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CO2 flooding technology is an effective technical means to enhance the recovery of low permeability reservoirs. After CO2 comes into contact with crude oil， the asphaltene in the system is deposited in a solid form， which causes a certain blockage to the reservoir， but the dissolution improves the flow capacity of the reservoir as a whole at the same time. The damage of CO2 flooding to low permeability reservoirs under different injection methods is different. The organic scale plugging mechanism， reservoir wettability， and CO2-water solution corrosion evaluation experiments were carried out after continuous CO2 injection and CO2-water alternating injection. The variation characteristics of relative permeability curve parameters were evaluated， and the damage of different injection methods of CO2 flooding to low permeability reservoirs was quantitatively characterized. The results show that the organic scale produced by CO2 flooding would block the pore throat of the rock， but on the whole， the dissolution caused by the reaction of CO2 and chlorite is stronger， which makes the recovery of the low permeability reservoirs effectively enhanced. Moreover， the organic scale blockage caused by CO2-water alternating injection is weaker than that caused by continuous CO2 injection， and the dissolution effect is better. The permeability loss rate is lower. It could achieve a better oil displacement effect in pores with a radius of more than 0.2 μm and increase the pore space and flow channel of the rock so that the recovery of low permeability reservoir could be effectively improved.

Moso bamboo is excellent candidate for cadmium (Cd)/lead (Pb) phytoremediation, while rhizosphere microbiome has significant impact on phytoremediation efficiency of host plant. However, little is known about the rhizosphere bacterial communities of moso bamboo in Cd/Pb contaminated soils. Therefore, this study investigated the assembly patterns and key taxa of rhizosphere bacterial communities of moso bamboo in Cd/Pb polluted and unpolluted soils, by field sampling, chemical analysis, and 16S rRNA gene sequencing. The results indicated α-diversity between Cd/Pb polluted and unpolluted soils showed a similar pattern (p > 0.05), while β-diversity was significantly different (p < 0.05). The relative abundance analysis indicated α-proteobacteria (37%) and actinobacteria (31%) were dominant in Cd/Pb polluted soils, while γ-proteobacteria (40%) and α-proteobacteria (22%) were dominant in unpolluted soils. Co-occurrence network analysis indicated microbial networks were less complex and more negative in polluted soils than in unpolluted soils. Mantel analysis indicated soil available phosphorus, organic matter, and available Pb were the most important environmental factors affecting microbial community structure. Correlation analysis showed 11 bacterial genera were significantly positively related to Cd/Pb. Overall, this study identified the bacterial community composition of bamboo rhizosphere in responding to Cd/Pb contamination and provides a theoretical basis for microbe-assistant phytoremediation in the future. Novelty statement: To date, little is known about the bacterial communities in the rhizosphere of moso bamboo under Cd and Pb multiple stresses. This study investigated the assembly patterns and key taxa of rhizospheric bacterial communities of moso bamboo in Cd/Pb polluted and unpolluted soils. It was found that the bacterial community structure in bamboo rhizosphere is easily influenced by soil chemical environment, such as fertilities and heavy metals. The key bacterial taxa identified here could be target microbe in future microbe-assistant phytoremediation. [ABSTRACT FROM AUTHOR]

The intensive use of chemical fertilizers in China to maintain high crop yields has led to significant environmental degradation and destabilized crop production. Returning straw to soil presents a potential alternative to reduce chemical fertilizer requirements and enhance soil fertility. This study investigates the effects of different nitrogen (N) input levels and straw additions on crop phosphorus (P) uptake and soil P availability based on a long-term N-fertilizer trial. The treatments included no fertilizer input (CK), conventional (NPK), reduced NPK (0.75NPK), and straw-amended (SNPK) treatments. Results indicate that SNPK significantly enhances shoot P uptake and crop yields by 43.7–61.9% and 29.3–39.6%, respectively. The SNPK treatment improved rhizosphere P availability and increased the phosphorus activation coefficient (PAC) by 1.72-fold compared to NPK alone. The enhanced soil P availability under SNPK was primarily attributed to an abundance of functional microbes, leading to higher P storage in the microbial biomass P pool and its turnover. Additionally, SNPK promoted root exudate and phosphate-mobilizing microbes, enhancing P mobilization and uptake. Nitrogen fertilization primarily influenced root functional traits related to P acquisition. These findings provide valuable insights for developing effective fertilizer management strategies in maize–oilseed rape rotation systems, emphasizing the benefits of integrating straw with chemical fertilizers. [ABSTRACT FROM AUTHOR]

SUMMARY: The petals of rose (Rosa sp.) flowers determine the ornamental and industrial worth of this species. The number of petals in roses was previously shown to be subject to fluctuations in ambient temperature. However, the mechanisms by which rose detects and responds to temperature changes are not entirely understood. In this study, we identified short interstitial telomere motifs (telo boxes) in the second intron of AGAMOUS (RcAG) from China rose (Rosa chinensis) that play an essential role in precise temperature perception. The second intron of RcAG harbors two telo boxes that recruit telomere repeat binding factors (RcTRBs), which interact with CURLY LEAF (RcCLF) to compose a repressor complex. We show that this complex suppresses RcAG expression when plants are subjected to low temperatures via depositing H3K27me3 marks (trimethylation of lysine 27 on histone H3) over the RcAG gene body. This regulatory mechanism explains the low‐temperature‐dependent decrease in RcAG transcript levels, leading to the production of more petals under these conditions. Our results underscore an interesting intron‐mediated regulatory mechanism governing RcAG expression, enabling rose plants to perceive temperature cues and establish petal numbers. Significance Statement: Our research underscores a new intron‐mediated regulatory mechanism governing RcAG expression, enabling rose plants to perceive temperature cues and establish petal numbers. It might be of great interest to a broad range of readers including environmental response, epigenetic modification, floral organ development, and other researchers in related fields. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) miscible fracturing huff-and-puff technology now plays a pivotal role in enhancing crude oil recovery rates, particularly in reservoirs with challenging physical properties, strong water sensitivity, high injection pressure, and complex water-injection dynamics. In this study, the oil-increasing mechanism and huff-and-puff effect of CO2 miscible fracturing fluid are investigated through a comprehensive experimental approach. Specifically, experiments on PVT gas injection expansion, minimum miscible pressure, and CO2 miscible fracturing fluid huff and puff are conducted on the G fault block reservoir of the J Oilfield. The experimental findings demonstrate that injecting CO2 into reservoirs leads to an expansion in oil volume, a reduction in viscosity, and an increase in saturation pressure. Crude oil extraction is further enhanced by the addition of solubilizers and viscosity reducers. The use of solubilizers not only increases oil recovery rates but also reduces the minimum miscible pressure required for effective CO2 dispersion. We also found that shut-in times, permeability, and the huff-and-puff method used all have considerable impacts on huff-and-puff recovery rates. This study offers valuable technical insights, supporting the application of CO2 miscible fracturing huff-and-puff technology to enhance oil recovery rates in low-permeability reservoirs. [ABSTRACT FROM AUTHOR]

Rapid urbanization drives changes in suburban cropland and afforestation, but the impact on soil microbes and carbon (C) dynamics remains unclear. Using genetic sequencing (16S rRNA sequence and functional prediction), we assessed the effects of cropland intensification and afforestation on the soil microbial communities and C sequestration potential in a suburban agricultural area. Traditional rotation (rice–wheat) homogenized microbial diversity along soil depth (0–100 cm). Cropland intensification (rice–wheat to rice–vegetables) and afforestation (rice–wheat to forest) decreased fungal diversity below 20 cm, while bacterial diversity and dominant taxa were less affected, due to the advantages of bacterial diversity and dominant taxa distribution. Cropland intensification increased profile C accumulation, mainly due to excessive fertilization (obviously decreased aerobic_chemoheterotrophy below 20 cm in bacterial function), but not C stability (significantly increased permanganate oxidizable C (POXC), and microbial‐dependent C sources tend to from crop litter to soil sources). Afforestation offset C accumulation through no fertilization and inundation, but increased saprophytic function for C sequestration. In addition, pH and C had opposing effects on dominant microbial taxa, mitigating extreme differentiation. Subsoil was more sensitive to changes than topsoil. Altogether, soil C stability decoupled from C accumulation in the suburban agricultural area. Cropland intensification increased C accumulation yet decreased bacterial C sequestration potential and C stability; cropland afforestation facilitated fungi‐derived C accumulation and its C sequestration. Deep soil C sequestration was more vulnerable to suburban agriculture practices, emphasizing the need to consider subsoil C‐cycling in agricultural practices amid urbanization. [ABSTRACT FROM AUTHOR]

CO2 flooding technology is an effective technical means for tertiary oil recovery in high water cut reservoirs. Using an existing well pattern to inject CO2 is an economical and feasible development method under low contemporary oil prices. Although the particle migration caused during the displacement process will block the pore throat of the rock, the injection of CO2 can effectively reduce the CO2 injection pressure, and the dissolution that occurs during the injection process improves the seepage capacity of the fluid as a whole. In this study, assessments of particle migration and plugging after CO2 flooding and evaluations of rock dissolution by CO2-aqueous solution were carried out, and the variation characteristics of the relative permeability curve before and after displacement were evaluated, further explaining the influence of CO2 flooding on reservoir seepage capacity. The results show that, in the process of CO2 injection, the injection pressure decreases under different injection rates. After CO2 flooding under oil conditions, the core permeability loss was 43.8%, and after cleaning with toluene and anhydrous ethanol, the core permeability recovery was 24.3%, indicating that the particles were bound by crude oil during the migration process and accumulated into clusters, resulting in blockages. Although there was a certain degree of blockage, the CO2-aqueous solution mainly reacted with chlorite and released Ca2+, Mg2+, and Fe2+ ions. The concentration of Ca2+ increased by 157.43%, the concentration of Mg2+ decreased by 43.33%, and the concentration of Fe2+ decreased by 50.47%, indicating that, although the generated MgCO3 and Fe2O3 blocked the pore throat of the rock, the overall dissolution effect of CO2 on CaCO3 was stronger, and the overall seepage capacity of the fluid was improved. To a certain extent, this technique can improve the water injection capacity and the effect of subsequent water flooding. [ABSTRACT FROM AUTHOR]