Crop Nutrients With IOT

Soil is the Base of Agriculture

and it provides nutrients for the growth of a crop. Some of the chemical and physical properties of soil such as moisture, temperature and soil's NPK content can heavily affect the yield of a crop and these properties can be sensed by the open-source hardware which can be used in the field.

The soil monitoring with IoT uses technology which empowers the farmers and growers to maximize their yield, reduce disease and optimise resources. They can measure soil temperature, NPK, volumetric water content, photosynthetic radiation, soil water potential and soil oxygen levels. These parameters can be monitored wirelessly on a mobile phone or a PC system. The data from these are transmitted back to a central point (or cloud) for analysis, visualisation and trend analysis. The resultant data is then used for optimising the farming operations, identifying the trends and making subtle adjustments to maximize the yield of Crop and its quality. The use of IoT in agriculture is known as Smart Agriculture/Farming and IoT is also a Central component of Precision farming.

Soil Properties Measurement

IoT and Smart Agriculture Technology from Libelium can measure these properties in the soil:

Soil Moisture (up to three times depth)
Conductivity
Volumetric Water Content
Soil Water Potential

For measuring soil moisture level, we need soil moisture sensors and generally, Capacitive types of soil moisture sensors are preferred because they have the advantage that they are made of a corrosion resistant material which provides long service life. This type of sensor operates between 3.3 volt to 5.5 volt DC voltage and the output is in the form of Analog up to 3 volt maximum.

NPK Soil Sensors

The soil NPK sensor is suitable for detecting the content of Nitrogen, Phosphorus, and Potassium in the soils, helping determine the fertility of the soil. These sensors can be buried in the soil for an extended period. NPK IoT sensors use various technologies, with the most common method being TDR (Time Domain Reflectometry). This sensor supports RS485 for integration into IoT solutions, including LoRaWAN and data loggers. They do not require any chemical reaction and offer high measurement accuracy, fast response speed, and good interchangeability. The sensor can be used with any type of microcontroller and operates on 9 to 24 volts with an accuracy up to within 2%.

The Combined NPK Sensors Can Measure:

Nitrogen
Phosphorus
Potassium
pH
EC (Electrical Conductivity)
Temperature
Moisture

Nutrient management is a process of managing the amount, source, timing and method of nutrient application while minimising the loss of nutrients which could create environmental problems and it has a primary goal of optimising the productivity of a Farm. It includes developing nutrient budgets that consists of knowing the amount of nutrients that is already present in the soil and determining the amount of nutrients which is needed by the crop accounting for all the potential sources of the nutrients and then applying manures, compost, irrigation water or inorganic fertilizers for meeting the nutrient need of the crop. The management practices also use site management practices for increasing and maintaining the soil quality for reducing the potential for erosion and nutrient transportation into surface water or leaching into groundwater. The quality of soil is a very important component of nutrient management as it affects the nutrient retention and water movement through the soil.

Right amount: Proper rate of application
Right source: Proper type of application
Right placement: Using the appropriate method of application
Right timing: Proper time of application

Integrated Nutrient Management

Integrated nutrient management is the combined application of chemical fertilizers and organic manures for crop production with the main aim of maintaining soil fertility and supplying plant nutrients in adequate amounts. It is ecologically, socially, and economically viable.

Importance of Nutrient Management

Nutrient Management is important for the following reasons:

It helps in reducing contamination to waterways by plant nutrients.
It improves the fertility of the soil.
It enhances the productivity of a plant.
It reduces the cost of chemical fertilizers.
It provides balanced nutrition to crops.
It promotes carbon sequestration and prevents the deterioration of soil, water, ecology, and it also prevents the leaching of nutrients from the soil.