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Pig farm biogas slurry is high in color and turbidity with high content of nitrogen and phosphorus. The use of microalgae-bacteria symbiosis can simultaneously and efficiently remove carbon，nitrogen and phosphorus，save energy and reduce consumption，and recover resources，meeting the needs of the new era for wastewater treatment. In this study，the three parameters of light intensity，aeration intensity and the proportion of microalgae and bacteria were optimized from the perspectives of pollutant removal and microbial growth. It was found that the amount of aeration had the greatest impact on nitrogen removal，while the three parameters had little impact on carbon and phosphorus removal. After weighted evaluation，the sequence of three factors followed aeration amount>light intensity>inoculation proportion，and the optimal parameter combination is light intensity at 550 μmol/（m2·s），aeration rate at 0.2 L/min，microalgae-bacteria inoculation ratio at 1∶1. The concentrations of TP，COD，TN and NH4+-N in the group with the best comprehensive score were 0.48，219.2，125.2，64 mg/L respectively，and the removal rates were 95.46%，88.58%，61.58% and 80.21% respectively. The particle size of microalgae-bacteria flocs in each group increased，and decreased with the increase of the microalgae-bacteria proportion.

Soil amelioration in coastal saline areas plays an important role in alleviating land resource shortages, improving regional ecological environments, ensuring food security, and promoting economic development. Plastic mulching (M) and the combination of freezing saline water irrigation and plastic mulching (WIM) are successful amelioration practices that dramatically reduce the salinity of surface soil and facilitate plant growth in coastal saline soil. However, the bacterial responses that are closely related to these amelioration practices in coastal saline soil remain poorly understood. In this study, bacterial richness and diversity, community composition, and potential ecological functions in the rhizosphere and bulk soils of cotton in M and WIM treatments, along with a control treatment, were investigated using high-throughput sequencing in a coastal saline field. The results showed that both the M and WIM treatments increased bacterial richness and alpha diversity, which were in general significantly higher in bulk soil than in rhizosphere soil. Non-metric multidimensional scaling and the Bray–Curtis dissimilarity analysis revealed that the bacterial community in rhizosphere soil was assembled far from those in the control and bulk soils and behaved more specifically in rhizosphere soil than in bulk soil. The relative abundances of most of the dominant phyla showed opposite trends of variation in bulk and rhizosphere soils compared to those in control soil in both M and WIM treatments; in particular, the specific bacterial groups of Proteobacteria and Actinobacteria decreased in bulk soil but significantly increased in rhizosphere soil. Functional groups of chemoheterotrophy, aerobic chemoheterotrophy, and nitrate reduction were predominant in rhizosphere rather than bulk soil, according to the Functional Annotation of Prokaryotic Taxa. These findings improve the understanding of the mechanism of bacterial responses to amelioration practices M and WIM in coastal saline soils and provide valuable information for the development of amelioration techniques based on agricultural practices and soil microbiome to enhance plants' adaptability to saline soil in the future. [ABSTRACT FROM AUTHOR]

By functionalizing organic ligands and regulating metal nodes, metal–organic frameworks (MOFs) exhibit a variety of catalytic properties, which not only expand their application in biomass conversion but also increase the designability of catalysts. Herein, we have developed a synthesis strategy to fabricate multicomponent nanocatalysts (M–ZrO2/N–C, M = Ni, Fe, Co, Cu) derived from postsynthetic modification of zirconium–organic frameworks using Schiff base as an effective bridge. These nanocatalysts were utilized for the hydrogenation of bio-derived methyl levulinate to γ-valerolactone. The catalytic performance demonstrates that Ni–ZrO2/N–C possesses superior catalytic activity (99.9% conversion of methyl levulinate and 94.7% selectivity of γ-valerolactone), which could be attributed to the synergy effect of metal Ni and ZrO2 species. Various characterization methods (X-ray photoelectron spectroscopy (XPS) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS)) indicated that metallic nickel activated H2, and the introduction of ZrO2 provided sufficient Lewis acid sites, accelerating the intramolecular esterification process. [ABSTRACT FROM AUTHOR]