A field survey of soil pH and extractable aluminium in the Ashburton Lakes Catchment, Canterbury, New Zealand.
Soil extractable aluminium (Al) concentrations have a strong impact on the establishment, growth
and persistence of pasture legumes. A survey of 21 soil profiles in the Ashburton Lakes catchment
was conducted to determine the key factors driving extractable Al concentrations. The mean Al (0.02 M
CaCl2) concentration was 7.8 mg/kg with the highest values in the top 50 cm of the soil profile. However,
there was considerable variation among sites. Landform age, rainfall and depth were all important variables for
extractable Al (but R2 was low), while landform type was not. The highest Al concentrations in the 20 cm depth
zone were found at the wettest sites in the catchment where rainfall was ≥ 1266 mm and where pH was lowest.
Farmers in this catchment could use this knowledge to determine which areas of their farms are most susceptible to elevated Al concentrations and at what depth. This would assist in determining which areas could be targeted for development and which are unsuitable.
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
This work is licensed under a Creative Commons Attribution-Non Commercial-NoDerivatives 4.0 International License. Rights granted to the New Zealand Grassland Association through this agreement are non-exclusive. You are free to publish the work(s) elsewhere and no ownership is assumed by the NZGA when storing or curating an electronic version of the work(s). The author(s) will receive no monetary return from the Association for the use of material contained in the manuscript. If I am one of several co-authors, I hereby confirm that I am authorized by my co-authors to grant this Licence as their agent on their behalf. For the avoidance of doubt, this includes the rights to supply the article in electronic and online forms and systems.