Water and nitrogen are the most important two factors for crop production in agriculturepractice. Continuously, people paid close attention to the relationship between two factors.
No-till agriculture, an agronomic practice in which farmers do not plough up the land but leave part of the previous year's crop on it, also preserves water.
免耕农业是一种农艺实践，农民不翻耕，而是将前一年的作物留在土地上，这同时也可以蓄水。
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U.S. practice is accompanied by the process of industrialization, agriculture and large-scale operation to become a common trend.