农谚说:“换茬如换油”,“茬口倒得顺,粮食打满囤”。通过换茬,可以使根系深浅不同,吸收养分种类不同的作物互相搭配,达到全面利用土壤养分,提高作物产量,用地与养地相结合的目的。其具体的换茬原则是: 一、肥茬与瘦茬轮作。各种豆类和绿肥作物,即能固定空气中的氮素,又能吸收利用土 Agricultural proverb said: “Change the crop, such as oil change,” “stubble down Shun, food hoarding.” Through the replacement of stubble, you can make the roots of different shades, absorb nutrients with different types of crops with each other, to achieve full use of soil nutrients and improve crop yields, land and the purpose of the combination of land. The specific principle of stubble is: First, stubble and stubble crop rotation. A variety of beans and green manure crops, that is, nitrogen in the air can be fixed, but also to absorb the use of soil