Impacts of MEtal and CLImate change on NUTrient cycling in the rhizosphere of phytoremediating plants

At a global level, the management of contaminated sites (including soils) is gaining relevance in environmental and political agendas. Metal contamination in soils poses an important risk to environmental and human health.

Even though research on metal contamination has received plenty of attention over the last decade, major knowledge gaps exist about the impacts of metals on nutrient cycling processes.

Even less is known about the coupled effects of metal contamination and climate change conditions on phytoremediation efficacy and associated nutrient dynamics in the soil.

The NutCliMe project (Impacts of Metal and Climate change on Nutrient cycling in the rhizosphere of phytoremediating plants) aims to disentangle the interplay of nutrient dynamics and soil microorganisms in the rhizosphere of metal-hyperaccumulating plants used for metal extraction under today and future climate conditions.

This will be accomplished by studying a model plant for metal-hyperaccumulation, Arabidopsis halleri.

Plants will grow in rhizoboxes and in fully controlled greenhouse chambers with temperature and CO2 concentration based on todays and the IPCC Rcp 8.5 scenario climatic conditions.

The combination of isotope pool dilution assays with transcriptomics will allow to assess how metal contamination and climate change affect key process rates in nutrient cycling and its linkage with the active microbial community composition in the rhizosphere.

The integration of zymography, pore water sampling, -XRF elemental mapping, and gene amplicon sequencing analysis will elucidate the interplay of roots and soil microorganisms in the spatial distribution of nutrient cycling enzymes, and the availability of metals and nutrients.

The outcomes of this project are also expected to provide valuable information about how nutrient fluxes are primarily affected and are limiting plant growth and metal accumulation, which may be helpful to improve phytoremediation and phytomining.