Inter-specific competition: Spartina alterniflora is replacing Spartina anglica in coastal China

• Published in: Estuarine, coastal and shelf science Vol. 74; no. 3; pp. 437 - 448
• Main Authors: Zhi, Yingbiao, Li, Hongli, An, Shuqing, Zhao, Lei, Zhou, Changfang, Deng, Zifa
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 01-09-2007; Elsevier
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Brackish water ecosystems; competitive intensity; Fundamental and applied biological sciences. Psychology; inter-specific competition; Marine; Relative Neighbour Effect (RNE); Spartina alterniflora; Spartina anglica; Synecology; Asia; China; INW, China, People's Rep; Spartina anglica; competitive intensity; Spartina alterniflora; Relative Neighbour Effect (RNE); inter-specific competition; Brackish water environment; Monocotyledones; Gramineae; Angiospermae; Interspecific competition; Spermatophyta
• ISSN: 0272-7714; 1096-0015
• DOI: 10.1016/j.ecss.2007.04.026

Spartina anglica C. E Hubbard, an invasive species world wide, underwent rapid invasion before the 1990s and followed by a drastic decline in costal China since its first introduction from Europe in 1963. It was hypothesized that the competition with
Spartina alterniflora Loisel., introduced into China in 1979, might play an important role in this decline due to their overlapping niche existed in the field. In this paper, we evaluated relative competitive ability using the Relative Neighbour Effect (RNE) index and the growth responses of the two species under both independent and mixed planting experiments. Several performance indices, including culm height, as well as above-ground, below-ground and spike biomass, were significantly higher in
S. alterniflora than
S. anglica. The relative inter-specific competitive ability of
S. alterniflora was significantly greater than that of
S. anglica and
S. alterniflora exerted an asymmetric, competitive dominance over
S. anglica. The competition remarkably reduced several performance parameters in
S. anglica including: above-ground biomass, culm height, stalk diameter, number of leaves, number of roots, max root length, leaf area, leaf thickness; numbers of ramets, rhizomes, internodes of total rhizomes, vegetative tillers (and consequently total tillers), and total length of rhizomes. This substantial growth advantage of
S. alterniflora might explain its greater inter-specific competitive ability, and suggests a mechanism by which
S. alterniflora has been able to replace
S. anglica and quickly invade the natural salt marsh communities of coastal China.