248MHALA

2770

6 janvier 2021 16:24

6 janvier 2021 16:24

A three year field study (2007–2009) of the diversity and numbers of the total and metabolically active free-living diazotophic bacteria and total bacterial communities in organic and conventionally managed agricultural soil was conducted using the Nafferton Factorial Systems Comparison (NFSC) study, in northeast England. Fertility management appeared to have little impact on both diazotrophic and total bacterial communities. However, copy numbers of the nifH gene did appear to be negatively impacted by conventional crop protection measures across all years suggesting diazotrophs may be particularly sensitive to pesticides. Impacts of crop management were greatly overshadowed by the influence of temporal effects with diazotrophic communities changing on a year by year basis and from season to season. Quantitative analyses using qPCR of each community indicated that metabolically active diazotrophs were highest in year 1 but the population significantly declined in year 2 before recovering somewhat in the final year. The total bacterial population in contrast increased significantly each year. It appeared that the dominant drivers of qualitative and quantitative changes in both communities were annual and seasonal effects. Moreover, regression analyses showed activity of both communities was significantly affected by soil temperature and climatic conditions.

None

• AB - Modalité bio
• FREDO adaptation aux changements globaux
• FREDO biologie et travail du sol
• FREDO fertilisation
• GEO Royaume-Uni
• bacterial communities
• climat
• comparaison
• management

PLoS ONE

7

e52891

2012-12-28

28 décembre 2012

10.1371/journal.pone.0052891 Le DOI est une URL unique de référencement d'une publication. Il est donc plus fiable et permanent qu'une URL classique

1932-6203 L’ISSN est un code de 8 chiffres servant à identifier les journaux, revues, magazines, périodiques de toute nature et sur tous supports, papier comme électronique.