Reduced tillage stimulated symbiotic fungi and microbial saprotrophs, but did not lead to a shift in the saprotrophic microorganism community structure

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

The need for sustainable agricultural systems, which for example enhance soil organic carbon (SOC) content, has increased the interest for management with reduced tillage. In this study we used a Swedish long-term (20 yrs.) systems experiment, including reduced tillage (harrowing 10 cm) and plowing (moldboard plow 0–20 cm) combined with three levels of nitrogen (N) fertilization. With this setup we tested if (1) the arbuscular mycorrhizal fungi (AMF) concentration and (2) the fungi to bacteria (F:B) ratio would be higher under reduced tillage than under conventional tillage, and if this would be associated with higher SOC concentrations. We also tested if (3) the microbial biomass C close to the surface would be higher under reduced tillage than conventional tillage. Furthermore, since disturbance can reduce respiration and microbial growth we tested if (4) this occurred in our reduced tillage system. In addition, we tested if (5) fertilization increased the growth rate of fungi and decreased that of bacteria. We collected soil samples in July and October and found that the microbial biomass C, measured in October only, was higher close to the surface in the reduced tillage treatment and so was the microbial respiration. The fungal and bacterial growth rate, on the other hand, were not affected by tillage treatment. Fertilization did not affect the bacterial growth rate but did have a positive effect on fungal growth rate. In accordance with our expectations reduced tillage had a stimulating effect on AMF and saprotrophic fungi, and contrary to our expectation, also bacteria were positively affected by reduced tillage. In line with the unchanged F:B ratio, we found no indication that even 20 years of reduced tillage increased SOC concentrations in the long term.

Detaljer

Författare
Enheter & grupper
Externa organisationer
  • Swedish University of Agricultural Sciences
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Miljö- och naturvårdsvetenskap
  • Ekologi

Nyckelord

Originalspråkengelska
Sidor (från-till)104-114
Antal sidor11
TidskriftApplied Soil Ecology
Volym119
StatusPublished - 2017 okt 1
PublikationskategoriForskning
Peer review utfördJa

Relaterad forskningsoutput

Sofia Hydbom, 2017 nov, Lund: Lund University, Faculty of Science, Centre for Environmental and Climate research (CEC) & Department of Biology. 140 s.

Forskningsoutput: AvhandlingDoktorsavhandling (sammanläggning)

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