The effect of geographic range position on demographic variability in annual plants

Katharine L. Gerst, Amy L. Angert, David L Venable

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

The abundant centre model predicts that species abundance will decline from the centre towards the periphery of the geographic range. Thus, we expect to find decreases from the centre towards the edge in variables related to population dynamics such as population density and reproductive output. However, evidence for this pattern is contradictory, suggesting that geographically peripheral sites may not be ecologically peripheral. Populations may thrive in pockets of suitable habitat at the edge of the range or may be locally adapted to peripheral conditions. This study examines how the position of a site within geographic and climatic ranges of 13 species is related to the population dynamics at one common location, The Desert Laboratory at Tumamoc Hill, Tucson, AZ, USA. We used data on survival, fecundity, germination fraction and population density from a 25-year long-term data set on winter annual plants to determine whether there was a relationship between distance to the centre of the range and population dynamics. Geographic distance was calculated by determining the distance from the Desert Laboratory to the centre of the observed range determined from locality records. Climatic distance was calculated using the niche modelling software, maxent, and subtracting the mean climatic profile for the species range from that of the Desert Laboratory. There was no relationship between mean population metrics and distance metrics. We found significant relationships between some geographic distance metrics and variance in fecundity, survival and per-germinant fecundity, but not germination fraction or population density. We did not find a relationship with any metric of population dynamic variation and climatic distance. Synthesis.Our results indicate that geographic distance from the centre of the range of 13 annual plant species more strongly predicts their population dynamics than climatic distance. This study reinforces the importance of examining vital rates and their variation in order to properly capture the effect of position within a range on population dynamics.

Original languageEnglish (US)
Pages (from-to)591-599
Number of pages9
JournalJournal of Ecology
Volume99
Issue number2
DOIs
StatePublished - Mar 2011

Fingerprint

annual plant
population dynamics
demographic statistics
fecundity
deserts
population density
desert
germination
effect
niche
reproductive performance
niches
software
synthesis
winter
habitat
habitats
modeling
laboratory

Keywords

  • Abundant centre model
  • Annual plants
  • Demographic variability
  • Geographic range
  • Niche modelling
  • Plant population and community dynamics
  • Sonoran Desert

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Plant Science

Cite this

The effect of geographic range position on demographic variability in annual plants. / Gerst, Katharine L.; Angert, Amy L.; Venable, David L.

In: Journal of Ecology, Vol. 99, No. 2, 03.2011, p. 591-599.

Research output: Contribution to journalArticle

Gerst, Katharine L. ; Angert, Amy L. ; Venable, David L. / The effect of geographic range position on demographic variability in annual plants. In: Journal of Ecology. 2011 ; Vol. 99, No. 2. pp. 591-599.
@article{288d13aa6bab40b498c7d3240ab5c11f,
title = "The effect of geographic range position on demographic variability in annual plants",
abstract = "The abundant centre model predicts that species abundance will decline from the centre towards the periphery of the geographic range. Thus, we expect to find decreases from the centre towards the edge in variables related to population dynamics such as population density and reproductive output. However, evidence for this pattern is contradictory, suggesting that geographically peripheral sites may not be ecologically peripheral. Populations may thrive in pockets of suitable habitat at the edge of the range or may be locally adapted to peripheral conditions. This study examines how the position of a site within geographic and climatic ranges of 13 species is related to the population dynamics at one common location, The Desert Laboratory at Tumamoc Hill, Tucson, AZ, USA. We used data on survival, fecundity, germination fraction and population density from a 25-year long-term data set on winter annual plants to determine whether there was a relationship between distance to the centre of the range and population dynamics. Geographic distance was calculated by determining the distance from the Desert Laboratory to the centre of the observed range determined from locality records. Climatic distance was calculated using the niche modelling software, maxent, and subtracting the mean climatic profile for the species range from that of the Desert Laboratory. There was no relationship between mean population metrics and distance metrics. We found significant relationships between some geographic distance metrics and variance in fecundity, survival and per-germinant fecundity, but not germination fraction or population density. We did not find a relationship with any metric of population dynamic variation and climatic distance. Synthesis.Our results indicate that geographic distance from the centre of the range of 13 annual plant species more strongly predicts their population dynamics than climatic distance. This study reinforces the importance of examining vital rates and their variation in order to properly capture the effect of position within a range on population dynamics.",
keywords = "Abundant centre model, Annual plants, Demographic variability, Geographic range, Niche modelling, Plant population and community dynamics, Sonoran Desert",
author = "Gerst, {Katharine L.} and Angert, {Amy L.} and Venable, {David L}",
year = "2011",
month = "3",
doi = "10.1111/j.1365-2745.2010.01782.x",
language = "English (US)",
volume = "99",
pages = "591--599",
journal = "Journal of Ecology",
issn = "0022-0477",
publisher = "Wiley-Blackwell",
number = "2",

}

TY - JOUR

T1 - The effect of geographic range position on demographic variability in annual plants

AU - Gerst, Katharine L.

AU - Angert, Amy L.

AU - Venable, David L

PY - 2011/3

Y1 - 2011/3

N2 - The abundant centre model predicts that species abundance will decline from the centre towards the periphery of the geographic range. Thus, we expect to find decreases from the centre towards the edge in variables related to population dynamics such as population density and reproductive output. However, evidence for this pattern is contradictory, suggesting that geographically peripheral sites may not be ecologically peripheral. Populations may thrive in pockets of suitable habitat at the edge of the range or may be locally adapted to peripheral conditions. This study examines how the position of a site within geographic and climatic ranges of 13 species is related to the population dynamics at one common location, The Desert Laboratory at Tumamoc Hill, Tucson, AZ, USA. We used data on survival, fecundity, germination fraction and population density from a 25-year long-term data set on winter annual plants to determine whether there was a relationship between distance to the centre of the range and population dynamics. Geographic distance was calculated by determining the distance from the Desert Laboratory to the centre of the observed range determined from locality records. Climatic distance was calculated using the niche modelling software, maxent, and subtracting the mean climatic profile for the species range from that of the Desert Laboratory. There was no relationship between mean population metrics and distance metrics. We found significant relationships between some geographic distance metrics and variance in fecundity, survival and per-germinant fecundity, but not germination fraction or population density. We did not find a relationship with any metric of population dynamic variation and climatic distance. Synthesis.Our results indicate that geographic distance from the centre of the range of 13 annual plant species more strongly predicts their population dynamics than climatic distance. This study reinforces the importance of examining vital rates and their variation in order to properly capture the effect of position within a range on population dynamics.

AB - The abundant centre model predicts that species abundance will decline from the centre towards the periphery of the geographic range. Thus, we expect to find decreases from the centre towards the edge in variables related to population dynamics such as population density and reproductive output. However, evidence for this pattern is contradictory, suggesting that geographically peripheral sites may not be ecologically peripheral. Populations may thrive in pockets of suitable habitat at the edge of the range or may be locally adapted to peripheral conditions. This study examines how the position of a site within geographic and climatic ranges of 13 species is related to the population dynamics at one common location, The Desert Laboratory at Tumamoc Hill, Tucson, AZ, USA. We used data on survival, fecundity, germination fraction and population density from a 25-year long-term data set on winter annual plants to determine whether there was a relationship between distance to the centre of the range and population dynamics. Geographic distance was calculated by determining the distance from the Desert Laboratory to the centre of the observed range determined from locality records. Climatic distance was calculated using the niche modelling software, maxent, and subtracting the mean climatic profile for the species range from that of the Desert Laboratory. There was no relationship between mean population metrics and distance metrics. We found significant relationships between some geographic distance metrics and variance in fecundity, survival and per-germinant fecundity, but not germination fraction or population density. We did not find a relationship with any metric of population dynamic variation and climatic distance. Synthesis.Our results indicate that geographic distance from the centre of the range of 13 annual plant species more strongly predicts their population dynamics than climatic distance. This study reinforces the importance of examining vital rates and their variation in order to properly capture the effect of position within a range on population dynamics.

KW - Abundant centre model

KW - Annual plants

KW - Demographic variability

KW - Geographic range

KW - Niche modelling

KW - Plant population and community dynamics

KW - Sonoran Desert

UR - http://www.scopus.com/inward/record.url?scp=79951561373&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79951561373&partnerID=8YFLogxK

U2 - 10.1111/j.1365-2745.2010.01782.x

DO - 10.1111/j.1365-2745.2010.01782.x

M3 - Article

AN - SCOPUS:79951561373

VL - 99

SP - 591

EP - 599

JO - Journal of Ecology

JF - Journal of Ecology

SN - 0022-0477

IS - 2

ER -