It is critical for environmental scientists to quantify the major sources and sinks of the most important greenhouse gases (GHGs), CO2, CH4 and N2O, as well as to disentangle the processes involved in GHG production and consumption in terrestrial ecosystems. Such data and knowledge are essential for the development of national and international strategies for improved/optimized land use and climate mitigation. The course aims to teach future researchers how to use the newest, manual and automated chamber technologies and state-of-the-art analytical tools for measuring and interpreting the GHG exchange between ecosystems and the atmosphere.

The chamber method is the most widely used for GHG flux measurements between ecosystems and the atmosphere: However, manual chamber measurements are time consuming, which hampers spatial and temporal data coverage and implementation of results in a larger context. Recent development in combining novel chamber designs with real-time GHG analyses now allows for automation of GHG flux measurements leading to a hundredfold increase in the number of measurements per unit of time. This technological development improves the temporal representation and resolution in data, in turn helping researchers to improve their understanding of the soil and ecosystem processes governing the exchange of greenhouse gases with the atmosphere at temporal and spatial scales previously out of reach. On the other hand, the much larger data sets produced with automated measurements also creates a need for automating data analytical procedures and quality control.

The course will focus on developing the skill set for post-graduate students in measuring and analyzing the exchange of GHG’s between the soil/ecosystem and the atmosphere using newest chamber technologies. The course will highlight the conceptual, technological and analytical challenges involved in obtaining the “true” measure of the GHG flux between an ecosystem and the atmosphere and how these data can be used to address fundamental knowledge gaps related to the processes involved in ecosystem GHG production and uptake and potential ecosystem feedback to climate and global changes.

Learning outcome

Knowledge:
• describe commonly used chamber methods and equipment for measuring greenhouse gas fluxes from soils
• demonstrate the field use of the chamber method
• discuss theory of sampling design

Skills:
• work independently with the chamber methods under field conditions
• evaluate the pros and cons of using specific designs to measure greenhouse gas fluxes
• apply the sampling methodology in the field
• design a problem-oriented scientific field sampling protocol for greenhouse gas fluxes

Competences:
• project-oriented group work in the field
• choose the correct techniques to obtain a representative flux of greenhouse gases in space and time
• analyze field data using graphic and statistical techniques (R software)
• synthesize results in a written report

Teaching and learning methods

The student prepares for the onsite course by reviewing current GHG flux literature prior to course start. The course preparation involves e-learning including pre-recorded lectures and a questionnaire, aimed to form the basis for an active involvement in the specific theoretical and methodological problems, how to construct a research question and carry out a field sampling design. During the course, students will be working with hands-on measurements at various field sites and in the lab using different manual and automated chamber measurement systems. The insights from the hands-on exercises will form the basis for classroom discussion and learning. Finally, the students will perform hands-on analytical work in the classroom using R software on the obtained data in combination with long-term data from automatic chambers.

Throughout the course, the teacher team presents lectures covering the central theoretical and practical aspects of the chamber methodology. Lectures interact with class instructions for the theoretical and practical exercises that are in focus on the course. The students will furthermore actively engage in the course by presenting their current PhD projects as well as through group work in theoretical exercises and fieldwork. The course ends with group presentations on a chosen topic covering both theoretical aspects and actual results obtained during the course. Each group further summarizes their work in a written report submitted no later than two weeks after the course presenting and discussing the collected data and results. The participants pass the course after approval of their written report no later than 2 weeks after submission.

Type of assesment

The course is finalized by a written report submitted max. 14 days after the course.

Guest lecturers
Johannes W.M. Pullens is assistant Professor at Dept. of Agroecology at Aarhus University. He is involved in the AnaEE Denmark research Infrastructure and works with both eddy covariance and chamber measurements to measure exchange of CO2, N2O and CH4 of agrosystems. He will contribute with lectures in lecture room and in the field as well as to practical exercises throughout the week of the course.

Sander Bruun (assoc prof) and Azeem Tariq (assist prof) from Dept. of Plant and Environmental Sciences at University of Copenhagen are also involved in AnaEE Denmark activities with measurements of GHG exchange in agricultural systems. They will participate with lectures and be responsible for the field visit to the Højbakkegård site during the course.