Warming Effects on Periphyton Community and Abundance in Different Seasons Are Influenced by Nutrient State and Plant Type: A Shallow Lake Mesocosm Study

Abstract

Frontiers in Plant Science | www.frontiersin.org April 2020 | Volume 11 | Article 404 Hao et al.Warming Effects on Periphyton in spring, summer, and autumn. Our results suggest that the effect of warming on periphyton abundance and composition in the different seasons varied with nutrient state and host plant type in these mesocosms, and similar results may likely be found under field conditions.

Seasonality and Species Specificity of Submerged Macrophyte Biomass in Shallow Lakes Under the Influence of Climate Warming and Eutrophication

“…On the other hand, the rapid development of agriculture and industrialization has led to massive inputs of nutrients, especially nitrogen (N) and phosphorus (P), in aquatic environments (Tilman et al, 2001). It has been suggested that the alteration of temperature and nutrient availability will change the ecosystem structure and thereafter threaten the ecological functioning of shallow lakes (Liboriussen et al, 2005;Özkan et al, 2010;Kosten et al, 2012;Hao et al, 2020). Submerged macrophytes are an important component in aquatic ecosystems and usually play a vital role in the ecological functioning of shallow lakes (Jeppesen et al, 2012;Hao et al, 2017).…”

“…However, Hao et al (2018) and Jones et al (2002) suggested that temperature and nutrients might regulate the growth of submerged macrophytes through the indirect pathway by which rising temperature and nutrient enrichment could induce environmental stress and then cause a decline in the biomass of submerged macrophytes. Furthermore, rising temperature and nutrient enrichment could change abiotic variables, such as dissolved oxygen (DO) and pH, and, thus, influence submerged macrophytes, because DO is necessary for respiration, and pH can determine the availability of inorganic carbon (C) for submerged macrophytes (Jones et al, 2002;Zhang et al, 2015;Dülger et al, 2017;Hao et al, 2020). On the other hand, temperature and nutrients could affect submerged macrophytes through effects on biotic variables, such as the biomass of phytoplankton, periphyton, and zooplankton, since stress from the same trophic level and higher trophic levels may threaten the growth of submerged macrophytes (Jones et al, 2002;Ventura et al, 2008;Hao et al, 2018;Matsuzaki et al, 2018;Yuan and Pollard, 2018).…”

“…Taking the life history of an organism into account, seasonality may play a key role in the growth of submerged macrophytes under the influence of rising temperature and nutrient enrichment (Staehr and Sand-Jensen, 2006;Trochine et al, 2014;Zhang et al, 2019;Fu et al, 2020;Hao et al, 2020). For example, Riis et al (2012) suggested that some submerged macrophyte species were controlled by high summer temperatures rather than low winter temperatures.…”

“…For example, Riis et al (2012) suggested that some submerged macrophyte species were controlled by high summer temperatures rather than low winter temperatures. Hao et al (2020) found that low temperatures and lower light availability in winter created a harsh environment for primary producers and stressed changes in explanatory variables. However, the experimental cycle in similar studies has usually lasted only dozens of days or one season (Olesen and Madsen, 2000;Riis et al, 2012;Velthuis et al, 2017;Hao et al, 2018;Zhang et al, 2020), which has precluded observation of the response of submerged macrophytes to rising temperature and nutrient enrichment based on the seasonal scale, as well as determination of the main explanatory variables in each season.…”

“…history and morphological structure are conspicuously distinct between P. crispus and E. canadensis (Nichols and Shaw, 1986;Hao et al, 2020). Specifically, P. crispus has a thick branching stem accompanied with sparse strip leaves, while E. canadensis has a thin branching stem accompanied by dense whorled leaves (Figure 1).…”