title: Influence of temperature on phenanthrene toxicity towards nitrifying bacteria in three soils with different properties.
abstract: This study focused on the combined effect of environmental conditions (temperature) and contamination (polycyclic aromatic hydrocarbons, PAHs) on the activity of soil microorganisms (nitrifying bacteria). Phenanthrene (Phe) at five contamination levels (0, 1, 10, 100 and 1000 mg kg(-1) dry mass of soil) was employed as a model PAH compound in laboratory experiments that were conducted at three temperatures (i.e., 20 °C (recommended by ISO 15685 method), 15 and 30 °C). Three soils with different properties were used in these studies, and the activity of the nitrifying bacteria was assessed based on nitrification potential (NP) determinations. For the statistical evaluation of the results, the ANCOVA (analysis of covariance) method for three independent variables (i.e., temperature, phenanthrene concentration, soil matrix (as a qualitative variable)) and their interactions was employed. The results indicated on the significant interaction of all studied factors. Temperature influenced the toxicity of Phe towards NP, and this effect was related to the Phe concentration as well as was varied for the different soils. A low content of soil organic matter (controlling bioavailability of phenanthrene to soil microorganisms) enhanced the combined effect of temperature and Phe toxicity, and a high biological activity of the soil (high NP values) increased the effect of high temperature on the Phe stimulatory influence. The results indicate that the temperature should not be neglected in tests evaluating PAH ecotoxicity, especially for reliable ecological risk assessment.
authors.affiliation: Institute of Soil Science and Plant Cultivation - State Research Institute (IUNG-PIB), Czartoryskich 8, 24-100 Pulawy, Poland. Electronic address: bsuszek@iung.pulawy.pl.
authors.forename: Beata
authors.initials: B
authors.lastname: Suszek-Łopatka
authors.affiliation: Institute of Soil Science and Plant Cultivation - State Research Institute (IUNG-PIB), Czartoryskich 8, 24-100 Pulawy, Poland. Electronic address: bkord@iung.pulawy.pl.
authors.forename: Barbara
authors.initials: B
authors.lastname: Maliszewska-Kordybach
authors.affiliation: Institute of Soil Science and Plant Cultivation - State Research Institute (IUNG-PIB), Czartoryskich 8, 24-100 Pulawy, Poland. Electronic address: agnes@iung.pulawy.pl.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Klimkowicz-Pawlas
authors.affiliation: Institute of Soil Science and Plant Cultivation - State Research Institute (IUNG-PIB), Czartoryskich 8, 24-100 Pulawy, Poland. Electronic address: bozena@iung.pulawy.pl.
authors.forename: Bożena
authors.initials: B
authors.lastname: Smreczak
mesh_terms: D001419:Bacteria / Q000187:drug effects; D001682:Biological Availability; D008962:Models, Theoretical; D009586:Nitrogen Fixation / Q000187:drug effects*; D010616:Phenanthrenes / Q000032:analysis / Q000633:toxicity*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*; D013557:Switzerland; D013696:Temperature
chemical_list: D010616:Phenanthrenes; D012987:Soil; D012989:Soil Pollutants; C031181:phenanthrene
keywords: Interactions modelling; Joint effect of chemical and natural factors; Nitrification potential; PAH toxicity