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这里所说的淹没地区系指我国北方常遭淹没的大面积耕地地区,或局部较低窪的地区(俗称活窪)。此种淹没区,地势平坦,河道宽浅,干旱季节河中无水或水很少,在雨量不多的年份,雨季里河水水面并不很宽;但在多雨年份,当连雨或暴雨之后,河水漫溢两岸,广大耕地遭受淹没。因地势平坦主河槽水流流速不大,一般被淹耕地中水流流速很小,淹水深度一般不深,不过垂直于水流方向的水面宽度很大,有时达数公里甚至十多公里。在这种地区筑路,若按一般规定处理,时常导致淹没区的扩大和淹没时间的延长,从而加重农作物受
Submerged here refers to a large area of cultivated land, often submerged in the northern part of our country, or a part of the lower-lying area (commonly known as live-wa). Such submerged area, flat terrain, shallow river, dry season, little or no water in the river, rainfall is not much in the years, the surface water is not very wide during the rainy season; but in the rainy years, when the rain or even after the rain, The rivers overflowed the two sides of the strait and vast arable land was submerged. Because of the flat terrain, the flow velocity of the main channel is not large. Generally, the flow rate of water in submerged arable land is very small, and the depth of flooding is generally not deep. However, the water surface perpendicular to the flow direction is very wide, sometimes up to several kilometers or even over 10 kilometers. Road construction in such areas, if handled in accordance with the general provisions, often leads to the expansion of inundation areas and prolonged submergence, which aggravates the crops