Effects of N and P enrichment on competition between phytoplankton and benthic algae in shallow lakes: a mesocosm study: Environmental Science and Pollution Research

TY - JOUR

T1 - Effects of N and P enrichment on competition between phytoplankton and benthic algae in shallow lakes: a mesocosm study

T2 - Environmental Science and Pollution Research

AU - Zhang, Xiufeng

AU - Mei, Xueying

AU - Gulati, Ramesh

AU - Liu, Zhengwen

N1 - 5727, AqE; Data archiving: data archived at Department of Ecology and Institute of Hydrobiology, Jinan University

PY - 2015

Y1 - 2015

N2 - Competition for resources between coexisting phytoplankton and benthic algae, but with different habitats and roles in functioning of lake ecosystems, profoundly affects dynamics of shallow lakes in the process of eutrophication. An experiment was conducted to test the hypothesis that combined enrichment with nitrogen (N) and phosphorus (P) would be a greater benefit to phytoplankton than benthic algae. The growth of phytoplankton and benthic algae was measured as chlorophyll a (Chl a) in 12 shallow aquatic mesocosms supplemented with N, P, or both. We found that enrichment with N enhanced growth of benthic algae, but not phytoplankton. P enrichment had a negative effect on benthic algal growth, and no effect on the growth of phytoplankton. N+P enrichment had a negative effect on benthic algae, but enhanced the growth of phytoplankton, thus reducing the proportion of benthic algae contributing to the combined biomass of these two groups of primary producers. Thus, combined N+P enrichment is more favorable to phytoplankton in competition with benthic algae than enrichment with either N or P alone. Our study indicates that combined enrichment with N+P promotes the dominance of phytoplankton over benthic algae, with consequences for the trophic dynamics of shallow lake ecosystems.

AB - Competition for resources between coexisting phytoplankton and benthic algae, but with different habitats and roles in functioning of lake ecosystems, profoundly affects dynamics of shallow lakes in the process of eutrophication. An experiment was conducted to test the hypothesis that combined enrichment with nitrogen (N) and phosphorus (P) would be a greater benefit to phytoplankton than benthic algae. The growth of phytoplankton and benthic algae was measured as chlorophyll a (Chl a) in 12 shallow aquatic mesocosms supplemented with N, P, or both. We found that enrichment with N enhanced growth of benthic algae, but not phytoplankton. P enrichment had a negative effect on benthic algal growth, and no effect on the growth of phytoplankton. N+P enrichment had a negative effect on benthic algae, but enhanced the growth of phytoplankton, thus reducing the proportion of benthic algae contributing to the combined biomass of these two groups of primary producers. Thus, combined N+P enrichment is more favorable to phytoplankton in competition with benthic algae than enrichment with either N or P alone. Our study indicates that combined enrichment with N+P promotes the dominance of phytoplankton over benthic algae, with consequences for the trophic dynamics of shallow lake ecosystems.

KW - Benthic algae

KW - Phytoplankton

KW - Nutrient

KW - Resource competition

KW - Shallow lakes

KW - Eutrophication

KW - international

U2 - 10.1007/s11356-014-3680-3

DO - 10.1007/s11356-014-3680-3

M3 - Article

SN - 0944-1344

VL - 22

SP - 4418

EP - 4424

JO - Environmental Science and Pollution Research

JF - Environmental Science and Pollution Research

IS - 6

ER -