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喜兴市新丰公社林金大队地势平坦低洼,境内河网密布,地下水位埋置很浅,一般为0.2—0.4米,农田土壤以青紫粘土为主,粘性大,透水性差。遇到多雨年份,地下水位抬高、渍害严重,造成烂冬烂春,尤其是占全大队水田总面积百分之三十以上的六百多亩田块,灌得进排不出,地下水位控不住,经常积水,土烂泥粘,当地农民称它为“烂水田”。由于土烂湿重,春粮生产比一般正常田块减产二、三成,严重的达四、五成。一九七一年至一九八○年的十年间春粮生产有五年增产,五年减产,波动大,不稳定。林金大队总结春粮生产上不去的主要原因是:耕作层下面有20—30厘米厚的犁底层,土质粘密,阻碍渗透,地下水位抬高,致使作物根系不能深扎,形成渍害。因此,这个大队自一九七七年起,把原来30厘米深的浅鼠道加深为60厘米深的深鼠道,并与灰土暗沟、启闭控制阀门配套,在出面以下布置排水通道,给已入渗的两水和正在上升的地下水以出路,达到缩短土壤过湿状态持续
Xinshin Xinfeng commune forest brigade flat low-lying, dense river network, the groundwater level is very shallow, generally 0.2-0.4 meters, farmland soil to purple clay, sticky, poor water permeability. In rainy years, groundwater levels are elevated and waterlogging is serious, causing rotten spring with rotten winter, especially over 600 acres of fields that occupy more than 30% of the total paddy fields of the entire brigade. Can not control bits, often water, soil sticky mud, local farmers call it “rotten paddy field.” Due to the rotten soil, the output of spring grains is reduced by 20% to 30% compared with the average normal plots, reaching 40% to 50%. Spring grain production has been increasing for five years in a decade from 1981 to 1980, with a yield reduction and volatility in five years, fluctuating and unstable. The main reason why the forest brigade summed up the failure of spring grain production is that there is a 20-30 cm thick plow bottom under the tillage layer, soil is so thick that it hinders infiltration and elevation of underground water, resulting in that the crop roots can not be dug deep and form stains . Therefore, starting from 1977, this brigade has deepened the shallow centimeter of 30 centimeters deep to a depth of 60 centimeters and connected it with a ditches and ditches of open-close control valves. Arranged drainage channels below Infiltration of two water and rising groundwater in order to shorten the soil over-wet conditions continue