*Reducing the Effects of Drought and Degradation of Agricultural Soils, in the Context… DOI: http://dx.doi.org/10.5772/intechopen.104446*

Refractometer measure Brix index values for liquids. Brix values indicate the total soluble solids. The refractometer is widely used in measuring the quality of the grapefruits and the time to harvest. The refractometer can be used to evaluate the overall assessment of plant health. Healthy plants with a minimum 12 Brix readings are resistant to diseases and insect attacks.

Soil pH-meter is used to measure the acidity or alkalinity of soil. The values give information about the balance of the nutrients found in the soil. However, can be also used as a pH meter for liquids, and determine pH when adding 5 parts distilled water on 1 part of the soil.

EC (electrical conductivity) meter is used especially to estimate salinity levels. A high level of salinity reduces the plant's ability to take up water. For assessment is being used 5 parts distilled water and 1 part soil to determine the values of salinity in mSiemens/cm. In clay soils, values are between 0.2 and 1.0 mS/cm, but different plants tolerate different values.
