Seagrass macrofaunal abundance shows both multifractality and scale-invariant patchiness.


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Type
Article
Change log
Authors
Barnes, RSK 
Laurie, H 
Abstract

Spatial patterns of abundance of the whole macrobenthic assemblage and of its 10 most numerous species were examined across hierarchically nested scales within a 0.85 ha area of intertidal seagrass in subtropical Moreton Bay, Queensland. Multifractality characterised the assemblage and all ten dominant species across those scales (c. 33, 130, 530 & 2115 m2), with patchiness of assemblage numbers and those of at least some dominants exhibiting scale-invariance. The system displayed several abundance peaks, 12% of stations accounting for 88% of total variance, with many individual dominants showing a series of non-overlapping 'hot-spots'. Scale invariance and multifractality occurred notwithstanding low levels of species interaction consequent on maintenance at very low density. This suggests that critical self-organisation cannot be responsible for such patterning. Contrary to received wisdom, coefficient β of Taylor's power-law cannot form an index of aggregation, although it does indicate direction of change in dispersion pattern with changing numbers.

Description
Keywords
Abundance, Macrobenthos, Moreton bay, Multifractality, Patchiness, Seagrass, Self-similarity, Spatial scale, Taylor's index of aggregation, Aquatic Organisms, Ecology, Ecosystem, Environmental Monitoring, Queensland
Journal Title
Mar Environ Res
Conference Name
Journal ISSN
0141-1136
1879-0291
Volume Title
138
Publisher
Elsevier BV