J Plant Ecol ›› 2016, Vol. 9 ›› Issue (4): 434-441 .DOI: 10.1093/jpe/rtv065

• Research Articles • Previous Articles     Next Articles

Does hydrological fluctuation alter impacts of species richness on biomass in wetland plant communities?

Fang-Li Luo#, Xing-Xing Jiang#, Hong-Li Li and Fei-Hai Yu*   

  1. School of Nature Conservation, Beijing Forestry University, Beijing 100083, China
  • Received:2015-04-22 Accepted:2015-09-23 Published:2016-07-19
  • Contact: Luo, Fang-Li

Does hydrological fluctuation alter impacts of species richness on biomass in wetland plant communities?

Abstract: Aims The diversity–productivity relationship is one of the most critical questions in ecology and can be altered by environmental factors. Hydrological fluctuation affects growth of wetland plants, and such effects vary with plant species. Therefore, we hypothesized that hydrological fluctuation changes effects of species richness on productivity of wetland plant communities.
Methods We constructed wetland plant communities consisting of three or six wetland plant species and subjected them to hydrological fluctuation (i.e. gradually changing water level) of two frequencies and two ranges, with unchanged water level as the control. We measured height, root and shoot dry mass of each plant at harvest.
Important findings Hydrological fluctuation significantly decreased biomass of wetland plant communities, which was due to impacts of fluctuation range, but not those of fluctuation frequency. Community biomass was significantly higher when species richness was higher, and such an effect did not depend on hydrological fluctuation. Therefore, hydrological fluctuation can decrease the productivity of wetland plant communities but may not alter the diversity–productivity relationship.

Key words: diversity effects, diversity-productivity relationship, experimental plant communities, flooding, fluctuation frequency, fluctuation range, water depth change

摘要:
Aims The diversity–productivity relationship is one of the most critical questions in ecology and can be altered by environmental factors. Hydrological fluctuation affects growth of wetland plants, and such effects vary with plant species. Therefore, we hypothesized that hydrological fluctuation changes effects of species richness on productivity of wetland plant communities.
Methods We constructed wetland plant communities consisting of three or six wetland plant species and subjected them to hydrological fluctuation (i.e. gradually changing water level) of two frequencies and two ranges, with unchanged water level as the control. We measured height, root and shoot dry mass of each plant at harvest.
Important findings Hydrological fluctuation significantly decreased biomass of wetland plant communities, which was due to impacts of fluctuation range, but not those of fluctuation frequency. Community biomass was significantly higher when species richness was higher, and such an effect did not depend on hydrological fluctuation. Therefore, hydrological fluctuation can decrease the productivity of wetland plant communities but may not alter the diversity–productivity relationship.