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滨海稻区田间道路与排灌渠道布置有两种.一是两沟夹一道(见图1).这种布置形式,排水支渠是单向控制.其优点是排水条件好,若以支渠为单位实行水旱轮作,可以防止旱田受浸润.缺点是占地多,小桥小涵多.另一种形式是两道夹一沟(见图2).这种布置形式适用于老稻区,其排水支渠为双向控制.田间干道直接修在条田的一端,排水毛渠穿过干道底部涵管与排水支渠相通.其优点是,
There are two types of coastal roads and irrigation and drainage channels in the coastal rice paddies: one is a ditch with two ditches (see Figure 1) .In this arrangement, the drainage branch is a one-way control, which has the advantage of good drainage conditions and good drainage conditions Drought and drought rotation, can prevent infiltration of dry fields. The disadvantage is that more land, small bridges and more. Another form of two folders a ditch (see Figure 2). This arrangement is suitable for the old rice area, the drainage Branch canal for the two-way control .Field road directly at the end of the field, drainage channel through the culvert at the bottom of the trunk and drainage branch canal connected .One advantage is that,