(How) does soil fauna survive flooding?

Background

Climate change is causing more intense rains and, as a consequence, flooding. Extensive flooding, for instance of river floodplains leads to (sub)lethal conditions for soil fauna. Soil organisms can cope with sub optimal environmental conditions in two ways: tolerance or avoidance. Species that tolerate flooding stay in the soil, conserving oxygen and relying on the little oxygen that may be left or even life in so-called plastrons. Plastrons are air bubbles in soil pores or a thin layer of air around an animals body that act as a physical long. Other species make use of avoidance strategies, such as migrating via the water surface to higher drier grounds and recolonize low elevation areas when the water subsides. It is well established that soil fauna is essential for nutrient cycling in ecosystems. Therefore, it is important to know how soil fauna communities react to flooding.

In this project you will experiment with a method to distinguish between the different strategies of soil fauna to cope with flooding. You will test which species tolerate flooding, which species avoid it and which species perish under flooded conditions. River floodplains are an ideal environment for experiments with flooding, because of their elevation gradient which determines flooding frequency and duration. Also they are inhabited by fauna that probably have different strategies to cope with flooding. In river floodplains, you will collect soil fauna before and after experimental inundation, both in the flooded soil and at just above the water level, where the avoiding species may have fled to

The aim of this internship is to assess what strategies soil fauna use to survive flooding and how the applied strategies are related to species traits.

Project goals

  • Carry out experimental inundation in river floodplains and assess the effect on springtails
  • Analyze differences in flooding survival strategies and relating these differences to species traits.

Student responsibilities

  • Learn appropriate techniques to collect and identify springtail species.
  • Set up and carry out experimental flooding in the field.
  • Identify and count extracted springtail species.
  • Extract trait information from a database.
  • Perform statistical analysis to find differences between samplings before and after inundation.

Location and Timeframe

  • Field work will be conducted at selected locations near Dutch rivers.
  • Laboratory work will be conducted at the VU.

Supervision and information

Dr. Matty Berg (Department of Ecological Science / section Animal Ecology)
E-mail:  m.p.berg@vu.nl
M: 06-12530372

Drs. Anne Krediet (Department of Ecological Science / section Animal Ecology)
E-mail: a.f.krediet@vu.nl
M: 06-26693163