Soil specialist from the UACh completed a research internship at the BOKU Institute of Soil Research in Vienna, Austria

Dr. John Clunes completed a research internship with Dr. Katharina Keiblinger and Dr. Rebecca Hood-Nowotny from the Institute of Soil Research, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences Vienna (BOKU) in Vienna, Austria.

By Lorenzo Palma, Journalist.- From December 2022 to March 2023, the Adjunct Professor of the Institute of Agricultural and Soil Engineering of the Faculty of Agricultural and Food Sciences of the Austral University of Chile (UACh) carried out a research stay at BOKU.

The University of Natural Resources and Life Sciences (BOKU) in Vienna is dedicated to teaching and research in the field of sustainability and management. In this place, Dr. Clunes made the stay, within the framework of his FONDECYT Initiation project “Physical storage of nutrients in the volume of the pores. A dynamic factor of nutrient availability that depends on the soil structure and microbial biomass”.

Dr. Clunes set out the objective of determining the turnover of microbial biomass, the stoichiometric proportions of C and N in the microbial biomass of the soil and its effect on the availability of nutrients in the pore volume of five soils derived from ash. volcanic under permanent grasslands.

Until Vienna, the researcher took samples of five different soils derived from volcanic ash located in the Los Ríos and Los Lagos regions, in southern Chile. “All the soils were under the same management condition: permanent natural grasslands without nutrient inputs from fertilizers during the last 5 years” explained Dr. Clunes.

The academic says that he chose Boku for an experience in 2018, when he did a research internship for his doctorate. “During that time, I had the opportunity to collaborate with Dr. Katharina Kieblinger, a leading expert in soil biology, in the development of the second chapter of my doctoral thesis. I was impressed by her broad resume and her deep knowledge of the field. After that, a cooperation agreement was established between both institutions. Furthermore, the research areas of Dr. Katharina Kieblinger are Soil Biogeochemistry, C-Sequestration in soils, Soil Microbiology, N-cycling in soils and soil contamination. On the other hand, Dr. Rebecca Hood-Nowotny works on stable isotopes in agroecosystems, nutrient cycling and nutrient use efficiency”.

John Clunes was in charge of preparing the samples used in the study. After collecting them in the field, they were stored at a temperature of 4 °C until shipment to Vienna. Once in Vienna, controlled incubation was carried out for 16 days, maintaining adequate temperature and humidity. Prior to incubation, labeled Glucose (13C) and labeled Ammonium Sulfate (15N) were added to the samples. During incubation, samples were collected to measure various parameters, including microbial biomass, CO2 emission (respiration), enzyme activity, DNA extraction, soluble soil carbon, and soil mineral nitrogen.

With the internship completed, Dr. Clunes explains that it is expected to determine the presence of a biological pool in volcanic soils and what is its participation in the availability of Nitrogen. “What I highlight the most is the excellent availability of Kathi and Rebecca to carry out the research, in addition to my colleagues and friends who received me in Boku.

In the southern region of Chile, the professor from the Austral University of Chile (UACh) points out the presence of various types of volcanic soils between the foothills of the Andes and the coastal mountain range, due to their formation processes. Among them are sandy-loam soils of the Puyehue series, classified as Inceptisols. Soils from fluvial terraces of loam-clay-silt composition can also be found, belonging to the Río Bueno series, of the Inceptisol-Andico type. In addition, there are transitional soils that have a loam-clay-silt texture, belonging to the Los Ulmos series, classified as Ultisols. Likewise, there are red clayey soils, with a loamy-clay texture, classified as soils of the Cudico series, also belonging to the Ultisols. Finally, the trumao soils with a loamy-silty texture are mentioned, from the Valdivia series, classified as Andisols.