The invasibility of marine algal assemblages: role of functional diversity and identity.
نویسندگان
چکیده
The emergence of the biodiversity-ecosystem functioning debate in the last decade has renewed interest in understanding why some communities are more easily invaded than others and how the impact of invasion on recipient communities and ecosystems varies. To date most of the research on invasibility has focused on taxonomic diversity, i.e., species richness. However, functional diversity of the communities should be more relevant for the resistance of the community to invasions, as the extent of functional differences among the species in an assemblage is a major determinant of ecosystem processes. Although coastal marine habitats are among the most heavily invaded ecosystems, studies on community invasibility and vulnerability in these habitats are scarce. We carried out a manipulative field experiment in tide pools of the rocky intertidal to test the hypothesis that increasing functional richness reduces the susceptibility of macroalgal communities to invasion. We selected a priori four functional groups on the basis of previous knowledge of local species characteristics: encrusting, turf, subcanopy, and canopy species. Synthetic assemblages containing one, two, three, or four different functional groups of seaweeds were created, and invasion by native species was monitored over an eight-month period. Cover and resource availability in the assemblages with only one functional group showed different patterns in the use of space and light, confirming true functional differences among our groups. Experimental results showed that the identity of functional groups was more important than functional richness in determining the ability of macroalgal communities to resist invasion and that resistance to invasion was resource-mediated.
منابع مشابه
Genetic diversity of 'satellite' bacteria present in cultures of marine diatoms.
Abstract Uni-algal, non-axenic cultures of six marine diatoms were screened by polymerase chain reaction-denaturing gradient gel electrophoresis for the diversity of the accompanying bacterial communities ('satellite' bacteria) in order to test the hypothesis that algal cells constitute niches for specific bacterial species. The complexity of the satellite assemblages, as judged from the number...
متن کاملDiversity, growth forms and rhodolith distribution: factors controlling the fabric of coralline algae of the early Miocene deposits, Cairo – Suez road, Egypt
The Lower Miocene deposits in Gabal Gharra, Cairo – Suez District, unconformably overlies the Oligocene and Eocene deposits. They consist predominantly of regressive and transgressive mixed siliciclastic / carbonate sediments of shallow marine environments. The Lower Miocene deposits are represented lithostratigraphically by the Gharra Formation that comprises four members, from base to top: Ag...
متن کاملOrigin matters: diversity affects the performance of alien invasive species but not of native species.
At local scales, it has often been found that invasibility decreases with increasing resident plant diversity. However, whether resident community diversity similarly resists invasion by alien versus native species is seldom studied. We examined this issue by invading constructed native plant assemblages that varied in species and functional richness with invasive alien or native Asteraceae spe...
متن کاملDistribution, Diversity and Abundance of Benthic Foraminifera of the Northwstern Persian Gulf
During ROPME Winter Cruise 2006, twenty six surface sediment samples taken from the Northwestern part of the Persian Gulf at depths of 13-77m were analyzed for their foraminifera content. A total of 93 species of benthic foraminifera were found in the study area. The foraminifera assemblages were dominated by Ammonia beccarii, Spiroloculina excavata, S. depressa, Quinqueloculina dimidiata,...
متن کاملFish diversity and assemblages according to distance from source along a coastal river gradient (Ehania River south-east of Ivory Coast)
Fish assemblage was investigated during the study of longitudinal profile of the Ehania River Basin in south-eastern Côte d’Ivoire. This area is subjected to intense human activities with many plantations (palm tree, banana, pineapple, coffee, rubber and cocoa). Samples were collected, with gillnets of different mesh sizes, through 6 sampling surveys during dry and rainy seasons from February 2...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Ecology
دوره 87 11 شماره
صفحات -
تاریخ انتشار 2006