Pathogen infection poses a serious threat to the survival and commercial quality of cultured Paa spinosa, which provide protection as a substitute for wild P. spinosa. The gut microbiota plays vital roles in host health and immunity. To provide guidance for preventing intestinal diseases of artificial P. spinosa culture, we compared gut microbiota compositions of wild and cultured P. spinosa using high‐throughput sequencing. A total of 11,526 operational taxonomic units (OTUs) were identified from 14,043 sequences from each sample. Cetobacterium, PW3 Bacteroides and some unidentified species from Bacteroidales, Rikenellaceae and Clostridiales were significantly increased in the gut microbiota from cultured P. spinosa, whereas Faecalibacterium and unidentified bacteria from Ruminococcaceae were significantly decreased in the gut microbiota from cultured P. spinosa. According to the gut microbiota composition, we hypothesized that the cultured P. spinosa in Jing'an would exhibit a higher risk of pathogenic infection than those in Cili. These results provided a method to forecast the pathogenic infection risk of cultured P. spinosa, which could guide the artificial culture of and prevent diseases in P. spinosa through gut microbiota.

A precise estimation of sediment transport capacity (Tc) is key to establishing process‐based erosion models. However, few data are available for estimating transport capacity on steep slopes and test materials sorted at high coarse grain values of >2 mm. Colluvial deposits with loose, coarse material and steep slopes make up the packed materials underlying the collapsing walls in benggang, which collapse due to hydraulic pressure and gravity. The objectives of this study were to investigate how flow discharge and slope steepness affect Tc and to examine relationships between Tc and flow velocity, shear stress, stream power, and unit stream power for colluvial deposits found on steep slopes. A nonerodible rill flume of 4 m long and 0.12 m wide was used. Slope steepness values ranged from 18% to 84%, and unit flow discharge values ranged from 0.56 × 10−3 to 4.44 × 10−3 m2 s−1. Tc increased as a power function with flow discharge and slope steepness with a Nash–Sutcliffe model efficiency (NSE) value of 0.99, and the effects of flow discharge were stronger than those of slope steepness. Tc was overestimated for a colluvial deposit when the equations of the ANSWERS, Zhang et al. and Wu et al. models were considered and when Tc exceeded 5 kg m−1 s−1, as the slope steepness used in our study was much higher than those used (<47%) in the other models. Regression analyses show that Tc can be predicted from linear equations of flow velocity, stream power, and unit stream power, and Tc can be fit to shear stress with power function equation. Flow velocity optimizes to predict Tc with NSE = 0.97, and stream power and shear stress can also be successfully related to Tc (NSE = 0.91 and NSE = 0.81, respectively); however, unit stream power performs poorly (NSE = 0.67). These results provide a basis for establishing process‐based erosion models on steep colluvial slopes.

We acclimated adult males of three Eremias lizards from different latitudes to 28°C, 33 °C or 38°C to examine whether temperature acclimation affects their thermal preference and tolerance and whether thermal preference and tolerance of these lizards correspond with their latitudinal distributions. Overall, selected body temperature (Tsel) and viable temperature range (VTR) were both highest in E. brenchleyi and lowest in E. multiocellata, with E. argus in between; critical thermal minimum (CTMin) was highest in E. multiocellata and lowest in E. brenchleyi, with E. argus in between; critical thermal maximum (CTMax) was lower in E. multiocellata than in other two species. Lizards acclimated to 28°C and 38 °C overall selected lower body temperatures than those acclimated to 33°C; lizards acclimated to high temperatures were less tolerant of low temperatures, and vice versa; lizards acclimated to 28 °C were less tolerant of high temperatures but had a wider VTR range than those acclimated to 33°C and 38°C. Lizards of three species acclimated to the three temperatures always differed from each other in CTMin, but not in Tsel, CTMax and VTR. Our results show that: temperature acclimation plays an important role in influencing thermal preference and tolerance in the three Eremias lizards, although the degrees to which acclimation temperature affects thermal preference and tolerance differ among species; thermal preference rather than tolerance of the three Eremias lizards corresponds with their latitudinal distributions.

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