not-yet-known not-yet-known not-yet-known unknown The brush straw checkerboard barrier offers a novel approach to sand control and features 60% higher design efficiency and a longer lifespan of 6 years compared to the traditional artificial straw checkerboard barrier. The wind tunnel test and field observation confirmed that the brush straw checkerboard barrier has high sand fixation efficiency. But how do these two sand barriers perform in terms of restoring soil function? How does the effectiveness of restoring soil function change as the service life of the straw checkerboard barrier increases? These questions still need to be clarified further. This study, conducted in Zhongwei, Ningxia, China, examined plots with brush straw checkerboard barrier, artificial straw checkerboard barrier, and bare sand. The results show that the brush straw checkerboard barrier is superior in improving soil moisture, organic matter, total nitrogen and electrical conductivity compared to the artificial straw checkerboard barrier. In addition, the brush straw checkerboard barrier has a positive impact on microbial diversity and community composition. Increasing sand fixation year through the brush straw checkerboard barrier correlates with improved soil properties and microbial indexes, suggesting that it has the potential for widespread application in desertification mitigation.

Preferential flow plays an important role in the ecosystem. In order to understand the influence of enclosure on the root-soil structure in the preferential flow region, and to understand the difference of root-soil structure between the preferential flow region and the matrix flow region. In this paper, the soil in the preferential flow region of Caragana korshinskii shrub under enclosure or grazing measures in Yanchi, Ningxia, China was selected as the research object. The geometric distribution and topological indexes of root-soil structure (aggregates, macropores and roots) were obtained by CT scanning and three-dimensional image processing. The results showed that the enclosed natural grassland had the highest staining area ratio (40.38%) and staining depth (271 mm). The distribution of soil aggregates and macropores in grazing artificial C. korshinskii shrub and enclosed natural C. korshinskii shrub was more uniform. Enclosure significantly reduced the number density and volume density of soil aggregates, macropores and roots in the preferential flow region (p<0.05). Compared with the matrix flow region, the number density of soil aggregates in the preferential flow region increased significantly (p<0.05), and the average equivalent diameter decreased significantly (p<0.05). Enclosure negatively affects soil aggregates and macropores. Aggregates directly promote the preferential flow process, and macropores indirectly affect the preferential flow process through aggregates. Clarifying the relationship between enclosure, root-soil structure and preferential flow can provide a basis for vegetation restoration management in arid and semi-arid areas.