【作者】 张莉；

【导师】 郭中领；

【作者基本信息】 河北师范大学 ， 自然地理学， 2022， 硕士

【摘要】 风速数据是土壤风蚀预报模型的主要输入参数之一,高时空分辨率的风速数据能有效提高模型模拟精度。日均风速统计数据或定时观测的风速数据较易获取,但大部分地区并不具备或很难直接获取长时间序列高时空分辨率风速数据。基于以上问题本研究选用修正风蚀模型（RWEQ）和综合风蚀模拟系统（IWEMS）分别从田块尺度和区域尺度探究不同风速数据类型对土壤风蚀模拟的影响。为对比风速处理方法及风速数据时空分辨率对模型模拟结果的影响,分别评估修正风蚀模型（RWEQ）和综合风蚀模拟系统（IWEMS）模型对于各输入参数的敏感性。田块尺度上分别选用中国北方农牧交错带内37个气象站的四类风速数据,分别为逐小时风速数据(24h/d₂₄)、1日4次定时观测风速数据（2:00、8:00、14:00、20:00）（4h/d₄）、用WEPS模型的WINDGEN风速生成法根据1日2类风速数据（日平均风速和最大风速）生成的24小时风速（24h/d₂）,和用线性插值方法根据1日4次定时观测风速数据生成的24小时风速（24h/d₄）的四种情景。区域尺度选取130个（基准气候站和基本气象站）、47个（基准气候站）气象站的风速数据,考虑两种情景,分别为用线性插值方法将1日4次风速数据生成的逐小时风速、用WINDGEN将1日2类风速数据生成逐的小时风速和1日4次定时观测风速数据。风速数据类型的共六种模拟情景。主要研究结论如下:（1）RWEQ模型和IWEMS模型中最敏感的输入参数均为风速,风速数据的变化会影响土壤风蚀模数的估算及风蚀强度的时空变化;其他输入参数如植被盖度、土壤湿度及土壤物理性质等对土壤风蚀的发生有抑制或促进作用。（2）田块尺度上,RWEQ模型和IWEMS模型模拟的严重土壤风蚀气象站基本一致,均分布在毛乌素沙地、浑善达克沙地和科尔沁沙地;在四模拟情景中,逐小时风速的24h/d₂₄情景被认为最接近实际土壤风蚀模数,4h/d₄的模拟结果最大,2h/d₂₄次之,4h/d₂₄最小;在两个模型中,平均风速与土壤风蚀模数成正相关,风速是土壤风蚀的驱动力。（3）在区域尺度,通过不同情景模拟结果发现,两个风蚀模型均能较好的模拟区域土壤风蚀的情况,不同的风速数据模拟的结果与田块尺度的变化基本一致。IWEMS模型估算的土壤风蚀模数大于RWEQ模型模拟的结果,两个模型六种情景模拟的土壤风蚀模数在空间分布和年际变化一致,而在模拟情境中,情景5和情景6模拟的土壤风蚀模数大于情景1和情景2,情景3和情景4模拟的土壤风蚀模数小数情景1和情景2。（4）通过研究发现估算的区域潜在风蚀模数会随气象站点的数量和风速分辨率的提升而增加。另外风速数据的线性插值方法在RWEQ模型IWEMS模型中应用效果不理想,与WEPS模型的WINDGEN风速生成方法相比,线性插值法使地面2米处大于临界起沙风速(5 m·s^-1)风速频率的降低,过低估计风蚀模数和区域土壤风蚀状况。更多还原

【Abstract】 Wind data is one of the essential input parameters in wind erosion model,and with high temporal-spatial resolution can improve the performance of model simulation.However,the limited wind data,such as daily wind speed and frequenctly observed wind data,more easily accessible than high temporal resolution and high spatial resolution wind data in regional.In order to explore the method of temporal interpolation and wind speed data with different spatial-temporal resolution on the model simulation results in field,and regional scale estimated area,the sensitivity analysis of input parameters of two models had been evaluated.The four types of wind data from 37 reference climatological,hourly wind speed,four wind speeds per day（2:00,8:00,14:00,20:00）,hourly wind speed generated by two wind speeds per day（mean&maximum wind speed）and hourly wind speed from four wind speeds per daybe used to estimate the potential wind erosion in field scale.The six scenarios with different wind data and climatological stations from three types wind data have been built,hourly wind speed generated by two wind speeds per day（mean&maximum wind speed）,hourly wind speed from four wind speeds per day and four wind speeds per day from 130 meteorological observing stations（reference climatological station and basic weather station）in regional scale in the Agricultural Pastoral Ecotone of Northern China（APEC）based on the RWEQ and IWEMS.The results revealed as follow:（1）Most sensitive parameters in the RWEQ model and IWEMS models is wind speed.The changed wind speed data will affect the estimation of soil wind erosion and the intensity of temporal-spatial wind erosion;other input parameters such as vegetation cover,soil moisture and soil physical properties can inhibit or promote the occurrence of soil wind erosion.（2）The seriously erosion climatological station are similar,distributed in Mu Us Sandy Land,Horqin Sandy Land and the Hunshan Dake Sandy Land,in RWEQ and IWEMS in field scale.In four scenarios,the results of estimation of wind erosion are presented as 4h/d₄>24h/d₂₄>24h/d₂>24h/d₄,the effecting factors of wind erosion had been counted,the results showed that the positive correlation between mean wind speed and potential wind erosion,and the Significant negative and unrelated correlation between potential wind erosion and vegetation cover and rain or soil moisture in two models.Wind speed was the essential driving factor and vegetation cover and rain or soil moisture have Inhibitory effect.（3）In regional scale,two models can better simulate the soil wind erosion used different wind speed data and the results are consistent with the variation estimated in field scale.The temporal-spatial distribution and interannual variation of potential wind erosion moduls are same between two models,the results of IWEMS over the RWEQ’s soil potemtial wind erosion moduls.But from scenarios,the simulated wind erosion moduls from scenario 5 and scenario 6 are greater than scenario 1 and scenario 2 and scenario 3 and scenario 4 less than scenario 1 and scenario 2.（4）The potential wind erosion of RWEQ enhanced as the number of meteorological stations and wind speed resolution increase.Moreover,compared with WINDGEN in WEPS,the method of linear interpolation is an unsatisfactory in RWEQ,which caused a remarkable reduce of frequency greater than threshold wind speed(5 m﹒s^-1)at 2 m height and the underestimated on potential wind erosion moduls and erosion condition in wind erosion model.更多还原