基于风蚀模型的张家口市风力侵蚀时空分布特征

Spatial temporal variation characteristics of wind erosion in Zhangjiakou City,northern China,using a wind erosion model

为明确张家口市风蚀现状,利用遥感影像、数字高程模型(DEM)以及土地利用等数据,结合风蚀预报经验模型,计算了张家口市2005-2015年近10年风力侵蚀强度时空分布特征。结果表明:1)该市土壤风力侵蚀主要为轻度侵蚀和中度侵蚀,2005年轻度侵蚀面积11784.90 km^2,占总面积的32.41%,中度侵蚀面积2461.93 km^2,占总面积的6.77%,而2015年仅有轻度侵蚀,面积为7322.08 km^2,占总面积的20.14%,2005-2015年,该市风力侵蚀面积呈下降趋势;2)中度风力侵蚀主要集中分布在康保、张北、尚义等县;3)该市风力侵蚀主要集中在坝上地区,2005、2010、2015年风蚀面积分别为9520.47、8086.85和5674.71 km^2,而坝下地区2005、2010、2015年风蚀面积分别为4762.36、2808.34和1647.37 km^2,呈逐渐下降趋势;4)耕地和草地的风蚀面积及其占比均较高,且各种土地利用类型均以轻度侵蚀为主,不同土地利用类型风蚀面积也均呈逐渐减少趋势。研究结果可为张家口市水土流失治理以及生态环境建设提供科学依据。

The spatial temporal variation characteristics of wind erosion during 2005,2010 and 2015 in Zhangjiakou City were assessed using a wind erosion model,combined with remote sensing images,digital elevation model(DEM)data and land use data.The results showed that slight erosion was estimated at 11784.90 km^2 and accounted for 32.41% of the total area in 2005,while moderate erosion was estimated at 2461.93 km2 and accounted for 6.77% of the total area.This indicated that slight and moderate erosions were the primary wind erosion intensities in Zhangjiakou City.In 2015,slight erosion was estimated at 7322.08 km^2 and accounted for 20.14% of the total area.This indicated that the area of wind erosion has a different intensity,showing a downward trend in Zhangjiakou City from 2005 to 2015.Moderate wind erosion was mainly distributed in Kangbao County,Shangyi County and Zhangbei County of Zhangjiakou City.Wind erosion area in Bashang Region was 9520.47 km^2,8086.85 km^2 and 5674.71 km^2 in 2005,2010,and 2015,respectively,In the Bacia Region,it was 4762.36 km^2,2808.34 km^2 and 1647.37 km^2 in the Baxia Region in the 2005,2010,and 2015,respectively.These result indicated that the area of wind erosion gradually declined in the Bashang and Baxia Region.The area of wind erosion and the proportion of wind erosion in each land use type was relatively higher in grassland and cultivated land than in other land use types.The intensity of wind erosion for each land use type was high for slight erosion.To conclude,the area of wind erosion for each land use type gradually declined from 2005 to 2015.These results could provide a scientific basis for soil erosion control and ecological environment construction in Zhangjiakou City in the future.