Читать книгу The Digital Agricultural Revolution - Группа авторов - Страница 41

Sensors collect data from crops, livestock, soil, and the atmosphere. The sensor data are supplied to a cloud-based IoT platform with preprogrammed decision rules and models that determine the status of the studied object and highlight any flaw or requirement. Following the discovery of difficulties, the IoT platform’s user and/or ML-driven components assess whether and which location-specific treatments are required. Various sensors used for smart farming are shown in Figure 1.8.

Electromagnetic sensors detect the ability of soil particles to conduct or acquire electrical charge using electric circuits. The electrical conductivity of the soil is immediately recorded in a logger after it becomes a member of the electromagnetic circuit. To measure electrical conductivity, contact EC sensors use electrodes and make contact with the soil. The data, as well as the position information, are stored in a data logger. Contact EC sensors are highly common in precision agriculture because of their large area coverage and less prone to outside interference.

Figure 1.8 Various sensors for smart farming.

Optoelectronic devices allow for such interaction. In general, optoelectronic sensors use the properties of various materials to create a spectral signature. A common type of sensor in this category is the soil organic matter (SOM) sensor that uses the optical method.

An ion-selective electrode is used for some measurements. The activity of certain ions is detected by these electrodes. The mechanical resistance of the soil is measured by mechanical sensors. Airflow sensors are used to determine the air permeability of the soil. The sensor detects the pressure required to compress a specific volume of air into the soil at a specific depth.

Acoustic sensors: The change in noise level caused by the tool’s interaction with the soil particles is used to evaluate soil texture. Soil pH sensors detect acidity and alkalinity in the soil, which can lead to fertility issues, stunted growth, oddly colored leaves, and poor plant health. Ammonium sensors detect exact ammonia and nitrogen concentration and nitrate sensors are devices that detect the presence of nitrate in the soil or water.

Potassium sensors: These devices monitor potassium levels in the soil to better understand the relationship between free potassium in soil nutrients reserves, soil texture, and root growth, which could lead to more efficient fertilizer use. Soil-water sensors are useful for detecting local energy and water balances, delivery of applied chemicals to plants and groundwater, irrigation management, and precision farming.