Saguaro (Carnegiea Gigantea) Densities and Reproduction Over the Northern Sonoran Desert

@article{Drezner2006SaguaroG,
  title={Saguaro (Carnegiea Gigantea) Densities and Reproduction Over the Northern Sonoran Desert},
  author={Taly Dawn Drezner},
  journal={Physical Geography},
  year={2006},
  volume={27},
  pages={505 - 518}
}
  • T. Drezner
  • Published 1 January 2006
  • Environmental Science
  • Physical Geography
Casual observations suggest that saguaro populations are densest in southeastern Arizona, although data have not been collected and no study has been done to address this topic. In addition, the topic of reproductive density has similarly never been addressed. Saguaro reproductive output is directly related to the number of adult individuals and the number of branches in the area. Thirty saguaro populations over their U.S. range were sampled to consider two variables: population density and… 
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This paper reviews the basics of a Sonoran Desert keystone cactus species, including the ecology of its establishment and high mortality, its association with nurse plants to provide ameliorated
Variability in reproductive effort of a keystone species: age and height of branch establishment
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Variations In Saguaro Cactus (Carnegiea gigantea) Spine Length In Wet and Dry Portions of Their Range
TLDR
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Variation in age and height of onset of reproduction in the saguaro cactus (Carnegiea gigantea) in the Sonoran Desert
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Statistical results are robust and significant variations in the onset of reproduction are observed by both age and height across the four sites, which have implications for regeneration, particularly in marginal locales where regeneration is already limited.
Regional Branching Relationships in Carnegiea gigantea, A Keystone Cactus
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A significant relationship in peaks and troughs is detected between the 2 very different populations, suggesting a regional influence over branching that extends beyond a population or local area.
Nonlinear modeling of saguaro growth rates reveals the importance of temperature for size-dependent growth.
TLDR
The most parsimonious model was the Ricker function that described growth considering cactus decline with age, and Variance in temperature, rather than precipitation, was more closely related to growth.
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References

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Saguaro Distribution under Nurse Plants in Arizona's Sonoran Desert: Directional and Microclimate Influences*
Abstract The saguaro cactus, an icon of the American southwestern desert, defines the extent of the Sonoran Desert through portions of its range. Saguaros rely upon nurse plants for establishment and
A test of the relationship between seasonal rainfall and saguaro cacti branching patterns
Reproductive output, as well as photosynthetically active radiation interception and CO 2 uptake, increase as saguaro cacti Carnegiea gigantea (Engelm.) Britt. and Rose branch, and branching
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  • T. Drezner
  • Environmental Science
    American journal of botany
  • 2003
TLDR
With this formula and relatively little field sampling, the age of any individual saguaro (whether the individual was sampled or not) in any population can be estimated.
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TLDR
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TLDR
If the northern limit of C gigantea reflects wintertime survival of juveniles, nurse plants could extend the range by offering some protection against freezing by extending the range of apical temperatures.
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TLDR
Olneya tesota must be considered as a habitat modifier species with ecological and conservational importance to the plant communities in the Sonoran Desert.
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Interspecific morphological differences and intraspecific morphological changes with latitude were evaluated to help examine the distributional ranges of Carnegiea gigantea, Lemaireocereus thurberi,
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