Effect of Storage, Drying and Conditioning of Forest Soils on the Phospholipid Fatty Acid Profiles of the Soil Microbial Community

Wien

Österreichische Bodenkundliche Gesellschaft

2005

S. 28

Artikel aus einer ZeitschriftUnselbständiges Werk

200123324

Soil Indicators : Annual meeting of the Austrian Soil Science Society 12th and 13th May 2005, Ljubljana : Programme : Book of Abstracts, S. 28

Soil sampling, sample transport, sample storage and sample preparation are one of the key procedures in the course of soil monitoring programs or soil inventories. Special requirements exists when soil microbial parameters should be investigated. The need for a rapid conservation of the actual biological status as well as a fast transport to the laboratory are demands which are not accomplishable due to remote sites and difficult terrain especially within forest soil monitoring programs or and inventories. The environmental policy asks for status data and the development trend of the microbial divesity in soils. Until now no parameters were used in soil inventory and or soil monitoring programs to characterize the soil microbial community. In this work we investigated the influence of different storage and drying conditions and the effect of a reconditioning step on the quantitative and qualitative results of the Phospholipid Fatty Acid profiles of the soil microbial community in forest soil samples. The soil samples were taken in October 2003 and June 2004 at three WBZI - sites. The sites were located at Klausenleopoldsdorf (Dystric Cambisol, pH=4,1), Aigen near Baden (Rendzina, pH=7,4) and Aspang (Gleyic Podzol, pH=3,5). Samples were taken from the mineral soil horizon at the depth of 0-5 cm and 5-10 cm. The samples were transported chilled at the same day to the laboratory. After sieving <2mm from one part of the sample PLFAs were analysed as a reference immediately. The remaining soil was divided in three parts with different drying and storage conditions. One part was dried at 40°C in an drying oven, one was air dried and one was leaved for two weeks in a plastic bag and was subsequently air dried (delayed drying). After this different drying procedures the soil samples were adjusted to 50% of the maximum water holding capacity and were incubated at 15°C for two weeks. After one and two weeks of reconditioning, subsamples were analysed for PLFAs. Further the samples were characterised by chemical and physical soil parameters. Drying and reconditioning cause a significant decrease of the fungi marker fatty acid 18:26 and an increase of the unspecific fatty acid 16:0 and 18:0. This trend was reproducible for all sites and both sampling dates. In spite of theses changes the three sites could be differentiated by the PLFA composition independent of the drying procedure.