Responses difference analysis of soil potential nitrification rates to Cu and sulfadiazine

Abstract

To investigate responses difference of soil potential nitrification rates (PNR) to heavy metals and antibiotics, batch toxicity experiments of Cu and sulfadiazine (SDZ) were conducted in four typical soils which were collected from different locations of China. Toxic differences of Cu and SDZ to soil PNR were evaluated based on their values of EC 20 and EC 50 calculated with logistic model. It was found that soil nitrification was a good indicator of Cu contamination in soils except for paddy soil. For SDZ, their EC X values were significantly higher than its concentration level (0.002~0.760 mg·kg -1 ) in soils. Thus, it was concluded that soil nitrification might be more sensitive to Cu than SDZ in field soil. The further Pearson correlation analysis indicated that the response of soil PNR to Cu and SDZ contamination were significantly related with soil PNR 0 and pH. ARTICLE HISTORY

The dependent correlation between soil multifunctionality and bacterial community across different farmland soils

“…Soil potential nitrification rate (PNR) was measured according to the method described by Liao et al (2019) . Briefly, 20 g soil was spiked with 0.044 M (NH 4 ) 2 SO 4 with a final concentration of 100 mg NH 4 + -N/kg soil and then adjusted its humidity to 60% of the WHC followed by a next incubation of 14 days at 25 ± 2°C.…”

Effects of sulfadiazine and Cu on soil potential nitrification and ammonia-oxidizing archaea and bacteria communities across different soils

“…The cation exchange capacity (CEC) was measured by analyzing the concentration of exchangeable cations in ammonium acetate extract of soils with an inductively coupled plasma-atomic emission spectrometry (ICP-AES, Optima 5300DV, Perkin Elmer). Cu in soils was determined with an inductively coupled plasma atomic emission spectrometer (ICP-MS, Vista MPX, United States, Varian) after digested by HCl, HNO 3 , and HF (8 ml, 3:9:4 v1/v2/v3) in a microwave digestion system (ETHOS 1, Italy, Milestone; Hu et al, 2011 ; Liao et al, 2019a , b ). For the analysis of SDZ in soil, the method of Zhou A. et al (2014) was employed with a modification, and the detailed procedure was described in the previous report ( Liao et al, 2019a , b ).…”

“…Cu in soils was determined with an inductively coupled plasma atomic emission spectrometer (ICP-MS, Vista MPX, United States, Varian) after digested by HCl, HNO 3 , and HF (8 ml, 3:9:4 v1/v2/v3) in a microwave digestion system (ETHOS 1, Italy, Milestone; Hu et al, 2011 ; Liao et al, 2019a , b ). For the analysis of SDZ in soil, the method of Zhou A. et al (2014) was employed with a modification, and the detailed procedure was described in the previous report ( Liao et al, 2019a , b ).…”

“…At the end of 7 days’ pre-incubation, the soils were spiked with SDZ and CuSO 4 , respectively, to their designed concentrations. Then, all soils were thoroughly mixed, and each soil treatment was split into two subsamples: a subsample amended with 100 mg NH 4 -N/kg fresh soil using a stock solution of (NH 4 ) 2 SO 4 and additional deionized water to reach soil moisture of 60% of WHC for soil potential nitrification rates (PNRs) analysis according to the ISO method ( Rusk et al, 2004 ) with slight modification, seen in our prior publications ( Liu et al, 2014 ; Liao et al, 2019a , b ); another one, used for the amoA gene analysis, was humidified directly with deionized water to 60% of WHC and incubated for another 14 days to keep the same incubating days with soil PNR. During the whole incubation, soil moisture was maintained at 60% of WHC by adding regularly sterilized ultra-pure water.…”

“…In light of the pivotal roles in the nitrogen cycling of ecosystems ( Falkowski et al, 2008 ; Ke et al, 2013 ; Wang et al, 2015 ), ammonia-oxidizing microorganisms and the compounding function were widely chosen as biomarkers of soil environmental contamination ( Katipoglu-Yazan et al, 2016 ; Zhang et al, 2017 ; Wei et al, 2018 ). It was found that combined exposure to antibiotics and heavy metals caused stronger toxicity than the single one on ammonia-oxidizers’ abundance and nitrification activity ( Liao et al, 2019a , b ; Wang L. et al, 2019 ). The abundant data also indicated that the entered toxicant could alter soil microbial activity ( Gil-Sotres et al, 2005 ; Hammesfahr et al, 2011 ; Cycoń et al, 2016 ) and then shift their community structure ( Wang L. et al, 2019 ).…”