Due to its diversity and different geographical conditions, Southeast Asia uses many different irrigation methods to suit the needs of different regions and crops. Here are some common irrigation methods in Southeast Asia:

1. Flood irrigation: Flood irrigation is one of the oldest and most common irrigation methods in Southeast Asia. It uses the flow of water from rivers, lakes and man-made channels to channel water into agricultural fields. This method is usually used during the rainy season when the water flow is abundant, and it is suitable for crops such as rice.

2. Ditch irrigation: Ditch irrigation is a way of directing water to farmland by digging and constructing ditches. This method can control the water flow and is suitable for a variety of crops.

3. Drip irrigation: In some Southeast Asian regions, drip irrigation technology has gradually been applied. Drip irrigation reduces water wastage by releasing water droplets tick-tock at plant roots, making it suitable for water-saving environments, especially in areas with limited water resources.

4. Sprinkler irrigation: Sprinkler irrigation sprays water in the air by using sprinklers, similar to natural rainfall, and is suitable for many crops, especially in dry seasons.

5. Underground drip irrigation: Underground drip irrigation is the supply of water to the roots of plants through pipes and drip irrigation devices buried in the ground. This method can reduce water evaporation and waste, which is suitable for crops that require fine water control.

6. Dip irrigation: Dip irrigation is to soak the entire farmland surface in water to make the soil fully absorb water. This method is commonly used in rice cultivation.

It is important to note that irrigation methods may vary from country to country depending on land characteristics, climatic conditions, water availability and crop type.