| Title |
The effects of elevated CO2 on seed production and seedling recruitment in a sheep-grazed pasture
|
|---|---|
| Published in |
Oecologia, May 2001
|
| DOI | 10.1007/s004420000602 |
| Pubmed ID | |
| Authors |
G. Edwards, H. Clark, P. Newton |
| Abstract |
Seed production and seedling recruitment were measured over 2 years under ambient (360 ppm) and elevated (475 ppm) atmospheric CO2 in a free air carbon dioxide enrichment (FACE) experiment, carried out in a sheep-grazed pasture on dry, sandy soil in New Zealand. In both years elevated CO2 led to more dispersed seeds of the grasses Anthoxanthum odoratum, Lolium perenne and Poa pratensis, the legumes Trifolium repens and T. subterraneum and the herbs Hypochaeris radicata and Leontodon saxatilis. The increased seed dispersal in A. odoratum, H. radicata, Leontodon saxatilis and T. repens reflected both more inflorescences per unit area and more seeds per inflorescence under elevated CO2. The increased seed dispersal in Lolium perenne, P. pratensis and T. subterraneum was due solely to more inflorescences per unit area. The number of seedlings that emerged and survived to at least 7 months of age was increased by elevated CO2 for H. radicata, Leontodon saxatilis, T. repens and T. subterraneum in both years and for A. odoratum and Lolium perenne in the first year. For species where increased seedling recruitment was noted, there was a significant positive correlation between seed production in summer and seedling emergence in the following autumn and winter, and sowing 200 extra seeds per species m(-2) resulted in more seedlings compared to unsown controls. Elevated CO2 did not affect seedling survival in any species. There was no measurable effect of elevated CO2 on canopy and soil surface conditions or soil moisture at the time of seedling emergence. The results suggest the dominant effect of elevated CO2 on seedling recruitment in this pasture was an indirect one, reflecting effects on the number of seeds produced. The biomass of H. radicata, Leontodon saxatilis, T. repens and T. subterraneum in the above-ground vegetation was greater under elevated than ambient CO2. However, the size of individual seedlings and mature plants of these four species was unaffected by elevated CO2. The results indicate an important way elevated CO2 influenced plant species composition in this pasture was through changes in the pattern of seedling recruitment. |
Mendeley readers
The data shown below were compiled from readership statistics for 66 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 3 | 5% |
| France | 1 | 2% |
| Brazil | 1 | 2% |
| United Kingdom | 1 | 2% |
| Israel | 1 | 2% |
| Argentina | 1 | 2% |
| Canada | 1 | 2% |
| Unknown | 57 | 86% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 17 | 26% |
| Student > Ph. D. Student | 15 | 23% |
| Professor > Associate Professor | 6 | 9% |
| Student > Bachelor | 4 | 6% |
| Student > Master | 4 | 6% |
| Other | 10 | 15% |
| Unknown | 10 | 15% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 27 | 41% |
| Environmental Science | 14 | 21% |
| Earth and Planetary Sciences | 8 | 12% |
| Biochemistry, Genetics and Molecular Biology | 1 | 2% |
| Philosophy | 1 | 2% |
| Other | 0 | 0% |
| Unknown | 15 | 23% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. 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 01 January 2007.
All research outputs
#7,479,767
of 22,865,319 outputs
Outputs from Oecologia
#1,679
of 4,222 outputs
Outputs of similar age
#13,152
of 40,164 outputs
Outputs of similar age from Oecologia
#4
of 17 outputs
Altmetric has tracked 22,865,319 research outputs across all sources so far. This one is in the 44th percentile – i.e., 44% of other outputs scored the same or lower than it.
So far Altmetric has tracked 4,222 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 7.0. This one is in the 34th percentile – i.e., 34% of its peers scored the same or lower than it.
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We're also able to compare this research output to 17 others from the same source and published within six weeks on either side of this one. This one is in the 11th percentile – i.e., 11% of its contemporaries scored the same or lower than it.