Journal of Ecology and Rural Environment ›› 2016, Vol. 32 ›› Issue (5): 826-831.doi: 10.11934/j.issn.1673-4831.2016.05.021

Previous Articles     Next Articles

Impact of Combined Cyhalothrin-Cd Pollution on Soil Microbes and Bioavailability of Cd

LI Jie, ZHANG Si-fan, XIAO Lin   

  1. School of Environment/State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, Nanjing 210023, China
  • Received:2015-08-19 Online:2016-09-25 Published:2016-10-08

Abstract:

To assess the joint impact of cyhalothrin and cadmium on soil microbial activity and bioavailability of Cd, soil samples were collected from a polluted field for analysis of changes in microbial biomass, respiration, enzymatic activity, pollution induced community tolerance (PICT), as well as bioavailability of Cd. For determining the latter two indices, the isotope-labeling and DGT (diffusive gradients in thin-films) technologies were used. Results show that soil respiration rate increased when 2 mg·kg-1 Cd was amended into the soil, but decreased when 10 mg·kg-1 Cd was. The amendment of both cyhalothrin and a low level of Cd stimulated soil biomass and respiration. Soil catalase, urease and alkaline phosphatase responded differently in activity to Cd and cyhalothrin. Urease was inhibited by Cd and revived to some extend when cyhalothrin was added, whilst alkaline phosphatase was inhibited in the initial 30 days and revived till the 60th day. The pollution of cyhalothrin alone did not show any PICT effect, however, the combined pollution elevated PICT to Cd, as well as bioavailability of Cd represented by DGT concentration. All the findings suggest that Cd in the combined pollution plays an essential role in affecting the studied indices, but the stimulating effects on soil microbial activity are synergistic ones when pyrethroidis coupled with a low level of Cd. CHT could increase PICT to Cd as well as bioavailability of Cd, which should be considered in the issue of food safety.

Key words: cadmium, cyhalothrin, combined pollution, soil microbe, bioavailability

CLC Number: