Before revision:  Using a simple individual-based model for vegetation dynamics, we show that environmental  variability --a well-recognized characteristic feature of semiarid environments-- promotes the emergence of power-law vegetation patches in a robust way (i.e. for a broad range of parameter values)  .
After revision:  Using a simple individual-based model for vegetation dynamics, we show that environmental variability --a well-recognized characteristic feature of semiarid environments-- promotes the emergence of power-law vegetation patches in a robust way (i.e. for a broad range of parameter values) the emergence of scale-free vegetation patches .