RWEQ模型中风因子的改进及应用  

Improvement and application of wind factor in RWEQ model

作　　者：巩国丽 刘鑫 要玲 任丽霞 王敏 GONG Guoli;LIU Xin;YAO Ling;REN Lixia;WANG Min(Shanxi Institute of Energy, 030600, Yuci, Shanxi, China;Information Center of Ministry of Ecology and Environment, 100029, Beijing, China;Vision World Technology Co., Ltd,100029,Beijing,China)

机构地区：[1]山西能源学院,山西榆次030600 [2]生态环境部信息中心,北京100029 [3]北京维盛沃德科技有限公司,北京100029

出　　处：《中国水土保持科学》2021年第4期143-148,共6页Science of Soil and Water Conservation

基　　金：山西能源学院院级科研基金项目“山西省矿产资源开发区生态综合探测分析与治理措施研究”(ZB2018002);山西省高等学校科技创新项目资助“RWEQ模型的改进及应用”(2020L0728);国家“十二五”科技支撑计划课题“国家尺度生态系统监测与评估技术集成应用系统”(2013BAC03B00);第二次青藏高原综合科学考察研究资助(2019Q2KK1003)。

摘　　要：风是产生土壤风蚀的前提,实地观测的风速是时刻变化的,模型中需要不少于500个的风速值来支撑,而较高时间分辨率的风速数据难以获取,为此很多文章研究风速降尺度拟合的方法,改进修正方程中风因子估算。本文利用二参数韦伯分布函数、日均风速和日最大风速法分别拟合风速,并与实测结果进行对比研究。此外根据修正后的风速值代入RWEQ模型中得到我国北方的风因子空间分布。结果表明:二参数韦伯分布函数拟合风速所求的风蚀力与实测的风速所求的风蚀力存在误差,相对误差值从0.19到0.95,平均相对误差值达到0.52;利用二参数韦伯分布函数拟合所得风蚀力被低估;日均风速和日最大风速法也未能很好地拟合风速,但用该方法拟合风速计算结果风蚀力与实测风速计算结果风蚀力存在相关性,可利用此相关性反推出实测风蚀力;从利用2000—2010年3月份的实测风速拟合所得风因子值来看,我国内蒙古高原上各大沙地的风因子值较高,东北及青藏高原高山地带等地区的风因子值也较高。[Background]Wind is the most important driver of soil wind erosion and the most important input parameter in the RWEQ(revised wind erosion equation)model for quantitatively estimating wind erosion.The actual wind speed changes all the time.Substituting the average wind speed into the model will make the calculated wind erosion less.Therefore,the model requires no less than 500 wind speed values to estimate the wind factor.However,wind speed data with high temporary resolution is difficult to acquire.For all this,how to select downscaling techniques for wind speed data is worth studying.[Methods]Two-parameter Weibull distribution model,as well as the fitting method of daily average and maximum wind speed were used to fit wind speed respectively.The fitting results of the two methods were compared with the measured results respectively.The measured data were the observed values of national meteorological stations,including daily four periodic wind speed values,daily mean and daily maximum wind speed values.According to the comparison results,the wind speed downscaling method was modified,and the revised wind speed values were substituted into the RWEQ model to obtain the spatial distribution of wind factors in North China.[Results]1)There was an error in the wind erosion force between by the two-parameter Weibull distribution model and by the measured wind speed,the relative error value was in 0.19 to 0.95,the mean relative one reached 0.52.Regression analysis results showed that the correlation coefficient between two of them reached 0.97,and the significance level P<0.01.2)For the wind speed value>5 m/s,the relative error value between the fitting results and the measured results were 0.01-0.18,and the mean one was 0.09,correlation coefficient reached 0.82,and the significance level P<0.01.The fitting result in the high wind speed area(>5 m/s)was small with a slope of 0.74.3)The fitting method of daily average and daily maximum wind speed also couldn't be directly applied to estimate wind erosion in North China.H

关 键 词：土壤风蚀 RWEQ模型 二参数Weibull分布模型 风速降尺度 风因子 

分 类 号：K903[历史地理—人文地理学]