彰武农田土壤风蚀物垂直分布规律的研究

利用自制沙尘采集器,通过对3种自然风速天气下所收集风蚀物的分析,研究了农田土壤风蚀物近地表1.5 m的垂直分布规律。结果表明:土壤输沙量随着高度的增加呈下降的趋势,且输沙量随高度变化的规律可以用幂函数近似描绘;风沙流中沙粒的粒径在垂直分布中,随高度的增加,气流中粒径大的颗粒含量逐渐减少,粒径小的颗粒含量逐渐增加,相关分析表明粒径>0.1 mm的颗粒含量与高度在0.05水平呈显著负相关,粒径≤0.1 mm的颗粒含量与高度在0.05水平呈显著正相关;风速在4.8~12.2 m/s范围内,与农田土壤输沙量之间呈指数函数的变化规律;不同耕作方式对输沙量有较大影响,其中,输沙量最大的是花生茬深翻,其次是秋翻地、春浅旋灭茬、秋浅旋灭茬,最小的是旋耕覆盖。

Research of Farmland Soil Erosion on Vertical Distribution Law in Zhangwu County

Analyzing the things collected under the condition of three different wind velocities by a homemade sandy sampler,its vertical distribution law near the surface of farmland was studied.The results showed:the sediment discharge was decreased with height increasing,which could be described by power function;in vertical distribution of sand particle,the relationship of height and the content of bigger particle diameter was the higher the smaller,and the relationship of height and the content of smaller one was just opposite.Relative analysis showed that the relationship of height and particle diameter which bigger than 0.1 mm was significant negative correlation at level 0.05.The others was showed significant positive correlation at the same level;the relationship of soil sediment discharge and wind velocity,which from 4.8 m/s to 12.2 m/s was fitted as the law of exponential function;different tillage patterns had great influence on sediment discharge.The maximal of soil sediment discharge was under the deep tillage pattern of peanuts stubble,followed by plowing in autumn,shallow rotary stubbling in spring,and shallow rotary stubbling in autumn,the minimum was rotary tillage mulch pattern.