Zimmermann, Julia, Higgins, Steven I., Grimm, Volker, Hoffmann, John and Linstaedter, Anja (2015). Local density effects on individual production are dynamic: insights from natural stands of a perennial savanna grass. Oecologia, 178 (4). S. 1125 - 1136. NEW YORK: SPRINGER. ISSN 1432-1939
Full text not available from this repository.Abstract
Perennial grasses are a dominant component of grasslands, and provide important ecosystem services. However, most knowledge of grasslands' functioning and production comes from plot-level studies, and drivers of individual-level production remain poorly explored. Extrapolation from existing experiments is hampered by the fact that these are mostly concentrated on even-aged cohorts, and/or on the early stages of a plant's life cycle. Here we explored how local density regulates individual production in mono-specific natural grassland, focusing on adult individuals of a perennial savanna grass (Stipagrostis uniplumis). We found individual production to increase with individuals' size, but to decrease with neighbour abundance. A metric of neighbour abundance that considered size was superior to a metric based solely on the number of individuals. This finding is particularly important for studying competitive effects in natural populations, where plants are normally not even-sized. The inferred competition kernel, i.e. the function describing how competitive strength varies with spatial distance from a target plant, was hump-shaped, indicating strongest intraspecific competition at intermediate distances (10-30 cm). The spatial signature of competitive effects changed with time since fire; peak effects moved successively away from the target plant. Our results suggest that inferred competition kernels of long-lived plant populations may have shapes that differ from exponential or sigmoidal decreases. More generally, results underline that competition among neighbouring plants is dynamic. Studies that address density-dependent and density-independent (fire-related) population dynamics of perennial grasses in their fire-prone environment may thus shed new light on the functioning and production of grasslands.
Item Type: | Journal Article | ||||||||||||||||||||||||
Creators: |
|
||||||||||||||||||||||||
URN: | urn:nbn:de:hbz:38-397854 | ||||||||||||||||||||||||
DOI: | 10.1007/s00442-015-3291-9 | ||||||||||||||||||||||||
Journal or Publication Title: | Oecologia | ||||||||||||||||||||||||
Volume: | 178 | ||||||||||||||||||||||||
Number: | 4 | ||||||||||||||||||||||||
Page Range: | S. 1125 - 1136 | ||||||||||||||||||||||||
Date: | 2015 | ||||||||||||||||||||||||
Publisher: | SPRINGER | ||||||||||||||||||||||||
Place of Publication: | NEW YORK | ||||||||||||||||||||||||
ISSN: | 1432-1939 | ||||||||||||||||||||||||
Language: | English | ||||||||||||||||||||||||
Faculty: | Unspecified | ||||||||||||||||||||||||
Divisions: | Unspecified | ||||||||||||||||||||||||
Subjects: | no entry | ||||||||||||||||||||||||
Uncontrolled Keywords: |
|
||||||||||||||||||||||||
URI: | http://kups.ub.uni-koeln.de/id/eprint/39785 |
Downloads
Downloads per month over past year
Altmetric
Export
Actions (login required)
![]() |
View Item |