Paper isn't on scihub, but I wonder if the authors paid any attention to electrons vs protons in the "current": In most biological systems electric charge is a

Paper isn't on scihub, but I wonder if the authors paid any attention to electrons vs protons in the "current": In most biological systems electric charge is a property of (mostly positive, metal) ion concentration gradients which are managed quite selectively (e.g. a cell might have high interior/low exterior potassium and also high exterior/low interior sodium) And an electric current through the dirt near roots is a flow of cations near the roots So I'm wondering if they controlled for mass transfer - Maybe some of it is just making mass transfer of something in/out of the root vicinity less of a rate limiting step