1 23 Plant and Soil An International Journal on Plant-Soil Relationships ISSN 0032-079X Volume 360 Combined 1-2 Plant Soil (2012) 360:163-174 DOI 10.1007/s11104-012-1220-9 Litter VOCs induce changes in soil microbial biomass C and N and largely increase soil CO 2 efflux Dolores Asensio, Jorge Curiel Yuste, Stefania Mattana, Àngela Ribas, Joan Llusià & Josep Peñuelas