Spatial and Temporal Variation of Wind Erosion Climatic Erosivity and Its Response to ENSO in the Otindag Desert, China

Lou Lou,Cai Cai,Wang Wang

doi:10.3390/atmos10100614

Abstract

Wind erosion is a major cause of soil losses in China’s drylands which is further stimulated by climate variability and fragile ecological conditions. Climatic erosivity is an important index of wind erosion, therefore, evaluation of its spatiotemporal variations and relationship with the El Niño–Southern Oscillation (ENSO) will provide a theoretical basis for the comprehensive management and prevention of soil erosion. In this study, by using the climatic erosivity equation, geographic information system (GIS) and geostatistical analysis, we quantified the climatic erosivity, explored its spatiotemporal variations, and detected the effects of the Multivariate ENSO Index (MEI) on climatic erosivity in the Otindag Desert during the period of 1980–2016. The results indicated that the climatic erosivity (C-factor value) ranged from 82–445, and it decreased from the western margin to the eastern margin of the desert. The climatic erosivity showed a significant downward trend at seasonal and annual scales (p < 0.05). As far as spring, autumn and annual climatic erosivity, the whole region showed a downward trend, however, the summer and winter climatic erosivity varied spatially, in which the central and western regions showed a downward trend, but the eastern region showed an upward trend. The results showed that the average climatic erosivity is weaker during La Niña events than during El Niño events. The climatic erosivity recorded by 14 of the 20 meteorological stations, all located in central and west regions, exhibited a significant correlation with MEI (p < 0.05). The ENSO has a significant impact on climatic erosivity.

Highlights

Wind erosion causes land degradation in arid regions and is affected by natural and human factors such as climate, landscape, farming, grazing and other factors
The lower values were mainly distributed in the eastern Otindag Desert, while the southwest had
The climatic erosivity mean value in Tarim Basin [43] and western Inner Mongolia [11] were 17.5 and 154.5, respectively, which indicated that the Otindag Desert has higher risk of wind erosion desertification than other areas of China, and more attention should be focused on forecasting wind erosion and combating desertification in the region

Summary

Introduction

Wind erosion causes land degradation in arid regions and is affected by natural and human factors such as climate, landscape, farming, grazing and other factors. The major alterations were associated with the frequency and intensity of wind events and precipitation patterns These changes influence the wind erosivity, and adversely affect the land erodibility [2,3,4,5,6]. There are various models to quantify wind erosivity, among which the wind erosion equation (WEQ) and the revised wind erosion equation (RWEQ) are well-known and widely used [7,8]. These models require multiple inputs, such as soil, vegetation types and climate data. Due to the data limitations, these models are generally unsuitable analyses of wind erosion at large-scale

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Discussion

Conclusion