World Soil Day

  Soil biological diversity reflects the variability among living organisms including a myriad of organisms not visible to the naked eye, such as microorganisms (e.g., bacteria, fungi, protozoa) and meso-fauna (e.g., nematodes, acari and springtails), as well as the more familiar macro-fauna (e.g. earthworms, ants and termites). The most recommended methods for soil biodiversity include the counting and identification of macro and mesoorganisms by a trained person, following extractions in the laboratory (e.g., Berlese funnel, Baermann funnel or pitfall traps in the field). A regular genomic analysis biodiversity to be assessed more accurately at the microbial level. It is recommended to associate at least one of these methods with the respiration rate mentioned in the recommended indicators in order to better interpret the values obtained.

  Soil pH (acidity and alkalinity) gives an important indication of plant nutrient availability, and different crops thrive at different pH values. Soil pHmay change in response to management activities such as liming, fertilizeraddition, irrigation that leads to salt accumulation, and some forms of soil pollution. Soil pH may be measured in the field with simple indicators, or with standard laboratory measurements. It is relatively cheap, quick, and easy to determine. Amending a low (acidic) pH can lead to greatly improved crop yields.

  Water capacity refers to the water held in the soil between its field capacity and permanent wilting point. It represents the Ecosystem service of regulating water quality and availability in the landscape (easily available water is held between -10 and -200 kPa). This parameter can also help assess the physical condition of a soil (porosity and structure) as wateravailability is highly dependent on it.