Refine
Year of publication
- 2021 (2)
Document Type
Language
- English (2)
Keywords
Institute
- FG Ökologie (2)
Agricultural management practices and extreme weather events associated with climate change can influence the diversity and abundance of arbuscular mycorrhizal fungi (AMF) with potential consequences for crop production. However, the importance of the interactive effects of long-term agricultural management and extreme weather events on AMF communities in agricultural soils is not yet fully explored. A short-term drought experiment with rainout-shelters was performed in winter wheat fields in a long-term agricultural trial with organic (biodynamic) and conventional management practices. During four months of the winter wheat growing period (March–June 2017), the rainout-shelters reduced the ambient precipitation by 65% on average. At two sampling dates, the AMF diversity and community composition were assessed using a single-molecule real-time (SMRT) DNA sequencing. A total of 955 amplicon sequence variants (ASVs), belonging to twelve genera were identified. The long-term farming systems and the short-term experimental drought did not affect AMF ASV diversity levels. The AMF community composition at the genus level differed between the organic and the conventional farming systems, but no distinctive communities were found in response to the experimental drought. The three most abundant genera Acaulospora, Paraglomus and Funneliformis were correlated to the two farming practices. Our study demonstrates that AMF communities in agricultural soils are responsive to long-term farming systems, and are resistant to one short-term summer drought event.
Conventional agriculture and not drought alters relationships between soil biota and functions
(2021)
Soil biodiversity constitutes the biological pillars of ecosystem services provided by soils worldwide. Soil life is threatened by intense agricultural management and shifts in climatic conditions as two important global change drivers which are not often jointly studied under field conditions. We addressed the effects of experimental short‐term drought over the wheat growing season on soil organisms and ecosystem functions under organic and conventional farming in a Swiss long term trial. Our results suggest that activity and community metrics are suitable indicators for drought
stress while microbial communities primarily responded to agricultural practices. Importantly, we found a significant loss of multiple pairwise positive and negative relationships between soil biota and process‐related variables in response to conventional farming, but not in response to experimental drought. These results suggest a considerable weakening of the contribution of soil biota to ecosystem functions under long‐term conventional agriculture. Independent of the farming system, experimental and seasonal (ambient) drought conditions directly affected soil biota and activity. A higher soil water content during early and intermediate stages of the growing season and a high number of significant relationships between soil biota to ecosystem functions suggest that organic farming provides a buffer against drought effects.