Explain two methods of irrigation scheduling?

1. Soil moisture-based scheduling: This method involves monitoring the soil moisture levels in the root zone of the plants to determine when irrigation is needed. This can be done using soil moisture sensors or by manually checking the soil moisture levels. By maintaining the soil moisture at optimal levels, plants receive the right amount of water they need for healthy growth and development. This method helps prevent overwatering or underwatering, which can lead to water wastage or plant stress.

2. Evapotranspiration-based scheduling: Evapotranspiration (ET) is the combined process of water evaporation from the soil surface and transpiration from plant leaves. By calculating the rate of ET, irrigation scheduling can be adjusted to match the water loss from the soil and plants. This method takes into account environmental factors such as temperature, humidity, wind speed, and solar radiation to estimate the water requirements of the plants. By using ET data, farmers can determine when and how much water to apply to their crops to maintain optimal soil moisture levels.