fluvial plain meaning in Chinese

冲积平原
河成平原
河积平原

The phreatic groundwater in the diluvial fan in front of the helan mountain is mainly recharged by precipitation and the lateral flow from the helan mountain ; the phreatic groundwater both in the diluvial fan of the qingtongxia gorge and in the fluvial plain is mainly recharged by the influent seepage of irrigation water from the yellow river
贺兰山洪积扇单一潜水主要接受山区侧向径流及大气降水补给；青铜峡洪积扇单一潜水及冲湖积平原上覆潜水，主要接受黄河灌溉水的入渗补给。