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镇江丘陵地区地处江南,小麦生长季节往往雨水较多,麦田地下水位较高,引起秋播期烂耕烂种,苗期僵苗不发,后期早衰枯熟等湿害现象,对小麦高产稳产的威胁很大。丘陵麦田湿害的特点(一)地面径流较大:丘陵山区地势起伏,田块之间的高低差别较大,多在1尺左右,有的挂坎高达3尺以上。雨后丘陵麦田常会产生较大的地面径流,顺地势流动往往冲漫麦田,造成严重湿害。(二)有一股地下渗流:由于高程差,雨水渗入麦田,顺地势由高向低流动。1.地下渗流由自上而下纵向渗流与向四周水平方向横向渗流合成,两股渗流速度的快慢决定地下渗流的流动方向。
Zhenjiang hilly area is located in the south of the Yangtze River, wheat growing season are often more rainwater, wheat fields higher groundwater levels, causing rotten cultivated rotten seeding autumn, seedling stage rigid seedlings do not send late maturing premature blight and other wet damage, high and stable yield of wheat The threat is great. Characteristics of wet injury in hilly wheat fields (I) Larger runoff: The hilly and mountainous terrain is undulating, and the difference between the fields is relatively large, mostly about 1 foot, with some hanging basins up to 3 feet or more. After the rain, the hilly wheat fields often produce large surface runoff, which tends to rush into the mangroves and cause severe wet damage. (B) there is a subterranean seepage flow: due to poor elevation, rainwater infiltration wheat fields, along the trend from high to low flow. 1. Underground seepage flow from the top-down seepage and horizontal seepage to the surrounding horizontal synthesis, the two seepage flow rate determines the flow direction of underground seepage flow.