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Abstract: The objective of this study was to assess the genetic diversity and population structure of goats in the Yangtze River region using microsatellite and mtDNA to better understand the current status of those goat genetic diversity and the effects of natural landscape in fashion of domestic animal genetic diversity. The genetic variability of 16 goat populations in the littoral zone of the Yangtze River was estimated using 21 autosomal microsatellites, which revealed high diversity and genetic population clustering with a dispersed geographical distribution. A phylogenetic analysis of the mitochondrial D‐loop region (482 bp) was conducted in 494 goats from the Yangtze River region. In total, 117 SNPs were reconstructed, and 173 haplotypes were identified, 94.5% of which belonged to lineages A and B. Lineages C, D, and G had lower frequencies (5.2%), and lineage F haplotypes were undetected. Several high‐frequency haplotypes were shared by different ecogeographically distributed populations, and the close phylogenetic relationships among certain low‐frequency haplotypes indicated the historical exchange of genetic material among these populations. In particular, the lineage G haplotype suggests that some west Asian goat genetic material may have been transferred to China via Muslim migration. [ABSTRACT FROM AUTHOR]

The methane isothermal adsorption experiment was conducted on the Lower Silurian marine shale of the Longmaxi Formation from the Upper Yangtze Platform, China, at pressures up to 10.94 MPa and temperatures of 30 °C and 39 °C to investigate the key factors affecting its methane adsorption capacity. Basic shale reservoir characteristics were obtained using total organic carbon measurements, thermal maturity assessment, X-ray diffraction, and nitrogen adsorption. An abundance of organic matter in the reservoir with total organic carbon (TOC) ranging between 0.49 and 4.8 wt% was overmature. The matrix minerals mainly consisted of clay (16%–33%) and quartz (37%–53.9%). The Brunauer–Emmett–Teller (BET) surface areas of the shale samples varied from 6.34 to 21.3 m 2 /g. The Langmuir-based absolute adsorption model was used to correct the measured adsorption isotherms into absolute adsorption isotherms, which represented the actual adsorption. Furthermore, the Langmuir volume was in the range of 1.04–5.36 m 3 /t. Shale gas adsorption capacity presented a significantly positive correlation with an abundance of organic matter that provided a larger BET surface area. The absence of apparent correlation with the clay indicated that the clay did not significantly contribute to the gas adsorption capacity in the shale samples. Variations in temperature and pressure were also key factors affecting shale gas adsorption capacity. Therefore, TOC, temperature, and pressure were optimized to establish the forecast model, combined with multiple regression methods and a set of cited data. The results of the isothermal adsorption experiment in this study were used to verify the model's feasibility for predicting the shale gas adsorption capacity of the Longmaxi Formation. The predicted results were highly correlated with the actual measured results, with a correlation coefficient as high as 0.9887. The function of shale gas adsorption capacity derived and analyses employed in this study can be used to illustrate the impact of pressure and temperature regimes on shale gas adsorption capacity, given varying abundance of organic matter and compositions of matrix minerals. [ABSTRACT FROM AUTHOR]

Phosphorous (P) is an essential nutrient in soil which can lead to eutrophication when eroding into rivers or lakes. As a new method to represent soil properties, fractal theory was applied to study soil characteristics and related process. To understand the correlation of total soil P (TSP) and fractal dimension ( D) with the effect of soil depth and slope gradient, soil grid samples were collected at 0-10, 10-20 and 20-40 cm depths in Yingwugou watershed, Yangtze River, China. The physico-chemical properties of the samples were analyzed to determine the TSP content and D. Fractal scaling theory was then applied to establish the relationship between D and TSP. With silt as the dominant particle size, the D values of the study area were in the range of 2.42-2.55. On the flat ground, more fine particles (clay and silt) were reserved and on the contrary relatively high content of coarse sand was retained on steep slope. D values decreased with slope and soil depth increased. The average TSP contents of the three layers were 0.65, 0.63 and 0.57 g/kg for 0-10, 10-20 and 20-40 cm, respectively, showing a decreasing tendency with increased soil depth. With increasing slope gradient, the TSP contents decreased first and then increased slowly. The TSP contents were positively related to silt content ( P < 0.05) and clay content ( P < 0.05) and negatively associated with sand contents ( P < 0.01). There was an one-dimensional linear relationship ( n = 530, R = 0.16, P < 0.01) between TSP content and D values. The correlation would improve when concrete slope was taken into account. To better understand and control soil erosion, the relationship between D value and soil nutrients deserves more attention. [ABSTRACT FROM AUTHOR]

Two progeny populations of upland cotton derived from mass selection-mass crossing, MSF and its family lines MSF, were generated from 17 hybrid cotton lines derived from regional trials conducted in the Yellow River basin and Yangtze River basin in China. These populations were used to verify 39 reported molecular markers that were related to quantitative trait loci (QTLs) for Verticillium wilt resistance of cotton. Only 12 of 39 markers were polymorphic; 19 had no polymorphisms, and amplification failed for eight markers. The differences in disease grades of aa/AA genotype individuals for five markers, BNL3241, NAU1225, NAU1230, JESPR153, and BNL3031, reached either significant or highly significant levels in at least one population. These markers can thus be effectively used for marker-assisted selection (MAS) of the target trait. Especially for JESPR153 and BNL3031, the differences in disease grades of aa/AA genotype individuals both reached either significant or highly significant levels in the two populations. These two markers should be given preferential consideration when undertaking MAS. The two flanking markers were more effective than the single flanking marker for MAS of single-loci QTL. The selection effect will be greatly enhanced through a reasonable allocation of marker combinations for multi-locus QTL polymerization. When using multi-locus markers for multi-locus QTL-assisted polymerization breeding, the selection effect can be improved progressively by increasing the number of polymerization markers. The possible interaction of different QTLs or genetic backgrounds does not influence the selection effect. A combination of resistant genotypes and disease grade performance enabled final selection of three individuals resistant to Verticillium wilt. [ABSTRACT FROM AUTHOR]

The Elongate loach ( Leptobotia elongata) belongs to family Cobitidae, which is endemic to the middle and upper reaches of the Yangtze River in China. In this study, the complete mitochondrial genome of L. elongata was sequenced. It was determined to be 16,591 bases. The nucleotide sequence data of 12 heavy-strand protein-coding genes of L. elongata and other 12 Cobitidae species were used for phylogenetic analyses. Trees constructed using Bayesian and maximum parsimony showed a similar topology demonstrating that L. elongate was clustered in subfamily Botiinae being sister to the subfamily Cobitinae. The trees also suggested that the genera Cobitis were polyphyletic. [ABSTRACT FROM AUTHOR]