Research On Tandem Ponds Rainwater Utilization System Apply To Mid-levels And Polder Area

With the increasing shortage of water resources, the water conflict is rising. Agriculture is one of China’s major water user, but it’s water-saving potential is also greatest. Rain as a potential water resource developing rapidly, particularly suited for those not be centralized water supply in mountain area, mid-levels, and lack of surface water and groundwater area. Through the utilization of irrigation reservoirs, ponds and other storage facilities to collect rainwater in wet season and supply water in dry period, can effectively guarantee the local agricultural irrigation demand and the sustainable development of farmland ecological environment.Pond rainwater collection and utilization system, it has the characteristics of intercept the local runoff, distributed storage water, nearby irrigation, water supply in a timely manner, slow and reduce flood peak,etc. Tandem ponds has extensive applicability in hill. Water storage irrigation can also effectively solve the run off loss in mid-levels and polder area, solve the water supply tension caused by uneven seasonal rainfall, improve the low efficiency of water resource utilization and solve the drainage pressure of the long-standing. Meanwhile, it is useful for Intercepting the nitrogen, phosphorus and potassium in the water, which protecting the soil fertility and relieving ecological pollution in downstream river channel.Mid-levels and polder area has the both characteristics of hill and polder. According to the characteristics of mid-levels and polder area, the paper carry out the research about how tandem ponds apply to collect rainwater in mid-levels and polder area. The tandem ponds rainwater collection and utilization system model includes rainwater collection system, rainwater storage system and rainwater utilization system. On the premise of guaranteeing regional ecological environment of water needs and based on principles of "more storage more use and less drainage ", the paper build the tandem ponds rainwater collection and utilization system model which apply to mid-levels and polder area. On the basis of analyzing runoff and the water demand of agricultural, the model can be used to optimize the volume of pond and the planting proportion in different irrigation design reliability. The paper take mid-levels and polder area beside the Hefeng Town Lishui District ShiJiu lake as study object and combined with the local agricultural production habit, then analyzes the water supply and demand situation in the study area with different irrigation design reliability, different ponds volume combination and different planting proportion, the result provide the reference for local agricultural infrastructure construction. In view of the Water distribution in study area, the paper optimize the best ponds volume combination when irrigation design reliability is 50%,75% or 95%, which can provide the reference for the local water supply project construction. Finally, combined with the local agricultural production habit, the paper optimize the best planting proportion when irrigation design reliability is 50%,75% or 95%, which can provide advice for local agricultural production arrangement.