Decline of herbivorous insects uncovered by eDNA and plant chemical composition
Insects are essential providers of ecosystem services such as pollination and nutrient recycling. There are increasing worries that insect populations are crashing on a global scale.
Insects face numerous threats from habitat degradation, climate change, pesticides and pollution. We propose to collect leaves from birch trees along gradients in latitude, land use and vegetation composition spanning the whole of Sweden. The leaves would then be analysed for their content in nutrients, secondary compounds, volatile organic compounds, pesticides and heavy metals. In parallel, the diversity of insects using the leaves would be estimated using an eDNA metabarcoding approach that we develop expressly for this purpose.