Microflora of Surface Layers in Aquatic Environments and Its Usage

Abstract

Periphytic biofilm, also known as periphyton, which is a microflora aggregate composed of heterotrophic and autotrophic microorganisms, such as microalgae, bacteria, fungi, and protozoa, ubiquitously grows at the interface of water and soil/ sediment of almost every aquatic ecosystem ranging from small ponds to large oceans, also including paddy fields (Wu 2016; Sun et al. 2021). It well reflects a critical vision of the Sustainable Development Goals that employing the ubiquitous periphytic biofilm in water discharge systems due to its characteristics of environment friendly and functional diversity. Periphytic biofilm has shown potential in entrapping nutrients, removing heavy metals, degrading organics, controlling harmful algal blooms, and so on. Taking advantages of periphytic biofilm, it may play a huge role in treating pollutants in water discharge systems.

Geographic imprint and ecological functions of the abiotic component of periphytic biofilms

“…Microorganisms are the main producers and consumers of the EPS component in periphytic biofilms; their activity will directly change the composition and content of EPS in periphytic biofilms [9]. Here we found that the microbial community of periphytic biofilms grown in paddy fields is different from those grown in natural aquatic ecosystems, which are largely dominated by various phototrophic algae [18]. Periphytic biofilms growing in paddy fields are mainly dominated by chemotrophic microorganisms, which may be a result of the abundant supply of nitrogen and phosphorus, and limited light caused by rice canopy shading.…”

“…Therefore, maybe certain climatic factors would lead to the decreased synthesis of EPS by periphytic biofilms, resulting in the difference in the EPS content in periphytic biofilms grown in different rice planting areas. In addition, it is well known that climatic factors, such as lighting and temperature, can affect the growth of microbes thus shifting the microbial community structure in periphytic biofilms [4,18]. As prokaryotes and eukaryotes potentially showed different roles in the EPS content in periphytic biofilms, thus the climate-induced difference in the structures of prokaryotes and eukaryotes in different periphytic biofilms (cf.…”

Periphytic biofilms function as a double‐edged sword influencing nitrogen cycling in paddy fields

“…Microbes play key roles in the biogeochemistry of N in the environment (Mushinski et al, 2021; Wang et al, 2020); thus, their potential to intercept N loss and enhance N utilization efficiency is attracting increasing attention (Antonopoulos, 2010; Mooshammer et al, 2014). In nature, microorganisms usually grow in the form of microbial aggregates (Guilhen et al, 2017; Kim & Lee, 2016); for instance, periphytic biofilms are native and ubiquitous microbial aggregates in paddy fields (Sun, Gao, & Wu, 2021).…”