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Wind regime, sand drift potential and sand transport amount are important indicators to evaluate regional blown sand activities. This paper took Ketu sandy land on the eastern shore of Qinghai Lake as study area. The sand transport amount data were collected monthly in 2013-2014 and 2016-2017 with 16-azimuth sand collector, and data of local wind velocity and direction were used to compare and analyze the typical blown sand activities. The results were as follows: (1) In 2013-2014, the mean wind velocity in the study area was 2.79m/s and the frequency of sand-driving wind was 6.76%. While they were 2.63m/s and 6.13% in 2016-2017, respectively. (2) The directions of the sand-driving wind in two years were similar, clearly from WSW-WNW and ESE-SSE. The frequency of western wind increased whereas the frequency of southeastern wind decreased. (3) The seasonal variation of sand drift potential in two years were similar with the largest in spring and the smallest in summer. According to the annual variation trend of sand drift potential, the study area was belonging to low wind energy environment. (4) There is a significant difference in sand transport amount between the two years. The amount in 2016-2017 was 77.18kg less than that in 2013-2014, while the distribution of sand transport amount was similar. The increase of vegetation coverage in this area is the main reason for the decrease of sand transport amount.

The morphology and stability of concave surface of the straw checkerboard barriers are the fundamental guiding principles of exploring the mechanism of erosion and deposition, evaluating effectiveness and life period, and optimizing the physical structures of the sand barriers. Especially, in alpine sandy land, characteristics of erosion (deposition) and capacity for anti-erosion and sand burial of straw checkerboard barriers are significantly different from the arid and semi-arid desert regions. Erosion (deposition) measurements and wind–sand observations for different specifications (1 m × 1 m, 1.5 m × 1.5 m and 2 m × 2 m) and slope positions (toe, middle and top of the windward areas) of wheat straw checkerboard barriers were adopted in the eastern shore of the Qinghai Lake study area. The different sizes of straw checkerboards at different windward areas have distinctly erosive and depositional stability and intensity. Including the checkerboards with 1.5 m × 1.5 m (medium) size at the middle and top, 1 m × 1 m (small) size at the top and 2 m × 2 m (large) size at the toe, all the erosion (deposition) coefficients are between 0.09 and 0.11, while their intensities of accumulation are relatively steady (70–90 kg m−2), which are the easiest to form stable concaves, and the heights of the barriers change least. Nevertheless, the concaves with small size at the toe are seriously buried, but eroded in the center of some checkerboards with large size at the top, which lead to a short protective period within 3 years and an unbalance between erosion and deposition. Moreover, the transects of erosion (deposition) dominated by southwesterly and northwesterly winds reflect the different intensities of erosion (deposition) at various orientations. On the transect of the NW–SE orientation, at the dune section, each square in the NW direction is strongly accumulated, and the center–SE azimuth is weakly eroded. Usually, deeper accumulation in the center of transects happen in those checkerboards with smaller size and lower terrain slope, which is mainly caused by an obviously positive correlation between the northwest and southwest wind velocity and the erosive depth, and the same is true with the wind frequency (all correlation coefficients are between 0.85 and 0.95). Taking the characteristics of erosion (deposition), sand protection benefits and costs of all types into account, large size at the toe and medium size at the middle of windward slope are the most practical combinations, while small size is suitable to play an emergency treatment role in some extremely serious hazard areas in alpine sandy land.