An approach to determination of functional species pool for community research

To develop a feasible protocol for determining a functional species pool for ecological research on community pattern, a multivariate approach (step-best-matching analysis) was used to select the influential species from the 40 raw data points of microperiphyton. Samples were collected monthly at a depth of 1 m from four sampling stations within a gradient of environmental stress from August 2011 to July 2012 in coastal waters of the Yellow Sea, northern China. From the full 141-species set of microperiphyton fauna, a 76-species subset with sufficient information of the whole community was identified. The subset maintained sufficient information of entire raw communities (correlation coefficient >0.95), and was more strongly related to changes of environmental variables than full set. The species number, individual abundance and biodiversity indices based on this subset were significantly correlated with those of the full species set. These results demonstrated that the subset might be used as a functional species pool for community-based bioassessment, and thus, we suggest that the step-best-matching method may be a robust time-efficient protocol to determine the functional species, and allows improvement of sampling strategies for community-based ecological research and monitoring programs on large temporal and spatial scale.