A mechanistic-ecophysiological study of synergistic interactions between antrhopogenic and natural stressors: an integrated approach using oxidative stress and stoichiometry.

The goal of the experiment is to mechanistic-physiologically study synergisms using a multi-stressor multi-trait approach with 8 combinations of two anthropogenic stressors (global warming and the pesticide chlorpyrifos) and the natural stressor predation risk using damselfly larvae as study species. To simulate global warming a temperature increase of 4°C is used. To get insight in the effects on oxidative stress, both ROS (superoxide anion, hydrogen peroxide), the most important anti-oxidant enzymes in insects (SOD, CAT, GST) as oxidative damage to lipids, proteins and DNA will be quantified. Additionally the expression levels of the stress protein Hsp70, a general defence mechanism, will be measured. To integrate the effects on the C:N: P ratio, (i) these elements will be quantified, (ii) the body composition in terms of proteins, lipids and carbohydrates will be studied and (iii) an element-budget will be obtained by also measuring the C:N:P composition of the ingested food and the excreta and by quantifying the metabolic rate, both on the organismal level, via respiration, as on the cellular level as the activity of the electron transport system.

Keywords:Synergism, Predation risk, Pesticide, Oxidative stress, Global warming, Damselfly, C:N:P ratio

Disciplines:Ecology, Environmental science and management, Other environmental sciences