Do variations on a model of landscape function assist in interpreting the growth response of vegetation to rainfall in arid environments?

Across nearly 100 sampling locations widely distributed within the arid shrubland of Western Australia, we demonstrated a general relationship between landscape function, primary productivity and rainfall-use efficiency. Sampling locations included landscapes that had been severely ‘degraded’ by more than 100 years of grazing, mainly by sheep. There was generally less phytomass and poorer rainfall-use efficiency on dysfunctional or degraded landscapes than on functional or non-degraded landscapes. Relationships were stronger at broader spatial scales of patch-mosaics than at the scale of individual patches and are likely to be more readily interpreted over decadal rather than yearly time-scales. A-priori assessment of landscape ‘resilience’ provided few insights into the capacity of landscapes to respond to rainfall. Contrary to expectations, herb mass increased on both resilient and non-resilient landscapes as proportional areas occupied by vegetated patches declined