Evidence of shift in C4 species range in central Argentina during the late Holocene.

SILVA L.C.R., GIORGIS M. A., MADHUR A., ENRICO L., PÉREZ-HARGUINDEGUY N., FALCZUK V. TIESZEN L. & CABIDO M.

PLANT AND SOIL

SPRINGER

Año: 2011

0032-079X

Aim Millennial-scale biogeographic changes are well understood in many parts of the world, but little is known about long-term vegetation dynamics in subtropical regions. Here we investigate shifts in C3/C4 plant abundance occurred in central Argentina during the past few millennia Methods We determined present day soil organic matter δ13C signatures of grasslands, shrublands and woodlands, containing different mixtures of C3 and C4 plants. We measured past changes in the relative cover of C3/C4 plants by comparing δ13C values in soil profiles with present day δ13C signatures. We analyzed 14C activity in soil depths that showed major changes in vegetation. Results Present day relative cover of C3/C4 plants determines whole ecosystem δ13C signatures integrated as litter and superficial soil organic matter (R2= 0.78; p