Microbial-driven carbon fixation in natural wetland

Interplay of soil characteristics and arbuscular mycorrhizal fungi diversity in alpine wetland restoration and carbon stabilization

Alpine wetlands are critical ecosystems for global carbon (C) cycling and climate change mitigation. Ecological restoration projects for alpine grazing wetlands are urgently needed, especially due to their critical role as carbon (C) sinks. However, the fate of the C pool in alpine wetlands after restoration from grazing remains unclear. In this study, soil samples from both grazed and restored wetlands in Zoige (near Hongyuan County, Sichuan Province, China) were collected to analyze soil organic carbon (SOC) fractions, arbuscular mycorrhizal fungi (AMF), soil properties, and plant biomass. Moreover, the Tea Bag Index (TBI) was applied to assess the initial decomposition rate (k) and stabilization factor (S), providing a novel perspective on SOC dynamics. The results of this research revealed that the mineral-associated organic carbon (MAOC) was 1.40 times higher in restored sites compared to grazed sites, although no significant difference in particulate organic carbon (POC) was detected between the two site types. Furthermore, the increased MAOC after restoration exhibited a significant positive correlation with various parameters including S, C and N content, aboveground biomass, WSOC, AMF diversity, and NH4+. This indicates that restoration significantly increases plant primary production, litter turnover, soil characteristics, and AMF diversity, thereby enhancing the C stabilization capacity of alpine wetland soils.

Revealing viral diversity in the Napahai plateau wetland based on metagenomics

We focused on exploring the diversity of viruses in the Napahai plateau wetland, a unique ecosystem located in Yunnan, China. While viruses in marine environments have been extensively studied for their influence on microbial metabolism and biogeochemical cycles, little is known about their composition and function in plateau wetlands. Metagenomic analysis was employed to investigate the viral diversity and biogeochemical impacts in the Napahai wetland. It revealed that the Caudoviricetes and Malgrandaviricetes class level was the most abundant viral category based on phylogenetic analysis. Additionally, a gene-sharing network highlighted the presence of numerous unexplored viruses and demonstrated their unique characteristics and significant variation within the viral community of the Napahai wetland. Furthermore, the study identified the auxiliary metabolic genes (AMGs). AMGs provide phages with additional functions, such as protection against host degradation and involvement in metabolic pathways, such as the pentose phosphate pathway and DNA biosynthesis. The viruses in the Napahai wetland were found to influence carbon, nitrogen, sulfur, and amino acid metabolism, indirectly contributing to biogeochemical cycling through these AMGs. Overall, the research sheds light on the diverse and unique viral communities in the Napahai plateau wetland and emphasizes the significant roles of viruses in microbial ecology. The findings contribute to a deeper understanding of the characteristics and ecological functions of viral communities in plateau wetland ecosystems.