【作者】 赵沛义； 妥德宝； 李焕春； 段玉； 康暄； 弓钦；

【Author】 Zhao Peiyi~1,Tuo Debao~1,Li Huanchun~1,Duan Yu~1,Kang Xuan~1,Gong Qin~2 (1 Inner Mongolia Key laboratory of Dry Farming,Key Observation Station of Ecologic Environment of Ministry of Agriculture, Institute of Resources and environment and Testing Technology,IMAAAHS,Huhhot,010031,China; 2.Wu Lanchabu City Soil and Fertilizer Workstation,Ji Ning 012000,China)

【机构】 农业部农牧交错带生态环境重点野外科学观测试验站,内蒙古旱作农业重点实验室,内蒙古农牧业科学院资源环境与检测技术研究所； 乌兰察布市土壤肥料工作站；

【摘要】 为了探究土壤湿度及物理性沙粒含量对土壤风蚀模数的影响,将人工配制的物理性沙粒含量分别为22.84%、31.31%、43.45%、52.63%、58.80%、67.96%和77.94%七种土壤按照不同水分梯度在内蒙古农业大学研制的0FDY-1.2型风蚀风洞中选择5m/s、6m/s、9m/s、12m/s、15m/s和18m/s风速进行历时10min吹蚀,在风洞轴线距出口1.2m处放置旋风式集沙仪测定垂直方向上20mm、60mm、120mm、180mm、240mm、300mm、400mm、500mm、600mm和700mm10个不同高度的风蚀物收集量,利用MATLAB7.4.0(R2007)软件采用三次样条插值拟合法将旋风式集沙仪不同高度的风蚀物收集量进行积分,通过换算计算土壤风蚀模数(E)。按照土壤风蚀模数大小分①无风蚀,E<0.2g(m2 min)-1;②轻微风蚀,E=0.2-1.0g(m2 min)-1;③土壤风蚀缓增区,E=1.0～2.0g(m2 min)-1;④土壤风蚀增强区,E=2.0～5.0g(m2 min)-1;⑤土壤风蚀极强区,E>5.0g(m2 min)-1进行风蚀强弱分析。结果表明:物理性沙粒含量低于40%时在各种水分条件下集沙仪不同高度风蚀物收集量均很小,风蚀物收集量在空间上利用指数函数和幂函数拟合相关性均很好;物理性沙粒含量高于40%后,风蚀物收集量在空间上呈现幂函数曲线变化规律。9 m/s风速基本上是风蚀物空间动态发生变化的临界点,低于临界风速风蚀物收集量与高度符合指数曲线变化规律,高于临界风速后二者符合幂函数曲线变化规律。集沙仪不同高度的总输沙量随风速的增加而增大,两者符合指数曲线变化关系;输沙量与水分呈负相关关系,水分增大输沙量降低。物理性沙粒含量低于30%的土壤,不会有风蚀现象发生;当物理性沙粒含量大于40%后,土壤容易发生风蚀,而且风蚀程度随物理性沙粒含量的增加而增大,尤其当土壤含水量低于3%时,极易发生风蚀。风速越大土壤风蚀模数越大,风蚀模数与风速按照指数曲线规律进行变化。阴山北麓旱作区冬春季节土壤地表含水量一般维持在3%～4%,土壤的物理性沙粒含量基本在50%～80%,单纯考虑土壤水分和土壤物理性沙粒含量认为阴山北麓旱作区大部分地区都是沙尘暴的发生源。建议通过合理调整种植结构、推行作物残茬覆盖、减少耕翻面积和次数等方式大幅度增加地表覆盖,有效遏制土壤风蚀荒漠化的蔓延。更多还原

【Abstract】 In order to investigate effects of soil moisture and physical sand content on wind erosion modulus,seven degrades of physical sand content（22.84%and 31.31%and 43.45%and 52.63%and 58.80%and 67.96%and 77.94%） with eleven degrades of soil water moisture（0～10%,1%is one step ）were tested in six wind speed（5m/s and 6m/s and 9m/s and 12m/s and 15m/s and 18m/s） in 0FDY-1.2 wind erosion tunnel（made by IMAU）.The wind erosion quantity was measured in ten degrades height （20mm and 60mm and 120mm and 180mm and 240mm and 300mm and 400mm and 500mm and 600mm and 700mm） with cyclone type sand collector which set at 1.2 m distance to the exit of wind tunnel.The data were conversed to wind erosion modulus（E） and analyzed with process cubic spline interpolation with MATLAB 7.4.0（R2007）.There were five wind erosion intensity as following:①None wind erosion E<0.2 g·（m²·min）^-1 and②Slight wind erosion,E=0.2～1.0 g·（m²·min）^-1 and③Slow increasing stage,E=1.0～2.0 g·（m²·min）^-1and④Enhanced stage,E=2.0～5.0 g·（m²·min）^-1 and⑤Very strong stage,E>5.0 g·（m²·min）^-1.The results showed that the wind erosion amount was very small when the sand content was less than 40%whatever the water content and collecting height was.The wind erosion amount changed as an exponential function or an power function when the sand content was less than 40%and as a power function when it was more than 40%.The wind erosion amount was increased with the height as exponential function when the wind speed was slower than 9 m/s and changed with power function when it was faster than 9 m/s.The total wind erosion amount in different heights collector increased with the wind speed increasing as exponential function.Soil sediment discharge increased with the soil water decreasing. There was no wind erosion when the sand content less than 30%,but the wind erosion would increased with the sand content increasing if the content was more than 40%especially the soil moisture was less than 3%.The wind modulus increased with the wind speed as exponential function.The north area of Yinshan Mountain was an occurring source of sandstorm if only considering the soil water and physical sand content,because the soil water content was always less than 3%⁴%in spring and winter and the sand content was more than 50%⁸0%.To contain the wind erosion and desertification several measures were suggested:Adjusting planting structure and covering field with crop straw and decreasing plough and increasing surface covering degree.更多还原