Production function 1. 2.
3.
4.
5. Increase production per unit area
Increase cultivation area
Avoid damages of continuous cropping
Improve field soil by settling silts in the irrigation water Maintain soil productivity
Ecological function 1.
2.
3. 4.
5.
7.
8.
9.
10.
11 Replenish groundwater resources
Stabilize river flow
Flood control by reducing peak flow (paddy fields as reservoirs)
Mitigate land subsidence
Maintain clean water quality; purify air
Adjust micro-climate Prevent soil erosion
Desalt
Conserve wetland, and provide sanctuary for water birds . Water resources cycles
Living function 1. Improve living environment and sanitary of farms
2. Provide miscellaneous water and fire hydrant in farms
3. Aid domestic water supply during water shortage
4. Promote communication and cooperation among villages via management organization systems
5. Provide comfortable living environment and fair scenery
6. Provide leisure of cultural education
7. Stabilize people’s living