Soil Microbial Abundances and Enzyme Activities in Different Rhizospheres in an Integrated Vertical Flow Constructed Wetland

Abstract

Rhizosphere microorganism is an important bio-component for wastewater treatment in constructed wetlands (CWs). Microbial abundance and enzyme activities in the rhizospheres of nine plant species were investigated in an integrated vertical-flow CW. The abundance of denitrifiers, as well as urease, acid, and alkaline phosphatase activities were positively correlated to plant root biomass. The abundance of bacteria, fungi, actinomycetes, ammonifiers, denitrifiers, and phosphorus decomposers, related to nutrient removal efficiencies in CWs, greatly varied among rhizospheres of different plant species (p < 0.05). Significant differences in rhizosphere enzyme activity among plant species were also observed (p < 0.05), with the exception of catalase activity. The principal component analysis using the data of microbial abundance and enzyme activity showed that Miscanthus floridulus, Acorus calamus, and Reineckia carnea were candidates to be used in CWs to effectively remove nitrogen and phosphorus from wastewater.

The Runoff Declining Process and Water Quality in Songhuajiang River Catchment, China under Global Climatic Change

“…Decrease runoff in these two sub-catchments then results in runoff decrease in Mainstream of Songhuajiang catchment. The above results provide better basis for protecting water quality and environmental policy-makers [32][33][34]. …”

“…Also in the plain area of Haihe catchment, farming styles increased the agricultural water use and thus decrease the runoff [32,33]. Soil and water conservation measures also have significant effects on runoff decline [32][33][34].…”

Spatio-temporal variation of rhizosphere soil microbial abundance and enzyme activities under different vegetation types in the coastal zone, Shandong, China

“…In the present study, phosphatase activity of rhizosphere soils under P. thunbergii showed higher values compared with those from soils under the other species, which could attribute to the increased adsorption of inorganic phosphorous or depletion of available phosphorous by their roots (Garcia et al 2005). The results mentioned above, on one hand, might be, in part, due to the substrate availability for these enzymes, and on the other hand, might be related to different contributions of plant enzymes to total enzyme activities (Ge et al 2011). In addition, urease and phosphatase activities were lower significantly compared with other study (Ge et al 2011), which could attribute to low water content of coastal sandy soils.…”

“…The results mentioned above, on one hand, might be, in part, due to the substrate availability for these enzymes, and on the other hand, might be related to different contributions of plant enzymes to total enzyme activities (Ge et al 2011). In addition, urease and phosphatase activities were lower significantly compared with other study (Ge et al 2011), which could attribute to low water content of coastal sandy soils. Changing enzyme activities in soils submitted to low water potential may indicate that drought changes rhizode position, root litter production, and ultimately substrate availability (Sanaullah et al 2011).…”

Plant Species Richness Affected Nitrogen Retention and Ecosystem Productivity in a Full‐Scale Constructed Wetland

“…However, substrate nitrate concentration was positively correlated with SR under high N input in this study. This may be due to (1) plant SR had positive effects on microbial biomass carbon and N in the rhizosphere [18], for the diverse roots could increase the release of exudates [27], the availability of oxygen in the substrate and microbial activities and nutrient cycling in the CW [23,28], (2) higher root production in communities with higher plant SR would increase nitrate accumulation through filtering functions [2], and (3) substrate nitrate concentration did not decrease though plant N uptake due to continuous N input from the CW. Therefore, plant communities with higher SR had higher nitrate concentrations in the substrate.…”