Overview
EN ISO 23753-2:2019/A1:2020 is an internationally recognized European standard that specifies a method for determining dehydrogenase activity in soils. This technique utilizes iodotetrazolium chloride (INT) to accurately assess soil biological quality through enzymatic activity measurement. Developed by ISO Technical Committee 190 and endorsed by the European Committee for Standardization (CEN), this amendment updates the original 2019 version, providing refined procedural guidelines for enhanced reliability.
The standard is essential for soil scientists, environmental researchers, and agricultural professionals who require precise soil quality assessment tools. Dehydrogenases are important soil enzymes involved in microbial oxidative activities, serving as indicators of overall soil health and microbial function.
Key Topics
- Dehydrogenase Activity: Measurement of this enzyme's activity reflects microbial metabolic status and soil biological activity.
- Use of Iodotetrazolium Chloride (INT): This chemical acts as a substrate to produce a quantifiable colored compound, iodonitrotetrazolium formazan (INTF), allowing spectrophotometric analysis.
- Standard Curve and Calculation: The amended method emphasizes constructing a linear standard curve correlating INTF concentration (nmol/ml) to its absorbance, improving accuracy.
- Formula for Enzymatic Activity:
The dehydrogenases activity (A) is calculated considering:
- INTF concentrations in sample and control tubes
- Reaction volume and time
- Soil mass and dry matter content (%DM)
This quantification is expressed in milliunits per gram of dry soil sample (mU/g), facilitating comparability between samples.
- Compliance and Standardization: This amendment requires member states of CEN to adopt it by May 2021, ensuring harmonized soil quality evaluation across Europe.
Applications
- Soil Quality Monitoring: Essential for tracking soil biological health in agriculture, forestry, and natural ecosystems.
- Environmental Impact Assessments: Evaluates effects of pollutants or land use changes on soil microbial activity.
- Land Remediation Projects: Assists in monitoring recovery and restoration of microbial function in contaminated or disturbed soils.
- Research and Development: Provides a standardized laboratory method for scientific studies regarding soil microbiology and enzymatic processes.
- Agricultural Management: Supports decision-making to optimize soil fertility and microbial balance for crop production.
Related Standards
- ISO 23753 Series: This document is part 2 of the overall ISO 23753 series focused on soil dehydrogenase activity determination methods.
- ISO 11465: Specifies soil dry matter content measurement, critical for calculating enzyme activity accurately.
- ISO/TC 190 Soil Quality Standards: Other related standards cover physical, chemical, and biological soil properties to complement enzyme activity evaluations.
- CEN/TC 444 Environmental Characterization: Provides standards for testing and characterizing solid environmental matrices, reinforcing soil quality assessments.
Keywords: EN ISO 23753-2, soil quality, dehydrogenase activity, iodotetrazolium chloride, INT method, soil enzyme assay, soil microbial activity, environmental soil testing, standardized soil analysis, biological soil properties, soil health indicator, CEN soil standard.