Authorship statement:
TMB designed the field experiment. RH, FZ, MH, TMB, executed the first
phase of the field experiment. All authors contributed to maintenance of
the second phase of the experiment. RH, EH, JDL, FZ, KS, MH, RJ, TMB
collected field data. EH, RH and JDL analyzed soil microbial and
vegetation data. RH led the writing of the manuscript, in close
collaboration with EH, JDL and TMB. All co-authors contributed
critically to the manuscript and approved the final version for
publication.