Short-term effects of elevated CO2 on periphyton community in an artificially constructed channel

Hye-Jin Park,Baik-Ho Kim,Dae-Ryul Kwon,Soon-Jin Hwang

doi:10.1186/s41610-016-0009-9

Abstract

Direct impact of inorganic carbon (i.e., carbon dioxide (CO2)) on the periphyton community is important to understand how and to what extent atmospheric conditions can affect the structure and dynamics of these communities in lotic systems. We investigated the influence of elevated CO2 concentration on the periphyton community in the artificially constructed channels during the winter period. The channels made of acrylic paneling were continuously supplied with surface water discharged from a small reservoir, which was supported with ground water, at a flow rate of 5 L/min, and water temperature ranging 4–5 °C. The effects of elevated CO2 concentrations (790 ppm) were evaluated in comparison with the control (395 ppm CO2) by analyzing pH, water carbon content and nutrients in water, periphyton composition and biomass, chlorophyll-a, ash-free dry-matter at 2-day intervals for 10 days. After the addition of CO2, significant decreases of pH, NH3-N, and PO4-P (p < 0.05) and increases of chlorophyll-a, ash-free dry-matter, and the cell density of periphyton (p < 0.01) were observed, whereas the species composition of periphyton and water carbon content did not change. These results suggest that elevated CO2 in flowing water system with low temperature could facilitate the growth of periphyton resulting in biomass increase, which could further influence water quality and the consumers throughout the food web.

Highlights

Direct impact of inorganic carbon (i.e., carbon dioxide (CO2)) on the periphyton community is important to understand how and to what extent atmospheric conditions can affect the structure and dynamics of these communities in lotic systems
The pH of the water was similar between the groups before injecting CO2 but decreased significantly in the treatment group compared with the control group over the course of the experiment (p = 0.026; Table 1 and Fig. 2)
The majority of nutrients (i.e., NO2-N, NO3-N, NH3-N, total nitrogen (TN), PO4-P, and total phosphorous (TP)) showed a slight decrease in the treatment group compared to the control group, but the difference was not significant (Fig. 3 and Table 1)

Summary

Introduction

Direct impact of inorganic carbon (i.e., carbon dioxide (CO2)) on the periphyton community is important to understand how and to what extent atmospheric conditions can affect the structure and dynamics of these communities in lotic systems. We investigated the influence of elevated CO2 concentration on the periphyton community in the artificially constructed channels during the winter period. Carbon dioxide (CO2) is a major greenhouse gas with the greatest potential to influence global climate change since the industrial revolution, while the CO2 emission into the atmosphere has been increasing, and its concentration will reportedly double in the 50–100 years (Houghton et al 2001). The atmospheric CO2 concentration during the winter season typically increases due to the reduction of photosynthesis of plants and an increase in active consumption of fossil fuels (Lewis and Nocera 2006; Sayre 2010). Low water temperature during the winter increases CO2 solubility (Tortell et al 2008), which may be expected to affect aquatic ecosystems.

Methods

Results

Conclusion