作物残茬对农田土壤风蚀的影响

Effect of Crop Stubble Mulch on Farmland Wind Erosion

通过对不同留茬高度对地表风速的影响以及留残茬(保护性耕作主要方式)、旋耕和常规翻耕3种耕作方式对土壤风蚀的影响进行比较研究,得出如下结果:留茬高度对地表风速的影响程度不明显,仅与地面有无留茬有关,留茬20cm左右即可有效降低地表风速,减少田间扬沙,抵抗土壤风蚀,是比较适宜的留茬高度;留茬(保护性耕作)、旋耕和常规翻耕3种耕作方式对田间扬沙情况的影响差异明显,其中在60cm高度以内,留茬比常规翻耕减少田间扬沙量34.9%,比旋耕方式减少61.5%,因此,留茬(保护性耕作)是一种有效防止农田土壤风蚀的耕作方式。

By observe the effect of the various stubble heights on the wind speed and the effect of wind erosion on the soil under three different tillage forms-stubble mulch(the main type of conservation tillage), rotary plowing and traditional plowing. The results were as follows: The wind speed is less affected by the various stubble heights but more on whether the practice of stubble is applied or not. The appropriate stubble height is around 20 cm, which is high enough to hold down the wind speed, deduce the amount of rising sand and resist the wind erosion on soil. The three tillage forms mentioned above showed a significant difference of their effects on restraining the amount of raising sand in farmland. Below 60cm, the form of conservation tillage (stubble mulch) reduced the amount of raising sand by 34.9% to traditional plowing and by 61.5% to rotary plowing. So stubble mulch is an effective tillage form in controlling sand storm.