Distribution Pattern and Diversity Maintenance Mechanism of the Denitrifier Community in Alkaline Copper Mine Drainage

Abstract

Denitrifiers have been shown to vary in abundance and diversity across the environmental gradients; 6 however, the factors that determine the type and magnitude of the response of the denitrifier communities remain unclear. 7In order to reveal the effects of alkaline mine drainage (AlkMD) on the denitrifier community composition and diversity 8 maintenance mechanism in a tailings reservoir, we examined the diversity patterns and adaptation mechanisms of 9 different denitrifier communities in Shibahe copper tailings water in Zhongtiaoshan, China. The results showed that the 10 α-diversity of Proteobacteria and the nosZ І -bearing denitrifier community in downstream seeping water (SDSW) were 11 the highest, while those in the upstream tailings water (STW1) were the lowest. The highest nirS and nirK-bearing 12 denitrifier community α-diversity were measured in STW1, and the lowest in STW3. The community dissimilarity of the 13 denitrifier communities was strongly correlated with environment parameters, but the factors varied in different groups. 14 The Proteobacteria community was correlated strongly with nitrate (NO 3 -); the nirS and nirK-bearing denitrifier 15 communities were correlated strongly with pH, total carbon (TC), NO 3 and ammonia nitrogen (NH 4 + ), and the 16 nosZ І -bearing denitrifier community was correlated strongly with total organic carbon (TOC), dissolved oxygen (DO), 17 NO 3 -, electroconductibility (EC) and spatial distance (PCNM1). Our results indicated that environmental changes were 18 valuable index reflecting variations in denitrifier community composition in AlkMD. Additionally, the findings in this 19 study are helpful in understanding the relationship between the microbial community composition changes and 20 functional adaptation in different ecosystems. (B. Chai).2 IMPORTANCE Metal mine tailings pond is an important site polluted by heavy metals and nitrogen, and excess 22 nitrogen is mainly removed by microorganisms through denitrification. Although many studies have reported that 23Proteobacteria is the main denitrifying bacteria, and nirS, nirK and nosZ-bearing denitrifiers are three key functional 24 groups in denitrification process. However, less is known of their response to discharge of alkaline copper tailings 25 wastewater (AlkMD). AlkMD exerts an adverse impact on composition and structure of denitrifying bacteria community. 26The change of nitrogen and carbon concentration along the flow direction of wastewater resulted in the change of 27 denitrifying bacteria community diversity pattern, that is to say, environmental filtering force drove the denitrifier 28 community structure in this highly polluted ecosystem. 29

Comparative Analysis of Fungal Diversity and Community Structure of Different Volcanic Soils in Wudalianchi, China

“…In this study, Basidiomycota and Ascomycota are the dominant fungi communities of soil fungi in Wudalianchi, and their abundance in the NV is 98.01%-98.98%. The new volcanic lava platform is featured by less water and good permeability, which are consistent with the characteristics of Basidiomycetes and Ascomycetes that prefer soil permeability (Liu et al 2019). However, the abundances of Basidiomycetes, Ascomycetes, Rozellomycota, and unknown fungi community in the three plots are significantly different.…”

The Impact of Plant Spatial Patterns on Nitrogen Removal in the Naolihe Wetlands of Northeast China

“…Juncus effusus showed a greater nitrogen removal capacity than Calluna vulgaris and sphagnum mosses, where the spatial pattern of nitrogen removal showed a decreasing trend from the deep-water area along the river channel to the shallow-water area along the shore in the wetlands in the upper, southern area of the Conwy catchment, North Wales, UK [22]. The significant spatial heterogeneity of Nymphaea tetragona and Vallisneria natans led to spatial differences in NH 4 -N concentration, and the spatial distribution of nitrogen removal in water bodies was controlled by the distribution trend of the plants [23]. The plant spatial allocation in the lakeside zone of Yunnan Plateau wetlands varied, and there was a significant spatial difference in the nitrogen removal ability of wetland water [24].…”