Stress responses investigated; application of zinc and heat to Terrestrial Model Ecosystems from heavy metal polluted grassland.

This study tested the hypothesis that soils with a deprived biodiversity due to metal pollution are less stable than non-polluted soils, containing a more diverse community. For this, soils were sampled from specific grasslands in the Netherlands that contain elevated heavy metal concentrations (Cu, Pb and Zn). Soils that showed the largest differences in metal concentrations were incubated in the laboratory using Terrestrial Model Ecosystems (TMEs).

Assessment of structure and function in metal polluted grasslands using Terrestrial Model Ecosystems.

Ecosystem effects of metal pollution in field situations are hard to predict, since metals occur often in mixtures and links between structural (organisms) and functional endpoints (ecosystem processes) are not always that clear. In grasslands, both structure and functioning was suspected to be affected by a mixture of copper, lead, and zinc. Therefore, the structural and functional variables were studied simultaneously using Terrestrial Model Ecosystems (TMEs).

Functional recovery of biofilm bacterial communities after copper exposure.

Potential of bacterial communities in biofilms to recover after copper exposure was investigated. Biofilms grown outdoor in shallow water on glass dishes were exposed in the laboratory to 0.6, 2.

Effects of copper and temperature on aquatic bacterial communities.

The present study aimed to characterise effects of copper and temperature on bacterial communities in photosynthetic biofilms using a suit of supplementary methods: pollution-induced community tolerance (PICT), DNA profiles with denaturing gradient gel electrophoresis (DGGE) and physiological profiles with community-level physiological profiling (CLPP). Biofilms of algae and bacteria were grown in a ditch of a Dutch polder and exposed in the laboratory to copper (3 microM and a reference) at three different temperatures (10, 14 and 20 degrees C). Bacterial communities sampled from the field showed heterogeneity in their physiological profiles, however the heterogeneity decreased during laboratory incubation.