Effects of Water Quality Adjusted by Submerged Macrophytes on the Richness of the Epiphytic Algal Community

Tian Lv,Dan Yu,Yaping Hong,Chunhua Liu,Qiankun He

doi:10.3389/fpls.2018.01980

Abstract

Submerged macrophytes and epiphytic algae play significant roles in the functioning of aquatic ecosystems. Submerged macrophytes can influence the epiphytic algal community by directly or indirectly modifying environmental conditions (nutrients, light, etc.). From December to June of the following year, we investigated the dynamics of the dominant winter species Potamogeton crispus, its epiphytic algae, and water quality parameters in the shallow Liangzi Lake in China. The richness of epiphytic algae had a trend similar to that of P. crispus coverage, which increased in the first four months and then decreased in the following three months. The structural equation model (SEM) showed that P. crispus affected the richness of epiphytic algae by reducing nutrient concentrations (reduction in total organic carbon, total nitrogen and chemical oxygen demand) and enhancing water transparency (reduction in turbidity and total suspend solids) to enhance the richness of epiphytic algae. The results indicated that high amounts of submerged macrophyte cover can increase the richness of the epiphytic algal community by changing water quality.

Highlights

A least-disturbed shallow ecosystem should have high water quality and biodiversity (Mcnaughton, 1988; Downing et al, 2014)
The six values (i.e., Turb, SS, Total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), and chemical oxygen demand (COD)) in April were smaller than those in other months, which indicated that the water column was cleaner in April than in other months
The mean macrophyte cover increased from 28% in December to 38% in January of following the year, showing that P. crispus slowly grew throughout the winter

Summary

Introduction

A least-disturbed shallow ecosystem should have high water quality and biodiversity (Mcnaughton, 1988; Downing et al, 2014). Submerged macrophytes play a significant role in maintaining good water quality and high biodiversity in shallow ecosystems (Jeppesen et al, 1998; Kuiper et al, 2017). Epiphytic algae play a significant role in the functioning of shallow ecosystems, contributing to material circulation, energy flow and the maintenance of food webs (Rodusky et al, 2001; Vadeboncoeur and Steinman, 2002; Song et al, 2017). It is widely acknowledged that the relationship between epiphytic algae and macrophytes plays an important role in maintaining the function and stability of the shallow ecosystems (Liboriussen and Jeppesen, 2006; Scheffer and Nes, 2007). It is reasonable to assume that macrophytes may be a determinant of the community structure of epiphytic algae

Methods

Results

Conclusion