基于不同风蚀模型的区域土壤风蚀变化及影响因素研究——以内蒙古自治区为例

基于遥感数据、气象数据等,利用RWEQ模型和风蚀预报模型对内蒙古自治区2000—2017年土壤风蚀进行评估并分析其驱动因素。结果表明：（1） RWEQ模型（R²=0.85,P<0.01）和风蚀预报模型（R²=0.43,P<0.01）的预测值与¹³⁷Cs示踪技术风蚀的值具有较好的相关性,其中RWEQ模型预测精度更好。（2）时间上,RWEQ和风蚀预报模型模拟的结果均表明2000—2017年内蒙古自治区土壤风蚀呈下降的趋势,下降趋势分别为0.73,1.18 t/（hm²·a）,2个模型模拟的土壤风蚀模数在2011年均达到最低值。空间上,2000—2017年,2个模型的模拟结果均表明内蒙古自治区土壤风蚀以微度和轻度侵蚀为主,其中剧烈侵蚀在整个研究区的占比较小（RWEQ 1.79%,风蚀预报模型5.45%）,主要分布于北方风沙区的西南部。趋势上,89.74%（RWEQ）和72.05%（风蚀预报模型）的土壤风蚀模数呈下降趋势,其中显著降低的区域主要分布于北方风沙区的巴丹吉林沙漠和乌兰布和沙漠。（3）大风天数对土壤风蚀具有显著影响,随着大风天数的增多,土壤风蚀呈显著上升趋势,植被覆盖度和降水量的增长在一定程度上可抑制土壤风蚀的进程。

Study on Regional Soil Wind Erosion and Its Influencing Factors Based on Different Wind Erosion Models-Take Inner Mongolia Autonomous Region as An Example

Based on remote sensing data and meteorological data, RWEQ model and wind erosion prediction model were used to evaluate soil wind erosion and analyze its driving factors in Inner Mongolia Autonomous Region from 2000 to 2017. The results showed that: (1) RWEQ model (R²=0.85, P<0.01) and wind erosion prediction model (R²=0.43, P<0.01) had a good correlation with ¹³⁷Cs tracer wind erosion, and RWEQ model had a better prediction accuracy. (2) In terms of time, the simulation results of RWEQ and wind erosion prediction model showed that the wind erosion in Inner Mongolia Autonomous Region showed a decreasing trend from 2000 to 2017, and the decreasing trend was 0.73 t/(hm²·a) and 1.18 t/(hm²·a), respectively. The wind erosion modulus of soil simulated by the two models reached the lowest value in 2011. Spatially, from 2000 to 2017, the simulation results of the two models showed that the soil wind erosion in Inner Mongolia Autonomous Region was dominated by slight and light erosion, and the severe erosion accounted for a relatively small proportion in the whole study area (RWEQ: 1.79%, wind erosion prediction model: 5.45%), which was mainly distributed in the southwest of the northern sandstorm area. The wind erosion modulus of 89.74% (RWEQ) and 72.05% (wind erosion prediction model) showed a decreasing trend, and the significantly decreasing areas were mainly distributed in the Badain Jaran Desert and Ulan Buhe Desert in the wind-swept area of northern China. (3) Wind erosion was significantly impacted by the windy days. With the increase of windy days, soil wind erosion showed a significant upward trend, and the increase of vegetation coverage and precipitation could inhibit the soil wind erosion to a certain extent.