OC-13.3: Change in soil moisture content

Owned by Enrico Bonaiuti
May 05, 2020
2 min read

Definition: This indicator will focus on the amount of water present in the soil.

Unit of Measure: Percentage

Disaggregated by: Agro-ecological zone, geographical area (national, sub-national)

Method of Calculation:
Step 1: Follow the instructions in this manual to measure soil moisture content
Step 2: Compute the change in soil moisture as per the equation below
Change in soil Moisture=Moisturetn-MoisturetoMoistureto×100
Moistureto denotes soil moisture level in the first reporting period (e.g baseline) and Moisturetn denotes soil macronutrient level in subsequent reporting periods (e.g mid-term, end-term).

Data sources: Farmers' fields/plots

Data collection method: Soil sampling.
Additional remark on soil sampling: A soil sample should be composed of several sub-samples representing a seemingly uniform area or field with similar cropping and management history. It is recommended that eight sub-samples are taken per hectare (ha) in a diagonal pattern for obtaining one composite sample. Soil sampling Should be done at depths of about 20-cm and 60-100 cm. See detailed information in the Manual.

Data collection and reporting responsibility: Program leader, project leader, project M&E focal point person

Data Collection and Reporting Frequency: Annual, bi-annual, baseline, mid-term, end-term.
Additional remarks on soil sampling:

  • Soil samples can be taken any time that soil conditions permit, but sampling directly after fertilization or amendment application should be avoided.

  • Samples taken during the crop growth period will help in knowing the nutrient status of the soil in which plants are actively taking up nutrients.
    It is important to sample at similar times year after year for comparing analysis at regular time intervals.

Evidence required:
For internal evaluation or research studies: Study protocol, data collection tools, dataset, report, laboratory analysis records
For external evaluation or research studies: Request for proposals (RFP) document, inception report, final report, dataset

Rationale: Water is the most limiting factor in the arid to semi-arid areas. Soil moisture influences crop growth not only by affecting nutrient availability, but also nutrient transformations and soil biological behavior. Tracking changes in soil moisture levels through this indicator is of major significance.