东北黑土区农田土壤风蚀的影响因素及其数量关系

发布时间：2018-02-15 12:56

本文关键词： 黑土地退化黑土风蚀风速土壤含水量秸秆覆盖率　出处：《水土保持学报》2017年04期 　论文类型：期刊论文

【摘要】：为明确东北黑土区农田土壤风蚀的主要影响因素,通过室内模拟试验,对比分析了黑土在不同风速(5~14m/s)、土壤含水量(2%~11%)以及秸秆覆盖率(0~80%)下的风蚀速率差异,进而分析了风蚀速率与各因素之间的数量关系。结果表明,黑土起沙风速略大于5m/s,其风蚀速率随风速增大呈指数增加,风速14m/s(含水量2%)时的风蚀速率比8m/s时增加了11.6~42.7倍。黑土风蚀速率随土壤含水量升高呈先增加后降低趋势;在土壤含水量小于5%时随含水量升高而逐渐增加,至含水量5%时达到峰值并逐渐降低,至含水量11%时接近零。秸秆覆盖显著降低了黑土风蚀速率,二者成近似指数函数关系;秸秆覆盖率20%(含水量2%)时的风蚀速率比无覆盖减少了72.6%~92.3%,但秸秆覆盖率由20%增加至80%(含水量2%)后风蚀速率仅降低了0.02~1.20g/(m2·s),幅度有限。研究表明,风速、土壤含水量以及秸秆覆盖率均可显著影响东北黑土区农田土壤风蚀速率,其权重依次为风速土壤含水量秸秆覆盖率。
[Abstract]:In order to determine the main influencing factors of soil wind erosion in the black soil area of Northeast China, the difference of wind erosion rate of black soil under different wind speeds (5m / s), soil water content (2 ~ 11%) and straw coverage (0 ~ 80%) was compared and analyzed through laboratory simulation tests. Furthermore, the quantitative relationship between wind erosion rate and various factors is analyzed. The results show that the wind velocity of sand rising in black soil is slightly greater than 5 m / s, and the wind erosion rate increases exponentially with the increase of wind speed. The wind erosion rate at the wind speed of 14 m / s (water content 2) increased by 11. 6% 42.7 times than that at 8 m / s. The wind erosion rate of black soil increased first and then decreased with the increase of soil water content, and gradually increased with the increase of soil water content when the water content was less than 5. When the water content reached the peak value at 5 and gradually decreased, and near zero at the water content of 11, straw mulch significantly reduced the wind erosion rate of black soil, and the relationship between them was an approximate exponential function. The wind erosion rate at 20% straw coverage (water content 2) was 72.6% lower than that without mulching, but the wind erosion rate decreased only 0.02% 1.20 g / m ~ 2 路s ~ (-1) after increasing straw coverage from 20% to 80 (water content 2). Soil water content and straw coverage could significantly affect the wind erosion rate of farmland in the black soil area of Northeast China. The weight of the soil erosion rate was wind speed soil water content straw coverage.
【作者单位】：中国农业大学资源与环境学院;农业部华北耕地保育重点实验室;黄土高原土壤侵蚀与旱地农业国家重点实验室;
【基金】：中央高校基本科研业务费专项(2017QC048)
【分类号】：S157.1

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