与以往在收获后犁地而破坏土壤不同，农民在种植下一季作物时，将残茬，比如玉米秸秆或麦茬，留在田里。这种做法提高了土壤保持水分的能力，使作物在极端的干旱天气时更好地生长。这种方法还提供了其他好处：

• 根据不同的耕作方法以及保护土壤不受风雨侵蚀的残茬的数量，土壤受侵蚀的程度最多可减少60%。
• 给土壤添加健康的有机物。
• 减少拖拉机在田地中往返的次数，这样可以节省用于燃料和种植的花费。
• 减少灰尘和柴油排放对空气的污染。
• 减少可能干扰植物生长的土壤板结。

时间证明，保护性耕作，加上轮作和使用覆盖作物，能够增加收成，并能增加土壤养分。联合国粮食和农业组织(Food and Agriculture Organization)在坦桑尼亚进行了一项实例研究，结果显示，到第六季时，农作物的产量已经从一英亩生产三袋玉米和一两袋豆子，增加到30袋玉米和10袋豆子（一英亩约合0.4公顷）。

Want healthier soil? Don’t plow.

As farmers adapt to the effects of climate change, they want cost-effective ways to maximize available water and improve soil. More and more farmers are discovering conservation tillage (also known as conservation agriculture).

Instead of disturbing the soil by plowing after a harvest, the farmers leave residue, such as maize stalks or wheat stubble, on a field as they plant the next season’s crop. The practice boosts the soil’s ability to hold moisture, allowing crops to grow better during dry-weather extremes. The method also offers other benefits:

• Reduces soil erosion by as much as 60 percent, depending on the tillage method and amount of residue left to shield soil from rain and wind.
• Adds healthy organic matter to soil.
• Requires fewer tractor trips across the field, which means less spending on fuel and planting.
• Reduces air pollution from dust and diesel emissions.
• Reduces soil compaction, which can interfere with plant growth.

Over time, conservation tillage accompanied by crop rotation and the use of cover crops has been shown to increase harvest yields, in addition to enriching soil. The U.N.’s Food and Agriculture Organization did a case study in Tanzania that showed that, by the sixth season, crop yields had increased from three bags of maize and one or two bags of beans per acre to 30 bags of maize and 10 bags of beans per acre (one acre is .4 hectare).