5. Conclusions
This research analyses the common algae and moss biological soil crusts in the typical farming-pastoral ecotone. Using wind tunnel tests, the effects of wind speed and coverage on wind erosion and particulate matter emissions were studied and the relationship between particulate matter emission and wind erosion was analyzed. From the perspective of wind erosion, the influence of wind speed and coverage is similar. However, from the perspective of particulate matter emissions, the influence of coverage is always higher than wind speed, which is determined by the structure and nature of the biological soil crust itself. The proportion of particulate matter emitted from biological soil crusts in the amount of wind erosion has a significant behavior. Although the overall particulate matter emissions increase with increasing wind speed, the proportion of particulate matter emissions in the wind erosion is inversely proportional to the wind speed and coverage due to the corresponding changes in the amount of wind erosion. According to the trend of the proportion with wind speed, the particle emission capacity of moss crust is directly proportional to the particle size and inversely proportional to the coverage. The particle emission capacity of algae crust is proportional to the particle size, but its relationship with coverage is not regular. The results of this study can be relevant for the control of wind erosion and particulate matter emissions.