Till startsida
Webbkarta
Till innehåll Läs mer om hur kakor används på gu.se

How to tell a shrub from a tree: A life-history perspective from a South African savanna

Artikel i vetenskaplig tidskrift
Författare Alexander Zizka
N Govender
Steve Higgins
Publicerad i Austral Ecology
Volym 39
Nummer/häfte 7
Sidor 767-778
ISSN 1442-9985
Publiceringsår 2014
Publicerad vid Institutionen för biologi och miljövetenskap
Sidor 767-778
Språk en
Länkar http://dx.doi.org/10.1111/aec.1214...
Ämneskategorier Ekologi

Sammanfattning

The ecological differences between shrubs' and trees' are surprisingly poorly understood and clear ecological definitions of these two constructs do not exist. It is not clear whether a shrub is simply a small tree or whether shrubs represent a distinct life-history strategy. This question is of special interest in African savannas, where shrubs and trees often co-dominate, but are often treated uniformly as woody plants' even though the tree to shrub ratio is an important determinant of ecosystem functioning. In this study we use data from a long-term fire experiment, together with a trait-based approach to test (i) if woody species usually classified as shrubs or trees in African savanna differ in key traits related to disturbance and resource use; and (ii) if these differences justify the interpretation of the two growth forms as distinct life-history strategies. We measured for 22 of the most common woody plant species of a South African savanna 27 plant traits related to plant architecture, life-history, leaf characteristics, photosynthesis and resprouting capacity. Furthermore we evaluated their performance during a long-term fire experiment. We found that woody plants authors call (i) shrubs; (ii) shrubs sometimes small trees; and (3) trees responded differently to long-term fire treatments. We additionally found significant differences in architecture, diameter-height-allometry, foliage density, resprouting vigour after fire, minimum fruiting height and foliar C-13 between these three woody plant types. We interpret these findings as evidence for at least two different life-history-strategies: an avoidance/adaptation strategy for shrubs (early reproduction+adaptation to minor disturbance) and an escape strategy for trees (promoted investment in height growth+delayed reproduction).

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11
Dela:

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?