of 96 spines collected from this individual had delta(18)O values ranging from 38 per thousand to 50 per thousand [Vienna standard mean ocean water (VSMOW)] and delta(13)C values from -11.5 per thousand to -8.5 per thousand [Vienna Peedee belemnite (VPDB)]. The delta(18)O and delta(13)C values of spines were positively correlated (r = 0.45, P < 0.0001) and showed near-annual oscillations over the approximately 15-year record. This pattern suggests that seasonal periods of reduced evaporative demand or greater precipitation input may correspond to increased daytime CO(2) uptake. The lowest delta(18)O and delta(13)C values of spines observed occurred during the 1983 and 1993 El Niño years, suggesting that the stable isotope composition recorded in spine tissue may serve as a proxy for these climate events. We compared empirical models and data from potted experimental cacti to validate these observations and test our hypotheses. The isotopic records presented here are the first ever reported from a chronosequence of cactus spines and demonstrate that tissues of columnar cacti, and potentially other long-lived succulents, may contain a record of past physiological and climatic variation. |
X Demographics
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Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 1 | 100% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 1 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 67 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 2 | 3% |
| Argentina | 2 | 3% |
| China | 1 | 1% |
| Brazil | 1 | 1% |
| Unknown | 61 | 91% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 21 | 31% |
| Student > Ph. D. Student | 14 | 21% |
| Student > Master | 6 | 9% |
| Student > Bachelor | 4 | 6% |
| Professor | 4 | 6% |
| Other | 12 | 18% |
| Unknown | 6 | 9% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 25 | 37% |
| Environmental Science | 13 | 19% |
| Earth and Planetary Sciences | 10 | 15% |
| Social Sciences | 4 | 6% |
| Biochemistry, Genetics and Molecular Biology | 3 | 4% |
| Other | 1 | 1% |
| Unknown | 11 | 16% |
Attention Score in Context
This research output has an Altmetric Attention Score of 4. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 09 November 2023.
All research outputs
#6,949,679
of 22,789,076 outputs
Outputs from Oecologia
#1,521
of 4,210 outputs
Outputs of similar age
#23,497
of 68,766 outputs
Outputs of similar age from Oecologia
#5
of 15 outputs
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