Figure 1

Schematic map showing the location of the ETV and GUN study sites in the Haguenau forest (France), illustrations of the sampling designs for longitudinal and depth gradients and pictures (credit P. Faure) of the ponds created by oil seeps.

Schematic map showing the location of the ETV and GUN study sites in the Haguenau forest (France), illustrations of the sampling designs for longitudinal and depth gradients and pictures (credit P. Faure) of the ponds created by oil seeps.