Nutrient limitation along the Jurien Bay dune chronosequence: response to Uren & Parsons ()

Abstract

* Uren & Parsons () criticize our nutrient addition experiment and question the integrity of the Jurien Bay dune chronosequence. Their primary criticisms relate to (i) inconsistencies in parent material along the chronosequence and (ii) the lack of consideration of micronutrients in our glasshouse experiment. * We reaffirm that the Quindalup Spearwood succession is a consistent Holocene Middle (possibly Early) Pleistocene soil chronosequence in which parent material, topography, and present-day climate and vegetation type (i.e. Mediterranean shrubland) are held relatively constant. The older (Early Pleistocene Late Pliocene) Bassendean Sand probably contained less carbonate initially, but nevertheless represents the endpoint of an exceptionally strong gradient in soil nutrient availability. * The claim that we did not consider the potential importance of micronutrients is unfounded. We included a micronutrient treatment in our experiment and discussed the importance of micronutrient availability in young calcareous substrates. * Synthesis. We restate that our experimental results support predictions about changes in nutrient limitation during long-term pedogenesis, and affirm that the Jurien Bay chronosequence is a valuable model system for addressing ecological questions related to pedogenesis, plant diversity and plant soil interactions.