Soil pH
Benchmark Value
Scoring Curve
This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context. The scoring engine uses 10 benchmarks together — the OptimalRange form drives the primary score, while 9 guard(s) constrain the result.
Evidence & Context
Considering these factors, a soil pH(CaCl₂) below 4.7 can be identified as a critical lower threshold.
Soil pH measured in 0.01M calcium chloride solution (pH(CaCl₂)) indicating the acidity level below which ecological and agricultural functions are impaired.
This benchmark marks the critical lower soil pH threshold below which aluminium and manganese toxicity risks increase and microbial health is compromised.
Based on evidence from native ecosystem studies and agricultural guidelines indicating toxicity and microbial activity decline below this pH.
Sources (2)
McIntyre, S., Stol, J., Harvey, J., Nicholls, A.O., Campbell, M., Reid, A., Manning, A.D. & Lindenmayer, D. (2010). Biomass and floristic patterns in the ground layer vegetation of box-gum grassy eucalypt woodland in Goorooyarroo and Mulligans Flat Nature Reserves, Australian Capital Territory. Cunninghamia 11(3): 319–357.
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Grains Research and Development Corporation (GRDC). (2016). GrowNote Wheat South 05 Nutrition.
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