Biomass partitioning of plants under soil pollution stress.

Polluted sites are ubiquitous worldwide but how plant partition their biomass between different organs in this context is unclear. Here, we identified three possible drivers of biomass partitioning in our controlled study along pollution gradients: plant size reduction (pollution effect) combined with allometric scaling between organs; early deficit in root surfaces (pollution effect) inducing a decreased water uptake; increased biomass allocation to roots to compensate for lower soil resource acquisition consistent with the optimal partitioning theory (plant response). A complementary meta-analysis showed variation in biomass partitioning across published studies, with grass and woody species having distinct modifications of their root: shoot ratio.

Aided-phytostabilization of steel slag dumps: The key-role of pH adjustment in decreasing chromium toxicity and improving manganese, phosphorus and zinc phytoavailability.

Because of their high content in toxic metals, steel slag dumps are potential threats for the environment and public health. Among management methods that could mitigate their hazard, aided-phytostabilization is a relevant, though challenging, option. Indeed, steel slags are very unfavorable for plant growth, due to metal toxicity and very alkaline pH (>10).