title: The impact of agricultural soil usage on activity and abundance of ammonifying bacteria in selected soils from Poland.
abstract: The aim of the study was to demonstrate the impact of soil agricultural usage on the abundance of ammonifying bacteria (AB) and their activity, expressed as arginine ammonification (AA). Five agriculturally exploited types of soils (FAO): Haplic Luvisol, Brunic Arenosol, Mollic Gleysol, Eutric Fluvisol, and Rendzina Leptosol were studied. The controls were non-agricultural soils of the same type located in close proximity to agricultural sites. The tested soils varied in terms of pH (4.18-7.08), total carbon (8.39-34.90 g kg(-1)), easily degradable carbon content (0.46-1.11 g kg(-1)), moisture (5.20-13.50 %), and nitrogen forms (mg kg(-1)): 1.68-27.17, 0.036-0.862, 0.012-3.389 for nitrate nitrogen, nitrite nitrogen, and ammonia nitrogen, respectively. The AB abundance in agricultural soils ranged from 1.1 to 6.4 × 10(4) cfu g(-1), while in the controls it was significantly higher-from 2.0 to 110 × 10(4) cfu g(-1) of soil. Also, AA in the controls was three-times higher than in the agricultural soils. Strong associations between AA and the abundance of AB in the control (r = 0.954***) and agricultural soils (r = 0.833***) were proved. In the agricultural soils, the AB abundance and AA were influenced by pH (r = 0.746*** and r = 0.520***) and carbon content (r = 0.488*** and r = 0.391***). The AB abundance was also affected by easily degradable carbon (r = 0.517**) and nitrite nitrogen (r = 0.376*), whilst ammonium nitrogen influenced AA (r = 0.451*). Our results indicate that the abundance of AB and AA may be good indicators of soil biological conditions.
authors.affiliation: Department of Biochemistry and Environmental Chemistry, Institute of Biotechnology, The John Paul II Catholic University of Lublin, Konstantynów 1 I Str., 20-708 Lublin, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Wolińska
authors.affiliation: Department of Biochemistry and Environmental Chemistry, Institute of Biotechnology, The John Paul II Catholic University of Lublin, Konstantynów 1 I Str., 20-708 Lublin, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Szafranek-Nakonieczna
authors.affiliation: Department of Biochemistry and Environmental Chemistry, Institute of Biotechnology, The John Paul II Catholic University of Lublin, Konstantynów 1 I Str., 20-708 Lublin, Poland.
authors.forename: Artur
authors.initials: A
authors.lastname: Banach
authors.affiliation: Department of Microbial Biology, Warsaw University of Life Sciences, 159 Nowoursynowska, Str., 02-776 Warsaw, Poland.
authors.forename: Mieczysław
authors.initials: M
authors.lastname: Błaszczyk
authors.affiliation: Department of Biochemistry and Environmental Chemistry, Institute of Biotechnology, The John Paul II Catholic University of Lublin, Konstantynów 1 I Str., 20-708 Lublin, Poland.
authors.forename: Zofia
authors.initials: Z
authors.lastname: Stępniewska
keywords: Agricultural soil usage; Ammonifying bacteria; Arginine ammonification; Nitrogen forms; pH