“三合一”水平梯田,是1955年冬莒南县厉家寨村在“二合一”梯田的基础上,加以深翻整平田面,创造的一种梯田形式.厉家寨村原先土地支离破碎.他们把1000多块零碎坡地,整成7O多块计1520亩的大块“三合一”水平梯田,由于保住水土肥,因而单位面积产量大大提高,1956年粮食平均亩产276.4公斤,比1949年翻了一番半,1957年毛主席对厉家寨科学 The “three-in-one” horizontal terrace is a form of terraced fields that was created on the basis of the “two-in-one” terraced fields in Lijiazhai Village, Dongtao County, in 1955. The original terraced fields of Lijiazhai Village Fragmented.They put more than 1,000 piecemeal sloping fields into 7O blocks of 1520 acres of large “three in one” terraced fields, due to keep water and fertilizer, which greatly increased yield per unit area, 1956 grain average yield 276.4 kilograms, More than doubled that of 1949, Chairman Mao Zili made his scientific study in 1957