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Loesses are widely distributed all over the world, especially in China. Meanwhile, long-term agricultural irrigation and extreme climate changes have led to frequent geological disasters in the Heifangtai area of Lanzhou, Gansu, China. Of these, landslides are one of the most frequent types of disasters that are harmful to humans and the environment. A landslide is closely related to the lithology, structure, and groundwater of the site and consists of a combination of structure units divided by discontinuities, such as faults, joints, and fissures. Therefore, geological surveys, engineering drilling, and trenching are typically used to identify the stratum lithology, structure, and groundwater in order to visually display underground information within a limited depth range. However, these methods have disadvantages. In particular, geological surveys can only describe geological phenomena on the surface, while the cost of drilling and trenching may be high, along with the inefficiency of exploration. In this research, the integrated geophysical exploration method was used to analyze the hidden joints, cracks, and other discontinuities and geophysical features of the discontinuities. The results were verified by trench exploration, and large amounts of underground information were obtained, especially the spread and distribution of discontinuities in landslide areas. Such information can be effectively used for carrying out and providing meaningful experiences and lessons in future comprehensive geophysical processing and interpretations related to the prediction and evaluation of landslides. [ABSTRACT FROM AUTHOR]

Enterocytozoon bieneusi , an obligate intracellular pathogen, can infect various hosts. In this study, 3527 dairy cattle fecal specimens were collected from different geographic locations in China (including 673 from Shandong province, 1,440 from Guangdong province and 1,414 from Gansu province) and examined for the presence of E. bieneusi using polymerase chain reactions targeting the ribosomal internal transcribed spacer (ITS). The dominant genotypes identified were further subtyped by multilocus sequence typing. The overall prevalence of E. bieneusi was 14.2% (501/3527), with a significant difference in prevalence among the different geographical locations (P < 0.001). Our logistic regression analysis showed that all four variables (farming model, location, age, and clinical manifestations) had strong effects on the risk of contracting E. bieneusi. Sequence analysis revealed 11 genotypes: eight known genotypes (J, I, BEB4, BEB10, D, EbpC, CM19, and CM21) and three novel genotypes (named here as CGC1, CGC2, and CGC3). Genotypes J and I, the commonest, were found on all farms across the three provinces. Our linkage disequilibrium analysis showed a clonal population structure in the E. bieneusi dairy cattle population but the ITS genotypes had different population structures. Phylogenetic and haplotype network analysis showed the absence of geographical segregation in the E. bieneusi dairy cattle populations. Instead, they revealed the presence of host adaptation to the E. bieneusi populations in various animals. Our findings augment the current understanding of E. bieneusi transmission dynamics. [ABSTRACT FROM AUTHOR]