sch.3-sec.15Meaning of soil physico-chemical limitation

### sch.3-sec.15 Meaning of soil physico-chemical limitation A soil physico-chemical limitation , for soil, means it has— for any soil in the Western Cropping zone or Eastern Darling Downs zone—a chloride content of more than 800mg/kg; and for any soil in the Coastal Queensland zone, Granite Belt zone or Wet Tropics zone—an electrical conductivity of more than 0.56dS/m; and for any soil in any zone—a soil pH of 5.0 or less; and for rigid soils in any zone— a soil pH of more than 8.9; or an exchangeable sodium percentage of more than 15; or a calcium to magnesium ratio of 0.1 or less. The exchangeable sodium percentage is the percentage of the total cation exchange capacity ( CEC ) due to exchangeable sodium, measured using— generally—the most appropriate method described in table 15.2 of soil chemical methods; or for strongly acid soils—method 15J1 in soil chemical methods (known as ‘effective CEC’ or ‘ECEC’). However, the exchangeable sodium percentage must not be used if— the CEC or ECEC is less than 3cmol c /kg; or the soil texture is sandy loam or lighter as defined under the field handbook. The calcium to magnesium ratio is the ratio of exchangeable calcium to exchangeable magnesium worked out using a relevant method under soil chemical methods. (sch.3-sec.15-ssec.1) A soil physico-chemical limitation , for soil, means it has— for any soil in the Western Cropping zone or Eastern Darling Downs zone—a chloride content of more than 800mg/kg; and for any soil in the Coastal Queensland zone, Granite Belt zone or Wet Tropics zone—an electrical conductivity of more than 0.56dS/m; and for any soil in any zone—a soil pH of 5.0 or less; and for rigid soils in any zone— a soil pH of more than 8.9; or an exchangeable sodium percentage of more than 15; or a calcium to magnesium ratio of 0.1 or less. (sch.3-sec.15-ssec.2) The exchangeable sodium percentage is the percentage of the total cation exchange capacity ( CEC ) due to exchangeable sodium, measured using— generally—the most appropriate method described in table 15.2 of soil chemical methods; or for strongly acid soils—method 15J1 in soil chemical methods (known as ‘effective CEC’ or ‘ECEC’). (sch.3-sec.15-ssec.3) However, the exchangeable sodium percentage must not be used if— the CEC or ECEC is less than 3cmol c /kg; or the soil texture is sandy loam or lighter as defined under the field handbook. (sch.3-sec.15-ssec.4) The calcium to magnesium ratio is the ratio of exchangeable calcium to exchangeable magnesium worked out using a relevant method under soil chemical methods. - (a) for any soil in the Western Cropping zone or Eastern Darling Downs zone—a chloride content of more than 800mg/kg; and - (b) for any soil in the Coastal Queensland zone, Granite Belt zone or Wet Tropics zone—an electrical conductivity of more than 0.56dS/m; and - (c) for any soil in any zone—a soil pH of 5.0 or less; and - (d) for rigid soils in any zone— (i) a soil pH of more than 8.9; or (ii) an exchangeable sodium percentage of more than 15; or (iii) a calcium to magnesium ratio of 0.1 or less. - (i) a soil pH of more than 8.9; or - (ii) an exchangeable sodium percentage of more than 15; or - (iii) a calcium to magnesium ratio of 0.1 or less. - (i) a soil pH of more than 8.9; or - (ii) an exchangeable sodium percentage of more than 15; or - (iii) a calcium to magnesium ratio of 0.1 or less. - (a) generally—the most appropriate method described in table 15.2 of soil chemical methods; or - (b) for strongly acid soils—method 15J1 in soil chemical methods (known as ‘effective CEC’ or ‘ECEC’). - (a) the CEC or ECEC is less than 3cmol c /kg; or - (b) the soil texture is sandy loam or lighter as defined under the field handbook.