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[Objective] To study the bacterial community structure in sediments of "shellfish-fish-grass" productive wetlands. [Method] The IIlumina-MiSeq high-throughput sequencing technology was used to analyze the bacterial community structure in sediments of different units. [Result] The diversity and richness of the bacterial community were significantly higher in the unit composed of juvenile shellfish and high-density shellfish purification unit than in the other treatment units. Proteobacteria, Chloroflexi, Acidobacteriota, Actinobacteriota and Bacteroidota were the dominant phylum of the bacterial community in the sediments. Redundancy analysis showed that the main driving factors of the change of bacterial community was the total phosphorus. [Conclusion] The shellfish placed in the wetland can reduce the nitrogen and phosphorus content in the sediment, and the diversity and richness of the bacterial community in the sediment can be improved through the bioturbation of the shellfish, and the results of this study provide a scientific basis for the treatment of aquaculture tailwater in the "shellfish-fish-grass" productive wetlands. [ABSTRACT FROM AUTHOR]

By analyzing the changes of Saccharomyces cerevisiae fortification on the microbial composition and volatile metabolites of Nong-flavour fermented grains, the disturbances of the microbial ecological network, volatile metabolites and the potential metabolic functions of the microbial community were explored. A strain of Saccharomyces cerevisiae Y1 isolated from nong -flavour fermented grains fermented was used to disturb the solid -state fermentation of fermented grains, and the composition of microorganisms and volatile metabolites were studied by high-throughput sequencing technology and headspace solid-phase microextraction-mass spectrometry technology, respectively. The random forest learning algorithm was used to calculate the biomarkers between the experimental group and the blank group, and the differences in the microbial ecological network between the experimental group and the blank group were analyzed based on the construction of a co-occurrence network model. PLS-DA analysis and Spearman correlation were used to analyze the differences of volatile flavor compounds, the correlation of differential metabolites and biomarkers, respectively. Finally, potential functional changes were analyzed by PICRUST2 functional prediction and pathway enrichment. The results showed that 5 bacteria and 15 fungi can be used as biomarkers to characterize the microbial composition of fermented grains disturbed by Saccharomyces cerevisiae, and also increased the complexity of the microbial ecological network. Meanwhile, the composition of volatile metabolites was altered, with 18 differential metabolites, and the content of some volatile metabolites was improved. The vast majority of biomarkers were significantly associated with differential metabolism. In addition, the perturbation effect of Saccharomyces cerevisiae resulted in 180 up-regulated genes and 46 down-regulated genes in the microbial community, most of which were related to the metabolism of substances. These results provide a basis for the application of Saccharomyces cerevisiae in Baijiu fermentation and the optimization of the fermentation process of fermented grains. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Scientiarum Naturalium Universitatis Sunyatseni / Zhongshan Daxue Xuebao is the property of Sun-Yat-Sen University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The transformation mechanism of muddy carbonate rock by the coupling of bioturbation and diagenesis was studied based on core, cast thin section and physical property data of Cretaceous strata in the Mesopotamia Basin, the Middle East. There are 3 ways of biological transformation of rocks: (1) The living creatures transformed formations mechanically to make the rocks looser and intergranular pores increase. (2) After formation, burrows were backfilled with coarse-grained debris, and then unsaturated fluid infiltrated into the burrows during the penecontemporaneous period, resulting in dissolution. (3) Chemical alteration occurred in abandoned burrows and dolomitization produced a large number of intercrystalline pores. The coupling of bioturbation and dissolution occurred mainly in the penecontemporaneous phase, and was controlled by rock type, sea level decline, burrow abundance, infillings, and water environment etc. As the burrows had better physical properties than the matrix, unsaturated fluid preferentially migrated along the burrows, leading to dissolution and expansion of the burrows first and then dissolution of the matrix. The coupling of bioturbation and dolomitization occurred mainly in the burial phase. The rich organic matter and reducing bacteria in the burrow provided material basis, reducing conditions and alkaline environment for dolomitization. The metasomatism in the penecontemporaneous period had little effect on the physical properties of the burrows. When the burrows were separated from the deposition interface, equimolar metasomatism occurred in the burrows in a closed environment, forming euhedral fine-crystalline dolomite with intercrystalline pores. The transformation degree of bioturbation to muddy carbonate reservoir depends on rock type, density, connectivity, infillings and structure of the burrows. With the increase of the carbonate mud content, the improvement to rock physical properties by bioturbation becomes more prominent. When the burrows are filled with coarse-grained debris or fine-crystalline dolomite, the greater the density, the higher the connectivity, and the lower the tortuosity of burrows, the better the physical properties of the muddy carbonate rocks are.

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bioclastic limestone of Cretaceous Mishrif Formation in M oildeld, Iraq, has strong heterogeneity， and the problem in the process of development is serious. Based on the core observation，cast thin section and experiment data，the heterogeneity genesis was analyzed. The results show that the reservoirs of Mishrif Formation in M oiltield are mainly controlled by sedimentation，bioturbation， diagenesis， and sea level cycles. Sedimentation controls the structural components and original physical properties of rocks, and affects the subsequent diagenetic evolution； bioturbation transforms the rock structure, causes the structure to loosen, and provides seepage channels for diagenetic fluids； diagenesis controls the transformation trend of rocks physical property； sea level cycles cause the change of sediment facies, and control the marine diagenetic environment and meteoric freshwater diagenetic environment. The rocks developed in high-energy sedimentary environment have high content of grain fraction, and the original physical properties are good. During the sea level decline, the upper part ofthe shoal is preferentially leached, while the lower part is strongly cemented, and the reservoir physical properties are polarized, thus high-quality reservoirs are usually associated with physical interlayers. The rocks developed in low-energy sedimentary environment have high content of argillaceous and poor physical properties. However, the bioturbation is widely developed, the physical properties of the burrow are usually higher than that of the substrate. The sea level decline causes the rocks to be in the meteoric freshwater diagenetic environment, and the dissolute fluid can infiltrate the burrows and effectively improve the physical properties. The Mishrif Formation has multiple stages of sea levll cycles, the sedimentary environment evolves rapidly, the diagenetic environment changes continuously, the distribution of biological burrow is random, and reservoirs with different genesis are stacked each ｔｈｅｒ，ｗｈｉｃｈｒｅｓｕｌｔｉｎｓｔｒｏｎｇｖｅｒｔｉｃａｌｈｅｔｅｒｏｇｅｎｅｉｔｙｏｆｔｈｉｃｋｂｉｏｃｌａｓｔｉｃｌｉｍｅｓｔｏｎｅｒｅｓｅｒｖｏｉｒｓ. [ABSTRACT FROM AUTHOR]

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By using microcosm tracer technique,the bioturbation of macrobenthos Helice tientsinensis, Nereis diversicolor, Bullacta exarata, and Cyclina sinensis on the sediment in Beitang Estuary of Tianjin,China was quantitatively studied. The bioturbation of test macrobenthos had obvious effects on the distribution of the sediment, and the effects differed with the macrobenthos. The disturbed intensity(diffusion coefficient, 10-3 cm²·d-1) of surface sediment under the effects of the macrobenthos was in order of N. diversicolor (2.95) >H. tientsinensis (1.00) >C. sinensis (0.78)>B. exarata. (0.35)>control (0.05), and that of deep sediment was H. tientsinensis (3.10)>N. diversicolor(2.33)>C. sinensis (0.28) > B. exarata (0.15) >control (0.05), which was mainly due to that the macrobenthos were belonged to different functional groups. There was a significant relationship between the bio-volume of test macrobentos and the diffusion coefficient of surface sediment (P<0.05), suggesting that the bio-volume of macrobenthos could be used as an indicator to predict their bioturbation capacity on esturaine sediment. [ABSTRACT FROM AUTHOR]